The Journal of Thoracic and Cardiovascular Surgery - Articles in Press

Cardiac dysfunction induced by experimental myocardial infarction impairs the host defense response to bacterial infection in mice because of reduced phagocytosis of Kupffer cells - Corrected Proof

2010-02-08

Objective: This study was undertaken to investigate the effects of cardiac dysfunction induced by experimental myocardial infarction on the host defense response to bacterial infection and the role of Kupffer cells in mediating this response.Methods: Myocardial infarction was induced in C57BL/6 mice by ligation of the left anterior descending coronary artery. Mice were challenged with Escherichia coli intravenously 1, 5, and 14 days after myocardial infarction or sham operation. Thereafter, the cytokine production and the function of their Kupffer cells were assessed.Results: Mice with myocardial infarction showed remarkable cardiac dysfunction and had a significantly lower survival than sham mice after bacterial challenge at 5 days after surgery; bacterial challenge at 1 or 14 days after surgery resulted in no difference in survival between myocardial infarction and sham mice. The phagocytic activity of Kupffer cells, assessed by fluorescein isothiocyanate microspheres, remarkably decreased in mice with myocardial infarction 5 days after surgery. Serum peaks of tumor necrosis factor and interferon-γ after bacterial challenge were also suppressed in mice with myocardial infarction at 5 days. Production of these cytokines and immunoglobulin-M from liver mononuclear cells was also impaired in mice with myocardial infarction. Enhancement of the phagocytic activity of Kupffer cells by C-reactive protein significantly improved survival after infection in mice with myocardial infarction, although neither interleukin-18 nor immunoglobulin-M treatment improved survival.Conclusion: Cardiac dysfunction induced by myocardial infarction renders mice susceptible to bacterial infection and increases mortality because of a reduced ability of Kupffer cells to clear infectious bacteria. C-reactive protein-enhanced phagocytic activity of Kupffer cells may improve the poor prognosis after bacterial infection in mice with myocardial infarction.

The effect of transplant center volume on survival after heart transplantation: A multicenter study - Corrected Proof

Jeffrey H. Shuhaiber, Jeff Moore, David B. Dyke — 2010-02-08

Objective: Few studies have examined the association between procedural volume and clinical outcomes in heart transplantation. This retrospective study was performed on a contemporary cohort of heart transplant recipients to better elucidate the effect of transplant center volume on 1-year mortality.Methods: Data from the Scientific Registry of Transplant Recipients were used to analyze the relationship between transplant center volume and short-term survival. Center volume designation (very low, low, medium, and high) was assigned on the basis of quartiles with approximately equal numbers of patients per group. Survival differences were explored using Cox proportional hazards modeling to adjust for differences in variables between volume groups and to determine variables associated with 1-year mortality.Results: Between January 1, 1999, and May 31, 2005, 13,230 heart transplantations were performed at 147 transplant centers in the United States. Although most recipient and donor characteristics were similar across quartiles, larger volume centers were more likely to perform transplantations in older candidates and accept organs from older donors with longer cold ischemia times. A statistically significant relationship between transplant center volume and 1-year mortality was observed. Compared with the reference group (very low volume), the hazard ratios for the low, medium, and high-volume quartiles were 0.71, 0.64, and 0.56, respectively (P < .001 for each group compared with the reference).Conclusion: There was a significant association between transplant center volume and 1-year survival. Patients who undergo cardiac transplantation at very low-volume centers are at higher risk for early mortality than those who undergo transplantation in higher-volume centers.

The relationship of plasma transfusion from female and male donors with outcome after cardiac surgery - Corrected Proof

2010-02-08

Objective: Pulmonary dysfunction is common in transfused patients recovering from heart surgery. Plasma transfusion from female donors has been linked with rare catastrophic lung injury, but its relationship with outcome after cardiac surgery is poorly understood. We examined whether plasma donor gender is related to postcardiac surgery pulmonary dysfunction and death or prolonged hospitalization.Methods: In this retrospective case-control study, cardiac surgery candidates who received plasma perioperatively from only female donors were compared with male-only recipients who were matched for the number of units transfused and surgery date.Results: In a dataset of 2157 recipients, there were no blood bank–reported complications, but escalating plasma transfusion was associated with increased 30-day mortality (odds ratio, 1.52 per unit; P = .0001). From the 1069 recipients receiving plasma exclusively from female or male donors, 390 matched pairs were identified. Recipients of female compared with male donor plasma had a lower incidence of pulmonary dysfunction (5.9% vs 10.8%; P = .01) and death or hospitalization more than 10 days (9% vs 16.4%; P = .002) but similar long-term survivals.Conclusion: Escalating plasma transfusion was associated with 30-day mortality, but female donor plasma recipients had less pulmonary dysfunction and fewer poor outcomes compared with male-only recipients. Although our retrospective study findings neither support nor refute a strategic policy to exclude female donor plasma to reduce catastrophic transfusion-related acute lung injury, they raise concern that such a policy may have unanticipated effects on outcome in patients undergoing cardiac surgery and highlight a need for additional studies in this and other patient groups.

Normokalemic adenosine–lidocaine cardioplegia: Importance of maintaining a polarized myocardium for optimal arrest and reanimation - Corrected Proof

Kathryn L. Sloots, Geoffrey P. Dobson — 2010-02-04

Objective: Depolarizing potassium cardioplegia does not afford optimal cardioprotection in pediatric or adult patients requiring complicated operative procedures. Polarizing adenosine–lidocaine cardioplegia has been shown to be cardioprotective without hyperkalemia. Our aim was to examine the effects of changing extracellular potassium levels in adenosine–lidocaine cardioplegia on arrest and reanimation properties.Methods: Isolated–perfused rat hearts (n = 96) were arrested at 32°C to 33°C for 1 or 2 hours with intermittent 200 μmol/L adenosine and 500 μmol/L lidocaine in modified Krebs–Henseleit buffer with 0.1, 3.0, 5.9, 10, and 16 mmol/L potassium or with 16 or 25 mmol/L potassium in Krebs–Henseleit buffer (n = 8 for each group). Membrane potentials were estimated in the arrested ventricular myocardium (n = 42), and recovery function was measured in working mode during 60 minutes' reperfusion.Results: Arrest was interrupted by breakout beats in the adenosine–lidocaine hypokalemic (0.1 and 3 mmol/L potassium) and non–adenosine–lidocaine hyperkalemic (16 and 25 mmol/L potassium) groups. The membrane potentials for the non–adenosine–lidocaine 16 and 25 mmol/L potassium groups were −51 and −39 mV, and those for the adenosine–lidocaine groups (0.1, 3.0, 5.9, 10, and 16 mmol/L potassium) were −183, −94, −75, −65, and −49 mV, respectively. After 1 hour of arrest, coronary vascular resistance increased linearly in adenosine–lidocaine cardioplegia with increasing potassium levels (5.9, 10, and 16 mmol/L), and the slope increased more than 2-fold after 2 hours. Nearly 40% of hearts in the adenosine–lidocaine (0.1 mmol/L potassium) and non–adenosine–lidocaine 25 mmol/L potassium groups failed to recover after 1 hour arrest. After 2 hours, hearts in the polarizing (5.9 mmol/L potassium) adenosine–lidocaine group increased coronary vascular resistance by only 30% and spontaneously recovered 107% heart rate, 92% systolic pressure, 81% aortic flow, and 113% coronary flow (all metrics returned 85% to 100% at 15 minutes) with no reperfusion arrhythmias. In contrast, hearts in the adenosine–lidocaine (3, 10, and 16 mmol/L potassium) groups were all slow to recover (15% to 40% return at 15 minutes) and experienced arrhythmias. Increasing potassium levels in adenosine–lidocaine cardioplegia from 5.9 to 16 mmol/L resulted in a 67% loss of left ventricular contractility.Conclusions: Polarizing adenosine–lidocaine cardioplegia (5.9 mmol/L potassium) administered intermittently at 33°C provides superior arrest and reanimation profiles under normokalemic conditions when the myocardial cell membrane potential is close to its resting state.

Right ventricular failure in patients with the HeartMate II continuous-flow left ventricular assist device: Incidence, risk factors, and effect on outcomes - Corrected Proof

2010-02-04

Objective: The aim of this study was to evaluate the incidence, risk factors, and effect on outcomes of right ventricular failure in a large population of patients implanted with continuous-flow left ventricular assist devices.Methods: Patients (n = 484) enrolled in the HeartMate II left ventricular assist device (Thoratec, Pleasanton, Calif) bridge-to-transplantation clinical trial were examined for the occurrence of right ventricular failure. Right ventricular failure was defined as requiring a right ventricular assist device, 14 or more days of inotropic support after implantation, and/or inotropic support starting more than 14 days after implantation. Demographics, along with clinical, laboratory, and hemodynamic data, were compared between patients with and without right ventricular failure, and risk factors were identified.Results: Overall, 30 (6%) patients receiving left ventricular assist devices required a right ventricular assist device, 35 (7%) required extended inotropes, and 33 (7%) required late inotropes. A significantly greater percentage of patients without right ventricular failure survived to transplantation, recovery, or ongoing device support at 180 days compared with patients with right ventricular failure (89% vs 71%, P < .001). Multivariate analysis revealed that a central venous pressure/pulmonary capillary wedge pressure ratio of greater than 0.63 (odds ratio, 2.3; 95% confidence interval, 1.2–4.3; P = .009), need for preoperative ventilator support (odds ratio, 5.5; 95% confidence interval, 2.3–13.2; P < .001), and blood urea nitrogen level of greater than 39 mg/dL (odds ratio, 2.1; 95% confidence interval, 1.1–4.1; P = .02) were independent predictors of right ventricular failure after left ventricular assist device implantation.Conclusions: The incidence of right ventricular failure in patients with a HeartMate II ventricular assist device is comparable or less than that of patients with pulsatile-flow devices. Its occurrence is associated with worse outcomes than seen in patients without right ventricular failure. Patients at risk for right ventricular failure might benefit from preoperative optimization of right heart function or planned biventricular support.

Risk factor analysis for postoperative acute respiratory distress syndrome and early mortality after pneumonectomy: The predictive value of preoperative lung perfusion distribution - Corrected Proof

Joon Bum Kim, Sei Won Lee, Seung-Il Park, Yong Hee Kim, Dong Kwan Kim — 2010-02-04

Objectives: This study aims to establish the preoperative risk factors in the development of acute respiratory distress syndrome (ARDS) and early mortality after pneumonectomy for lung cancer and to examine the influence of reduced pulmonary perfusion on outcomes.Methods: Between 1994 and 2009, of 425 patients who underwent simple pneumonectomy for primary lung cancer, 164 who were preoperatively evaluated with lung perfusion scanning formed the population of this study.Results: Of 30 (18.3%) patients who had major pulmonary complications, 17 (10.4%) progressed to ARDS, 15 of whom subsequently died. On multivariable logistic regression analyses, lower predicted postoperative forced expiratory volume in 1 second (ppo-FEV1; relative risk of 0.93 [P = .020] for ARDS and 0.94 [P = .027] for mortality) and greater perfusion fraction of resected lung (relative risk of 1.10 [P = .003] for ARDS and 1.09 [P = .002] for mortality) were found to be independent factors associated with ARDS and early mortality. With a cut-off value of 35% for perfusion fraction of resected lung, patients with a perfusion fraction of greater than 35% had a greater incidence of ARDS (17.3% vs 3.3%, P = .005) and early mortality (19.8% vs 6.0%, P = .010) than those with a perfusion fraction of 35% or less.Conclusions: Patients with a low ppo-FEV1, a high perfusion fraction of resected lung, or both had a higher incidence of ARDS and early mortality after pneumonectomy. Therefore, although the ppo-FEV1 appears to be within an acceptable limit for pneumonectomy, much attention should be given to patients with a high perfusion fraction of resected lung.

Effect of pressure management during hypothermic selective cerebral perfusion on cerebral hemodynamics and metabolism in pigs - Corrected Proof

2010-02-01

Objective: The effect of perfusion pressure on cerebral hemodynamics and metabolism during selective cerebral perfusion in patients undergoing aortic surgery is still unknown. This study explored cerebral blood flow, metabolic rate, and intracranial pressure at different pressure rates.Methods: Twenty-five pigs (32–38 kg) were cooled during cardiopulmonary bypass to 25°C. After 10 minutes of hypothermic circulatory arrest, the animals were randomized to 60 minutes of selective cerebral perfusion at 3 different perfusion pressures: group I (n = 8), 40 mm Hg; group II (n = 9), 60 mm Hg; and group III (n = 8), 80 mm Hg. Microspheres were injected at baseline, the coolest temperature, and 5, 15, 25, and 60 minutes of selective cerebral perfusion, respectively, to calculate cerebral hemodynamics.Results: Cerebral blood flow decreased during cooling to 54% of baseline value (50 mL/min per 100 g) and recovered in all groups during the first 15 minutes of selective cerebral perfusion. In groups I and II it reached 110% to 113% of baseline values, whereas group III animals showed significantly higher values (P25min = .003) during the first 25 minutes of selective cerebral perfusion (360%; 153 mL/min per 100 g). Cerebral blood flow decreased in all groups over the following 35 minutes of selective cerebral perfusion to 57% of baseline value. Cooling to 25°C decreased the intracranial pressure to 10 mm Hg (93%). During selective cerebral perfusion, groups I and II showed a further intracranial pressure decrease to 45% and 82%, respectively, whereas group III, with 15 mm Hg (128%), had significantly higher intracranial pressure values at the end of selective cerebral perfusion (P25min = .03 and P60min = .02). The metabolic rate decreased to 30% of the baseline value during cooling, reaching 34% to 38% after 60 minutes of selective cerebral perfusion, with no significant differences between groups.Conclusion: High-pressure perfusion provides no benefit during long-term selective cerebral perfusion at 25°C. Higher cerebral blood flow during the initial 25 minutes of selective cerebral perfusion leads to cerebral edema, with no alteration in metabolic rate.

Efficacy of a novel bipolar radiofrequency ablation device on the beating heart for atrial fibrillation ablation: A long-term porcine study - Corrected Proof

2010-02-01

Objective: Over recent years, a variety of energy sources have been used to replace the traditional incisions of the Cox maze procedure for the surgical treatment of atrial fibrillation. This study evaluated the safety and efficacy of a new bipolar radiofrequency ablation device for atrial ablation in a long-term porcine model.Methods: Six pigs underwent a Cox maze IV procedure on a beating heart off cardiopulmonary bypass using the AtriCure Isolator II bipolar ablation device (AtriCure, Inc, Cincinnati, Ohio). In addition, 6 pigs underwent median sternotomy and pericardiotomy alone to serve as a control group. All animals were allowed to survive for 30 days. Each pig underwent induction of atrial fibrillation and was then humanely killed to remove the heart en bloc for histologic assessment. Magnetic resonance imaging scans were also obtained preoperatively and postoperatively to assess atrial and ventricular function, pulmonary vein anatomy, valve function, and coronary artery patency.Results: All animals survived the operation. Electrical isolation of the left atrial appendage and the pulmonary veins was documented by pacing acutely and at 30 days in all animals. No animal that underwent the Cox maze IV procedure was able to be induced into atrial fibrillation at 30 days postoperatively, compared with all the sham animals. All 257 ablations examined were discrete, linear, and transmural, with a mean lesion width of 2.2 ± 1.1 mm and a mean lesion depth of 5.3 ± 3.0 mm.Conclusions: The AtriCure Isolator II device was able to create reliable long-term transmural lesions of the modified Cox maze procedure on a beating heart without cardiopulmonary bypass 100% of the time. There were no discernible effects on ventricular or valvular function.

Intermittent regurgitation caused by incomplete leaflet closure of the Medtronic ADVANTAGE bileaflet heart valve: Analysis of the underlying mechanism - Corrected Proof

2010-02-01

Objective: Clinical echocardiographic assessments of the Medtronic ADVANTAGE (Medtronic Inc, Minneapolis, Minn) prosthesis in the aortic position revealed a phenomenon identified as “intermittent regurgitation.” An in vitro investigation was initiated to identify the underlying mechanism.Methods: In a pulse duplicator environment, 6 ADVANTAGE size 23 aortic valves were analyzed. Leaflet motion and flow through the valves were documented using echocardiography with color Doppler flow, digital high speed imaging, and flow meter assessment.Results: Intermittent regurgitation could be reproduced in all 6 of the tested valves within limited ranges of flow, pressure, and valve orientation. By virtue of high-speed imaging, the mechanism underlying intermittent regurgitation was identified. During intermittent regurgitation, the leading edge of the second-to-close leaflet makes contact with the chamfer on the leading edge of the first-to-close leaflet. The fluid closing forces working on the first-to-close leaflet prevent it from shifting back so that the leading edge of the second-to-close leaflet remains positioned against the chamfer of the first-to-close leaflet. In this position, the major radius of the second-to-close leaflet does not reach the housing's major radius. Therefore, a crescent-shaped gap remains between the leaflet tip of the second-to-close leaflet and the housing major radius during all or part of diastole. The regurgitant fraction can increase from a normal range of 6% to 25% during an intermittent regurgitation beat.Conclusion: In vitro intermittent regurgitation can be induced in the size 23 aortic ADVANTAGE valve under a limited range of conditions. To avoid possible misinterpretations, the phenomenon must be known in detail by all physicians dealing with patients with an ADVANTAGE valve.

Functional mitral stenosis after surgical annuloplasty for ischemic mitral regurgitation: Importance of subvalvular tethering in the mechanism and dynamic deterioration during exertion - Corrected Proof

2010-02-01

Objective: Diastolic subvalvular mitral leaflet tethering by left ventricular remodeling that restricts leaflet opening in the presence of annular size reduction by surgery for ischemic mitral regurgitation potentially causes functional mitral stenosis in the absence of organic leaflet lesions. Exercise, known to worsen systolic tethering and ischemic mitral regurgitation, might also dynamically exacerbate such mitral stenosis by increasing tethering. This study evaluates the mechanism and response of such mitral stenosis to exercise.Methods: We measured the diastolic mitral valve area, annular area, and peak and mean transmitral pressure gradient by echocardiography in 20 healthy individuals and 31 patients who underwent surgical annuloplasty for ischemic mitral regurgitation.Results: Although the mitral valve area and annular area did not significantly differ in healthy individuals (4.7 ± 0.6 cm2 vs 5.2 ± 0.6 cm2, not significant), mitral valve area was significantly smaller than the annular area in patients after annuloplasty (1.6 ± 0.2 cm2 vs 3.3 ± 0.5 cm2, P < .01). The mitral valve area was less than 1.5 cm2 only after the surgery (P < .01) and was significantly correlated with restricted leaflet opening (r2 = 0.74, P < .001), left ventricular dilatation (r2 = 0.17, P < .05), and New York Heart Association functional class (P < .05). Exercise stress echocardiography of 12 patients demonstrated dynamic worsening in functional mitral stenosis (mitral valve area: 2.0 ± 0.5 cm2 to 1.4 ± 0.2 cm2, P < .01; mean pressure gradient: 1.5 ± 0.9 mm Hg to 6.0 ± 2.2 mm Hg, P < .01).Conclusion: Persistent subvalvular leaflet tethering in the presence of annular size reduction by surgery in ischemic mitral regurgitation frequently causes functional mitral stenosis at the leaflet tip level, which is related to heart failure symptoms and can be dynamic with significant exercise-induced worsening.

Thoracoscopic pulmonary vein isolation in patients with atrial fibrillation and failed percutaneous ablation - Corrected Proof

2010-02-01

Objective: Pulmonary vein isolation is indicated in patients with symptomatic isolated atrial fibrillation not controlled with antiarrhythmic therapy. We describe our surgical experience with thoracoscopic pulmonary vein isolation in patients in whom percutaneous ablation has failed.Methods: Thirty-four adult patients with unsuccessful catheter ablations (range 1–4, mean 2 ± 1) underwent thoracoscopic bipolar-radiofrequency pulmonary vein isolation. Seventeen patients had paroxysmal atrial fibrillation, 12 with persistent and 5 with long-standing persistent fibrillation, for a mean of 6 years (range 3–10 years), 13 years (5–25 years), and 9 years (3–15 years), respectively.Results: There was no mortality during the procedure or follow-up (mean 16 ± 11 months). Two patients needed conversion to thoracotomy owing to hemorrhage, and ablation could not be completed. Antiarrhythmic therapy was withdrawn 3 months postoperatively. Postoperative sinus rhythm was maintained in 82% of those with paroxysmal atrial fibrillation (13/15 at 6 months, 9/11 at 12 months), 60% had persistent atrial fibrillation (8/12 at 6 months and 6/10 at 12 months), and 20% had long-standing persistent atrial fibrillation (1/5 at 6 and 12 months). Preoperative left atrial diameter significantly differed between patients with paroxysmal fibrillation (mean 42 ± 6 mm) and those with persistent and long-standing persistent fibrillation (means 50 ± 4 and 47 ± 2 mm). Left atrial size greater than 45 mm and atrial fibrillation type were preoperative factors that significantly influenced outcome in the univariate logistic regression analysis.Conclusions: Thoracoscopic pulmonary vein isolation in patients with previously unsuccessful catheter ablations demonstrates satisfactory sinus rhythm maintenance rates in paroxysmal and persistent atrial fibrillation, but not in long-standing persistent atrial fibrillation. As with other minimally invasive surgical techniques, there is an important learning curve.

Explantation of a 44-year-old Starr–Edwards mitral valve for delayed hemolysis - Corrected Proof

Joss Fernandez, Robert Saeid Farivar — 2010-02-01

A 68-year-old woman was admitted 44 years after undergoing mitral valve replacement with a Starr–Edwards (SE) prosthesis (Edwards Lifesciences, Irvine, Calif) for rheumatic mitral valve stenosis. Since implantation of the prosthesis in 1965 via thoracotomy, the patient had done well and maintained her anticoagulation with warfarin sodium (Coumadin). She now had fatigue and anemia. Of note, 2 years earlier the patient had had third-degree heart block necessitating the implantation of a dual-chamber pacemaker. A full workup including upper and lower endoscopy did not reveal a source of bleeding. Hematologic testing showed decreased haptoglobin, a high lactic dehydrogenase value, and increased reticulocyte count, consistent with a hemolytic anemia. Bone marrow biopsy was performed, which showed erythroid hyperplasia, normocellular bone marrow, normal megakaryocytes, and absent iron, indicative of iron deficiency anemia. Despite iron replacement therapy she continued to become increasingly transfusion dependent. She received 9 units of blood in 1 month alone. Echocardiogram revealed normal prosthetic mitral valve function with a mitral valve mean gradient of 6 mm Hg, a severely calcified aortic valve with an aortic valve mean gradient of 58 mm Hg, and an aortic valve area of less than 1.0 cm2.

Secure closure of the tracheal incision after natural orifice transluminal endoscopic surgery with a silicone tracheal stent - Corrected Proof

Yun-Hen Liu, Yi-Chen Wu, Tzu-Ping Chen, Po-Jen Ko — 2010-02-01

Since its introduction in 2004, natural orifice transluminal endoscopic surgery (NOTES) has attracted the interest of many clinicians and researchers and demonstrated technical feasibility and efficacy when used in various types of intra-abdominal operations, including transgastric liver biopsy, cholecystectomy, tubal ligation, and peritoneoscopy.

Hybrid procedure as an alternative to surgical palliation of high-risk infants with hypoplastic left heart syndrome and its variants - Corrected Proof

2010-02-01

Objectives: Despite improvements in the surgical management of neonates with the hypoplastic left heart syndrome and its variants, there is a subset of children who have a high predicted mortality. We have analyzed and report our results with the hybrid approach in the management of these high-risk patients.Methods: Children identified by our selection criteria underwent the initial hybrid procedure performed in the catheterization laboratory. This consists of surgical banding of the branch pulmonary arteries and stenting of the arterial duct. This was followed 3 to 6 months later by the combined stage I and II Norwood operation or biventricular repair.Results: Between December 2005 and May 2008, 21 neonates were selected for the hybrid procedure, of whom 16 had typical hypoplastic left heart syndrome. The remaining 5 neonates had severe aortic stenosis with borderline left ventricular dimensions or poor left ventricular function at presentation. Four neonates had a virtually intact interatrial septum and required urgent intervention immediately after birth. There were 6 deaths as inpatients or up to 30 days after the procedure and 1 interstage death before the combined stage I and II operation. Thus far, of 12 babies who have undergone the next operation, 9 have had the combined stage I and II operation and 3 have had a biventricular repair. Two of these 12 babies have died after the combined stage I and II operation.Conclusion: A hybrid approach may be a valuable alternative to the management of high-risk neonates with hypoplastic left heart syndrome and its variants.

Noninvasive estimation of left ventricular filling pressures in patients with heart failure after surgical ventricular restoration and restrictive mitral annuloplasty - Corrected Proof

2010-02-01

Objective: Doppler echocardiography, including tissue Doppler imaging, is widely applied to assess diastolic left ventricular function using early transmitral flow velocity combined with mitral annular velocity as a noninvasive estimate of left ventricular filling pressures. However, the accuracy of early transmitral flow velocity/mitral annular velocity in patients with heart failure, particularly after extensive cardiac surgery, is debated. Global diastolic strain rate during isovolumic relaxation obtained with 2-dimensional speckle-tracking analysis was recently proposed as an alternative approach to estimate left ventricular filling pressures.Methods: We analyzed diastolic function in patients with heart failure after surgical ventricular restoration and/or restrictive mitral annuloplasty. Echocardiography, including tissue Doppler imaging and speckle-tracking analysis, was performed to determine early transmitral flow velocity/atrial transmitral flow velocity, isovolumetric relaxation time, deceleration time, early transmitral flow velocity/mean mitral annular velocity, strain rate during isovolumic relaxation, and early transmitral flow velocity/strain rate during isovolumic relaxation. These noninvasive indices were correlated with relaxation time constant Tau, peak rate of pressure decline, and left ventricular end-diastolic pressure obtained in the catheterization room using high-fidelity pressure catheters.Results: Twenty-three patients were analyzed 6 months after restrictive mitral annuloplasty (n = 8), surgical ventricular restoration (n = 4), or a combined procedure (n = 11). The strongest correlation with invasive indices, in particular left ventricular end-diastolic pressure, was found for strain rate during isovolumic relaxation (r = −0.76, P < .001). Early transmitral flow velocity/mean mitral annular velocity did not correlate significantly with any of the invasive indices. Strain rate during isovolumic relaxation (cutoff value < 0.38 s−1) accurately predicted left ventricular end-diastolic pressure of 16 mm Hg or more with 100% sensitivity and 93% specificity.Conclusion: In a group of patients with heart failure who were investigated 6 months after cardiac surgery, early transmitral flow velocity/mean mitral annular velocity correlated poorly with invasively obtained diastolic indexes. Global strain rate during isovolumic relaxation, however, correlated well with left ventricular end-diastolic pressure and peak rate of pressure decline. Our data suggest that global strain rate during isovolumic relaxation is a promising noninvasive index to assess left ventricular filling pressures in patients with heart failure after extensive cardiac surgery, including restrictive mitral annuloplasty and surgical ventricular restoration.

Technical considerations to avoid pitfalls during transapical aortic valve implantation - Corrected Proof

2010-02-01

Objective: Transapical aortic valve implantation is a recent therapeutic advance for aortic valvular disease. We sought to identify complications—and the relevant technical and management considerations—from our learning curve with this procedure.Methods: We retrospectively reviewed perioperative complications during the first 60 transapical aortic valve implantations at a single institution, performed under compassionate release for patients who were candidates neither for conventional aortic valve replacement nor for transfemoral aortic valve implantation. Access was through a small left anterolateral thoracotomy. Particular attention was paid to securing the apical access site. Rapid ventricular pacing to reduce cardiac forward flow was used during balloon valvuloplasty and valve deployment. Careful positioning was guided by echocardiography and fluoroscopy.Results: This was a select, high-risk (mean Society of Thoracic Surgeons score, 12.3% ± 7.8% mortality) cohort. Mean age was 81.1 ± 7.8 years. Technical success was achieved in 59 (98.3%) cases. One valve was malpositioned too far toward the ventricle, necessitating that a second device be implanted within it. In-hospital, 30-day mortality was 18.3% (11 deaths) overall, decreasing from 33.3% in the first 15 patients to 13.3% in the subsequent 45 patients. The only intraoperative death probably resulted from left main ostial obstruction by extensively calcified aortic cusps. Significant left ventricular apical bleeding occurred in 3 (5.0%) patients. Other complications included stroke in 2 (3.3%) patients and permanent atrioventricular block in 3 (5.0%). There were 4 (6.6%) cases of late pseudoaneurysm of the left ventricular apical access site.Conclusions: Important lessons have been learned from our early experience with transapical aortic valve implantation, and these may guide others as this technology is adopted more broadly.

A formidable task: Population analysis predicts a deficit of 2000 cardiothoracic surgeons by 2030 - Corrected Proof

Thomas E. Williams, Benjamin Sun, Patrick Ross, Andrew M. Thomas — 2010-02-01

Objective: To estimate the cardiovascular workforce needed by 2030 to meet the needs of our population and to quantify its costs. Our field is changing. The volume of surgery and the nature of the surgery are changing. The nation's population grew from 227,000,000 to 282,000,000 between 1980 and 2000, and by 2030 the population is estimated to be 364,000,000. At the same time, the applications for fellowship in our specialty are decreasing at an alarming rate. The American Board of Thoracic Surgery has certified 4500 cardiothoracic surgeons since 1975, but only 1300 in the last 10 years. The US Department of Health and Human Services predicts only 3620 full-time cardiothoracic surgeons in 2020. Will we have enough cardiovascular and thoracic surgeons?Methods: Retrospective examination of the pertinent literature and with a modified Richard Cooper's economic trend analysis, a population algorithm with a ratio of physicians to population of 1.42 per 100,000. Each thoracic surgeon is predicted to practice 30 years from Board certification to retirement. The Balanced Budget Act will not be revised; therefore, we will certify 100 graduates from our programs per year. The assumed salaries will be $50,000 with benefits of 30% and $15,000 of additional Direct Medical Education costs.Results: The population in 2030 will be 364,000,000 with 5169 cardiothoracic surgeons needed at that time. Unfortunately, there will be approximately only 3200 cardiothoracic surgeons in practice with a shortage of approximately 2000. To maintain our current status per 100,000 population from 2011 to 2030, we will have to train 4000 residents. The total person years would be approximately 28,000. The cost for this is more than $2,000,000,000. The annual cost for this training prorated over 20 years would be more than $110,000,000.Conclusion: We must train approximately 4000 surgeons, an extra 100 per year, in our specialty to meet the needs of the population by 2030. That will cost approximately $2,250,000,000. To do this, the Balanced Budget Act of 1997 must be revised to permit more residents to be trained in the United States.

Effects of partial thrombosis on distal aorta after repair of acute DeBakey type I aortic dissection - Corrected Proof

2010-02-01

Objective: Prognostic implications of partial thrombosis of the residual aorta after repair of acute DeBakey type I aortic dissection have not been elucidated. We sought to analyze the impact of partial thrombosis on segmental growth rates, distal aortic reprocedures, and long-term survival.Methods: A total of 118 consecutive patients (55% were male; mean age, 60 years) with acute DeBakey type I aortic dissection underwent surgical repair (1997–2007). The hospital mortality rate was 17.8%. Survivors underwent serial computed tomography scans. Segment-specific average rates of enlargement were analyzed. Distal reprocedures and patient survival were examined.Results: Sixty-six patients had imaging data sufficient for growth rate calculations. The median diameters within 2 weeks after repair were as follows: aortic arch, 3.5 cm; descending aorta, 3.6 cm; and abdominal aorta, 2.4 cm. Subsequent growth rates were artic arch, 0.34 mm/y, descending aorta, 0.51 mm/y, and abdominal aorta, 0.35 mm/y. Partial thrombosis of the residual aorta predicted greater growth in the distal aorta (P = .005). There were 13 distal aortic reprocedures (5 reoperations, 8 stent graft insertions) for 10 years, and reprocedure-free survival was 66%. Partial thrombosis (P = .002) predicted greater risk of aorta-related reprocedures. Cox analysis revealed that estimated glomerular filtration rate less than 60 mL/min/1.73 m2 (P = .030), reintubation (P = .002), and partial thrombosis (P = .023) were independent predictors for poor survival.Conclusion: Partial thrombosis of the false lumen after repair of acute DeBakey type I aortic dissection, compared with complete patency or complete thrombosis, is a significant independent predictor of aortic enlargement, aorta-related reprocedures, and poor long-term survival.

Discussion - Corrected Proof

2010-02-01

Dr Anthony Estrera (Houston, Tex). I have nothing to disclose. As referenced by Dr Song, a recent evaluation of the IRAD experience demonstrated the potentially detrimental effect of the partially thrombosed false lumen in aortic dissection. This study by Song and colleagues analyzed this effect in relation to post-repair of acute type I aortic dissection. The strength of this study is not in the early results but rather the late follow-up. Song and colleagues determined, in addition to decreased late survival, greater aortic growth, and more frequent aortic reinterventions were observed in those patients with a partially thrombosed false lumen, giving us some potential causes for this increased late mortality.

Discussion - Corrected Proof

2010-02-01

Dr Irving Kron (Charlottesville, Va). The authors make the case that there will be a predicted shortage of surgeons in the United States by the year 2030. The American Association for Thoracic Surgeons and the Society of Thoracic Surgeons in association with the Association of American Medical Colleges developed an article that is now in press in Circulation that pretty much comes up with the same conclusion, about a 25% shortage of CT surgeons by 2025.

How much of the intraaortic balloon volume is displaced toward the coronary circulation? - Corrected Proof

Christina Kolyva, George M. Pantalos, John R. Pepper, Ashraf W. Khir — 2010-01-18

Objective: During intraaortic balloon inflation, blood volume is displaced toward the heart (Vtip), traveling retrograde in the descending aorta, passing by the arch vessels, reaching the aortic root (Vroot), and eventually perfusing the coronary circulation (Vcor). Vcor leads to coronary flow augmentation, one of the main benefits of the intraaortic balloon pump. The aim of this study was to assess Vroot and Vcor in vivo and in vitro, respectively.Methods: During intraaortic balloon inflation, Vroot was obtained by integrating over time the aortic root flow signals measured in 10 patients with intraaortic balloon assistance frequencies of 1:1 and 1:2. In a mock circulation system, flow measurements were recorded simultaneously upstream of the intraaortic balloon tip and at each of the arch and coronary branches of a silicone aorta during 1:1 and 1:2 intraaortic balloon support. Integration over time of the flow signals during inflation yielded Vcor and the distribution of Vtip.Results: In patients, Vroot was 6.4% ± 4.8% of the intraaortic balloon volume during 1:1 assistance and 10.0% ± 5.0% during 1:2 assistance. In vitro and with an artificial heart simulating the native heart, Vcor was smaller, 3.7% and 3.8%, respectively. The distribution of Vtip in vitro varied, with less volume displaced toward the arch and coronary branches and more volume stored in the compliant aortic wall when the artificial heart was not operating.Conclusion: The blood volume displaced toward the coronary circulation as the result of intraaortic balloon inflation is a small percentage of the nominal intraaortic balloon volume. Although small, this percentage is still a significant fraction of baseline coronary flow.

Laparoscopic diaphragmatic plication for diaphragmatic paralysis and eventration: An objective evaluation of short-term and midterm results - Corrected Proof

2010-01-18

Objectives: We sought to objectively assess our outcomes after laparoscopic diaphragmatic plication for symptomatic hemidiaphragmatic paralysis or eventration using a respiratory quality-of-life questionnaire and pulmonary function tests.Methods: We performed a retrospective review of all symptomatic patients with hemidiaphragmatic paralysis or eventration who underwent laparoscopic diaphragmatic plication from March 1, 2005, through August 31, 2008. Patients with primary neuromuscular disorders were excluded from our analysis. We collected St George's Respiratory Questionnaire scores (a respiratory quality-of-life questionnaire) and pulmonary function test results preoperatively and at 1 month and 1 year postoperatively. A 2-sided significance level of .05 was used for all statistical testing.Results: During the study period, 25 patients underwent laparoscopic diaphragmatic plication (9 right-sided and 16 left-sided plications); 1 patient required conversion to a thoracotomy. St George's Respiratory Questionnaire total scores (59.3 ± 26.8) improved by more than 20 points on average (a reduction of ≥4 points after an intervention is considered a clinically significant improvement). This improvement was statistically significant at 1 month (36.6 ± 15.9, P = .001) and maintained significance at 1 year (30.8 ± 18.8, P = .009). Similarly, percent predicted maximum forced inspiratory flow (93.2% ± 34.1%) was significantly improved 1 month after plication (113.9% ± 31.8%, P = .01) and maintained significance at 1 year (111.5% ± 30.9%, P = .02).Conclusions: Our objective evaluation of laparoscopic diaphragmatic plication for hemidiaphragmatic paralysis or eventration demonstrated significant short-term and midterm improvements in respiratory quality of life and pulmonary function test results. This approach represents a potential paradigm shift in the surgical management of hemidiaphragmatic paralysis or eventration.

Angiotensin II receptor type 1 is upregulated in atrial tissue of patients with rheumatic valvular disease with atrial fibrillation - Corrected Proof

Hongliang Cong, Ximing Li, Lijun Ma, Hua Jiang, Yongmin Mao, Meilin Xu — 2010-01-18

Objective: The purpose of this study was to examine the changes in expression of angiotensin II receptor type 1/2 in left or right atrial tissue from patients with rheumatic valvular disease with or without atrial fibrillation.Methods: Atrial tissue samples were obtained from 39 patients with rheumatic mitral valve disease during cardiac surgery. Among these patients, there were 25 with atrial fibrillation and 14 with sinus rhythm. The level of angiotensin II receptor type 1 or type 2 mRNA transcription was measured by means of a semiquantitative reverse transcription–polymerase chain reaction technique. Expression of angiotensin II receptor type 1 or type 2 protein was detected by means of immunohistochemistry assay and Western blot analysis.Results: The inner diameter of the left atrium was clearly enlarged in the atrial fibrillation group in comparison with that seen in the sinus rhythm group. The expression levels of both angiotensin II receptor type 1 mRNA and protein in the left atrial tissue were significantly increased in the patients with atrial fibrillation compared with those seen in patients with sinus rhythm (P < .05). Interestingly, the comparison of angiotensin II receptor type 2 expression levels in the left atrial tissue between these 2 groups is not statistically significant. In addition, the results of angiotensin II receptor type 1 or 2 expression in the right atrial tissue did not show any obvious change in the patients with atrial fibrillation versus those with sinus rhythm.Conclusions: Expression of angiotensin II receptor type 1 but not type 2 is highly upregulated only in the left atrial tissue of patients with rheumatic valvular disease with atrial fibrillation. This suggests that there is a possible pathophysiologic role of the renin–angiotensin system in patients with atrial fibrillation and that a series of effects mediated by the activation of angiotensin II receptor type 1 in the left atrial tissue might be one of the molecular mechanisms involved in the process of atrial remodeling in atrial fibrillation.

Are stentless valves hemodynamically superior to stented valves? Long-term follow-up of a randomized trial comparing Carpentier–Edwards pericardial valve with the Toronto Stentless Porcine Valve - Corrected Proof

2010-01-18

Objective: The benefit of stentless valves remains in question. In 1999, a randomized trial comparing stentless and stented valves was unable to demonstrate any hemodynamic or clinical benefits at 1 year after implantation. This study reviews long-term outcomes of patients randomized in the aforementioned trial.Methods: Between 1996 and 1999, 99 patients undergoing aortic valve replacement were randomized to receive either a stented Carpentier–Edwards pericardial valve (CE) (Edwards Lifesciences, Irvine, Calif) or a Toronto Stentless Porcine Valve (SPV) (St Jude Medical, Minneapolis, Minn). Among these, 38 patients were available for late echocardiographic follow-up (CE, n = 17; SPV, n = 21). Echocardiographic analysis was undertaken both at rest and with dobutamine stress, and functional status (Duke Activity Status Index) was compared at a mean of 9.3 years postoperatively (range, 7.5–11.1 years). Clinical follow-up was 82% complete at a mean of 10.3 years postoperatively (range, 7.5–12.2 years).Results: Preoperative characteristics were similar between groups. Effective orifice areas increased in both groups over time. Although there were no differences in effective orifice areas at 1 year, at 9 years, effective orifice areas were significantly greater in the SPV group (CE, 1.49 ± 0.59 cm2; SPV, 2.00 ± 0.53 cm2; P = .011). Similarly, mean and peak gradients decreased in both groups over time; however, at 9 years, gradients were lower in the SPV group (mean: CE, 10.8 ± 3.8 mm Hg; SPV, 7.8 ± 4.8 mm Hg; P = .011; peak: CE, 20.4 ± 6.5 mm Hg; SPV, 14.6 ± 7.1 mm Hg; P = .022). Such differences were magnified with dobutamine stress (mean: CE, 22.7 ± 6.1 mm Hg; SPV, 15.3 ± 8.4 mm Hg; P = .008; peak: CE, 48.1 ± 11.8 mm Hg; SPV, 30.8 ± 17.7 mm Hg; P = .001). Ventricular mass regression occurred in both groups; however, no differences were demonstrated between groups either on echocardiographic, magnetic resonance imaging, or biochemical (plasma B-type [brain] natriuretic peptide) assessment (P = .74). Similarly, Duke Activity Status Index scores of functional status improved in both groups over time; however, no differences were noted between groups (CE, 27.5 ± 19.1; SPV, 19.9 ± 12.0; P = .69). Freedom from reoperation at 12 years was 92% ± 5% in patients with CEs and 75% ± 5% in patients with SPVs (P = .65). Freedom from valve-related morbidity at 12 years was 82% ± 7% in patients with CEs and 55% ± 7% in patients with SPVs (P = .05). Finally, 12-year actuarial survival was 35% ± 7% in patients with CEs and 52% ± 7% in patients with SPVs (P = .37).Conclusion: Although offering improved hemodynamic outcomes, the SPV did not afford superior mass regression or improved clinical outcomes up to 12 years after implantation.

Use of carotid–subclavian arterial bypass and thoracic endovascular aortic repair to minimize cerebral ischemia in total aortic arch reconstruction - Corrected Proof

2010-01-18

Objective: Total aortic arch replacement typically requires hypothermic circulatory arrest, carrying risks of cerebral ischemia. We recently introduced left carotid–subclavian bypass before total aortic arch replacement with thoracic stent grafting to achieve hybrid arch reconstruction with short periods of selective antegrade cerebral perfusion.Methods: From 2004 to 2009, 332 patients underwent ascending aorta or arch replacements. Of these, 37 underwent total aortic arch replacement. In 2008, we began performing left carotid–subclavian bypass before subtotal arch replacement, with side-graft anastomoses to innominate and left carotid arteries. Patients then underwent aortic graft stent deployment to complete arch reconstruction. Twenty-eight patients underwent conventional arch replacement (group I); 9 underwent hybrid arch replacement (group II).Results: Selective antegrade cerebral perfusion time in group I was 33.3 ± 13.7 minutes versus 18.9 ± 9.2 minutes in group II (P = .007). Among group I patients, 82% required hypothermic circulatory arrest (vs 0% in group II, P < .001). Mean cardiopulmonary bypass and aortic crossclamp times were longer in group I than group II (P < .05). Incidence of neurologic complications was 14% in group I (4/28) versus 0% (0/9) in group II, although this finding did not reach statistical significance (P = .55).Conclusions: Left carotid–subclavian bypass before arch replacement with staged thoracic stent grafting to achieve hybrid arch reconstruction was associated with decreased selective antegrade cerebral perfusion, cardiopulmonary bypass, and aortic crossclamp times and eliminated hypothermic circulatory arrest. This technique may minimize neurologic complications associated with arch replacement and provide a viable hybrid approach to patients with arch aneurysms and dissections.

Discussion - Corrected Proof

2010-01-18

Dr John A. Kern (Charlottesville, Va). Dr Xydas, I congratulate you on a nice presentation and study. Looking back at your last 330-odd aortic patients, as you point out, 37 underwent TAAR procedures with good results. With the advent of endovascular technology, your group, like many groups, is getting creative in ways to minimize circulatory arrest times, minimize cerebral malperfusion times, and improve outcomes, and certainly with this study and this small group of patients you have done that. You have certainly demonstrated decreased CPB, crossclamp, and circulatory arrest times. I really have just a few questions, some of which are technical. Tell me about the CSB. Did you always do that concomitantly with the arch procedure, or did you do that a day or so before? In addition to that, because it appears that it is routine, because you are using the CSB to maintain carotid perfusion, did you necessarily image the head to define the cerebrovascular anatomy?

Discussion - Corrected Proof

2010-01-18

Dr Hartzell V. Schaff (Rochester, Minn). Thank you, Dr Miller, Dr Kron. I want to congratulate Dr Cohen on a beautiful presentation. He and his colleagues have provided important information on the 10-year follow-up of a comparative study of the stented and stentless valves. He has shown no difference in the mass regression when comparing the 2 groups. There is no real difference in hemodynamics, perhaps a 3-mm gradient, which was statistically significant but appears not to be clinically important. The most important feature is that there does not appear to be a difference in clinical outcome.

Balloon-guided, tapered, Polyflex stent guidance: An atraumatic technique for successful stent placement through tight, rigid airway stenoses - Corrected Proof

Moishe Liberman, John C. Wain — 2010-01-18

Benign airway strictures are often effectively treated with sequential dilation. However, when this is not successful, or in cases of frequent stricture recurrence, retrievable stenting can relieve symptoms as well as allow for airway remodeling, resulting in a less stenotic lumen. Anastomotic strictures are often difficult to dilate owing to fibrosis and suture reaction. Reoperation in these cases is often extremely challenging owing to the limited length of airway remaining after the first operation. In these cases, we prefer to use silicone stents after dilation to allow stricture remodeling. The Polyflex self-expanding polyester/silicone airway stent (Boston Scientific, Boston, Mass) works well for these challenging cases because it is completely covered, thin-walled, and does not contain any metallic elements.

Stage I Norwood: Optimal technical performance improves outcomes irrespective of preoperative physiologic status or case complexity - Corrected Proof

2010-01-14

Objective: Interplay of baseline physiologic status, case complexity, technical performance, and outcomes in high-acuity operations has been poorly defined. This study explored these interactions to determine whether a technically optimal operation can mitigate effects of baseline physiology and high case-complexity on outcomes for the stage I Norwood procedure.Methods: Technical performance was categorized as optimal, adequate, or inadequate from adequacy of the anatomic repair of the stage I subprocedures according to anatomic areas where intervention is performed. Physiological illness severity statuses in preoperative and postoperative periods were determined with Pediatric Risk of Mortality III system, which uses 17 physiologic variables. Case complexity was calculated with Aristotle comprehensive system. All patients undergoing stage I procedure from January 2004 to December 2007 were retrospectively studied.Results: One hundred thirty-five procedures were included. Five were excluded from the technical performance assessment because of inadequate postoperative data. Eighty-one (62.3%), 26 (20%), and 23 (17.7%), respectively, were scored as optimal, adequate, and inadequate. Overall hospital mortality was 14.1%. Inadequate technical performance, high-complexity Aristotle comprehensive scores, and high preoperative illness severity scores correlated with significantly higher hospital mortality, longer stay, and greater frequency of major postoperative complications. In subgroup analysis of patients with optimal technical performance, outcomes were favorable irrespective of high or low preoperative physiologic illness severity or case complexity.Conclusions: In stage I Norwood procedures, optimal technical performance attenuated effects of poor preoperative physiologic status and high case complexity, with reduced hospital mortality. Inadequate technical performance resulted in poor outcomes regardless of preoperative status.

Total aortic arch reconstruction with open placement of triple-branched stent graft for acute type A dissection - Corrected Proof

Liang-Wan Chen, Xiao-Fu Dai, Gui-Can Zhang, Lin Lu — 2010-01-14

In total arch replacement for acute type A aortic dissection, careful manipulations of the arch and elaborate anastomoses to the distal aortic and three arch vessels are time–consuming and could induce phrenic and recurrent laryngeal nerve injury. Moreover, performing anastomosis and hemostasis at the descending aorta and at the left subclavian artery is usually very difficult because of the deep surgical field. To reduce such problems, we applied a simple open triple-branched stent graft placement technique for total arch reconstruction.

Radiofrequency ablation for Barrett's esophagus and low-grade dysplasia in combination with an antireflux procedure: A new paradigm - Corrected Proof

2010-01-14

Objective: Radiofrequency ablation for Barrett's esophagus in combination with an antireflux procedure has not been widely documented. We report our initial experience with radiofrequency ablation in association with antireflux procedure for Barrett's metaplasia and low-grade dysplasia.Methods: A total of 14 patients (10 male and 4 female patients) presented with Barrett's metaplasia (n=11) or low-grade dysplasia (n=3). Median age was 60 years (38–80 years). The severity of Barrett's esophagus was classified by length (in centimeters), appearance (circumferential/noncircumferential), and histology (1, normal; 2, Barrett's metaplasia; and 3, low-grade dysplasia). Radiofrequency ablation was performed with the HALO 360° or 90° systems (BARRX Medical, Sunnyvale, Calif).Results: Median follow-up was 17 months. The mean number of ablative procedures undertaken was 2.6 (range, 1–6). There was no mortality, but there were 2 perioperative complications after the antireflux procedure (pneumonia, 1; atrial fibrillation, 1). One patient had mild dysphagia requiring a single dilation 2 months after ablation. The mean length of Barrett's esophagus decreased from 6.2 to 1.2cm after treatment (P=.001). Barrett's grade decreased significantly (P=.003). Before therapy, circumferential Barrett's esophagus was present in 13 patients. At last endoscopy, only 1 patient had circumferential Barrett's esophagus present. The number of radiofrequency ablation treatments was significantly (P < .05) associated with success. All patients receiving 3 or more treatments had complete resolution of Barrett's metaplasia.Conclusions: Radiofrequency ablation performed either before or after an antireflux procedure is safe. This approach is effective for reducing or eliminating metaplasia and dysplasia. Long-term studies will be necessary to determine whether this approach can provide durable control of both reflux and Barrett's esophagus.

How much septal–lateral mitral annular reduction do you get with new ischemic/functional mitral regurgitation annuloplasty rings? - Corrected Proof

Wolfgang Bothe, Julia C. Swanson, Neil B. Ingels, D. Craig Miller — 2010-01-14

Objective: Disproportionate reduction of the mitral septal–lateral annular dimension is the goal in the surgical treatment of ischemic or functional mitral regurgitation and avoids the need for ring “downsizing.” How much the new annuloplasty rings designed for patients with ischemic/functional mitral regurgitation reduce annular septal–lateral dimension, however, is proprietary information and debated.Methods: Outer and inner septal–lateral and commissure–commissure diameters of all available sizes of Edwards GeoForm, Edwards IMR ETlogix (both Edwards Lifesciences, Irvine, Calif), St Jude Medical Rigid Saddle Annuloplasty Ring (St Jude Medical, Inc, St Paul, Minn), and Medtronic Profile 3D (Medtronic, Minneapolis, Minn) annuloplasty rings with and without the fabric covering were measured with electronic calipers. These rings were compared with a Carpentier–Edwards Physio ring (Edwards Lifesciences) to assess the relative amount of septal–lateral and commissure–commissure dimension change. Average fractional changes (% ±1 standard deviation) versus the Physio ring were calculated.Results: The GeoForm provided the greatest outer septal–lateral reduction relative to Physio ring (−24% ± 2%), followed by the IMR ETlogix (−9% ± 2%) and Profile 3D (−8% ± 5%). The septal–lateral diameter of the Rigid Saddle Annuloplasty Ring was similar to that of the Physio ring (+1% ± 3%). Although commissure–commissure outer diameters of the IMR ETlogix, Rigid Saddle Annuloplasty Ring, and Profile 3D were similar to that of the Physio ring (0% ± 2%, +4% ± 3%, and +3% ± 4%, respectively), the GeoForm had a larger commissure–commissure dimension (+12% ± 2%). The inner diameter septal–lateral reductions were even more pronounced.Conclusions: Relative to the Physio ring, the GeoForm has the most outer and inner septal–lateral reduction but larger commissure–commissure dimension; the IMR ETlogix and Profile 3D provide a moderate degree of septal–lateral reduction without affecting commissure–commissure dimension, and Rigid Saddle Annuloplasty Ring septal–lateral and commissure–commissure diameters are similar to those of the Physio ring. Knowing the degree of disproportionate septal–lateral downsizing inherent in each ring type will help guide surgical decision making.

Clinical depression, posttraumatic stress disorder, and comorbid depression and posttraumatic stress disorder as risk factors for in-hospital mortality after coronary artery bypass grafting surgery - Corrected Proof

2010-01-14

Objective: The goal of this study was to examine the effect of clinical depression, posttraumatic stress disorder, and comorbid depression and posttraumatic stress disorder on in-hospital mortality after a coronary artery bypass grafting surgery. It is hypothesized that depression, posttraumatic stress disorder, and comorbid depression and posttraumatic stress disorder will independently contribute to an increased risk for in-hospital mortality rates after coronary artery bypass grafting surgery.Methods: We performed a retrospective analysis of the 2006 Nationwide Inpatient Sample database. The Nationwide Inpatient Sample database provides information on approximately 8 million US inpatient stays from about 1000 hospitals. We performed χ2 and unpaired t tests to evaluate potential confounding group demographic and medical variables. Hierarchic logistic regression was used with forced order entry of depression, posttraumatic stress disorder, and comorbid depression and posttraumatic stress disorder.Results: Deceased patients were more likely to have had depression (alive, 24.8%; deceased, 60.3%; P < .001), posttraumatic stress disorder (alive, 13.4%; deceased, 56.1%; P < .001), and cormorbid depression and posttraumatic stress disorder (alive, 7.8%; deceased, 48.5%; P < .001). After adjusting for potential confounding factors, patients with depression (odds ratio, 1.24; 95% confidence interval, 1.02–1.50), posttraumatic stress disorder (odds ratio, 2.09; 95% confidence interval, 1.65–2.64), and comorbid depression and posttraumatic stress disorder (odds ratio, 4.66; 95% confidence interval, 3.46–6.26) had an increased likelihood of in-hospital mortality compared with that seen in patients who were alive.Conclusions: Two findings were noteworthy. First, depression, posttraumatic stress disorder, and comorbid depression and posttraumatic stress disorder are prevalent in patients undergoing coronary artery bypass grafting procedures. Second, depression, posttraumatic stress disorder, and comorbid depression and posttraumatic stress disorder increase the risk of death by magnitudes comparable with well-established physical health risk factors after coronary artery bypass grafting surgery. The implications for clinical practice and future directions are discussed.

Lower graft patency after off-pump than on-pump coronary artery bypass grafting: An updated meta-analysis of randomized trials - Corrected Proof

Hisato Takagi, Masafumi Matsui, Takuya Umemoto — 2010-01-14

Our previous meta-analysis of randomized trials demonstrated a significant increase in overall graft occlusion, especially in saphenous vein graft occlusion, in off-pump coronary artery bypass grafting (CABG) compared with on-pump CABG. Since we conducted the meta-analysis, graft patency in several randomized trials has been reported. The likelihood of graft occlusion was no different between off-pump and on-pump CABG groups in a study by Angelini and associates, whereas Shroyer and collaborators revealed that the overall rate of graft patency was lower in the off-pump group than in the on-pump group. We performed an updated meta-analysis of graft patency after off-pump versus on-pump CABG from randomized trials.

Selective endothelin-1 receptor type A inhibition in subjects undergoing cardiac surgery with preexisting left ventricular dysfunction: Influence on early postoperative hemodynamics - Corrected Proof

2010-01-14

Objective: A robust release of endothelin-1 with subsequent endothelin-A subtype receptor activation occurs in patients after cardiac surgery requiring cardiopulmonary bypass. Increased endothelin-A subtype receptor activation has been identified in patients with poor left ventricular function (reduced ejection fraction). Accordingly, this study tested the hypothesis that a selective endothelin-A subtype receptor antagonist administered perioperatively would favorably affect post-cardiopulmonary bypass hemodynamic profiles in patients with a preexisting poor left ventricular ejection fraction.Methods: Patients (n = 29; 66 ± 2 years) with a reduced left ventricular ejection fraction (37% ± 2%) were prospectively randomized in a blinded fashion, at the time of elective coronary revascularization or valve replacement requiring cardiopulmonary bypass, to infusion of the highly selective and potent endothelin-A subtype receptor antagonist sitaxsentan at 1 or 2 mg/kg (intravenous bolus; n = 9, 10 respectively) or vehicle (saline; n = 10). Infusion of the endothelin-A subtype receptor antagonist/vehicle was performed immediately before separation from cardiopulmonary bypass and again at 12 hours after cardiopulmonary bypass. Endothelin and hemodynamic measurements were performed at baseline, at separation from cardiopulmonary bypass (time 0), and at 0.5, 6, 12, and 24 hours after cardiopulmonary bypass.Results: Baseline plasma endothelin (4.0 ± 0.3 fmol/mL) was identical across all 3 groups, but when compared with preoperative values, baseline values obtained from age-matched subjects with a normal left ventricular ejection fraction (n = 37; left ventricular ejection fraction > 50%) were significantly increased (2.9 ± 0.2 fmol/mL, P < .05). Baseline systemic (1358 ± 83 dynes/sec/cm−5) and pulmonary (180 ± 23 dynes/sec/cm−5) vascular resistance were equivalent in all 3 groups. As a function of time 0, systemic vascular resistance changed in an equivalent fashion in the post-cardiopulmonary bypass period, but a significant endothelin-A subtype receptor antagonist effect was observed for pulmonary vascular resistance (analysis of variance; P < .05). For example, at 24 hours post-cardiopulmonary bypass, pulmonary vascular resistance increased by 40 dynes/sec/cm−5 in the vehicle group but directionally decreased by more than 40 dynes/sec/cm−5 in the 2 mg/kg endothelin-A subtype receptor antagonist group (P < .05). Total adverse events were equivalently distributed across the endothelin-A subtype receptor antagonist/placebo groups.Conclusion: These unique findings demonstrated that infusion of an endothelin-A subtype receptor antagonist in high-risk patients undergoing cardiac surgery was not associated with significant hemodynamic compromise. Moreover, the endothelin-A subtype receptor antagonist favorably affected pulmonary vascular resistance in the early postoperative period. Thus, the endothelin-A subtype receptor serves as a potential pharmacologic target for improving outcomes after cardiac surgery in patients with compromised left ventricular function.

Preoperative very short-term, high-dose erythropoietin administration diminishes blood transfusion rate in off-pump coronary artery bypass: A randomized blind controlled study - Corrected Proof

2009-12-30

Objective: Human recombinant erythropoietin has been used to obtain a rapid increase in red blood cells before surgery. Previously, the shortest preparatory interval has been 4 days, but at the European Hospital only 2.4 days on average separate hospitalization and surgery. We therefore proposed a randomized blind trial to test the efficacy of high-dose erythropoietin for very short-term administration.Methods: All patients presenting with a diagnosis of isolated coronary vessel disease were randomized to either erythropoietin therapy or a control group. Patients with a creatinine level greater than 2 mg/dL or hemoglobin level greater than 14.5 g/dL were excluded. Hemoglobin values were collected preoperatively and on postoperative days 1 and 4. Blood loss and blood transfusion rate were recorded at the time of discharge.Results: We enrolled 320 consecutive patients in the study. No significant difference was found in preoperative parameters, postoperative blood loss, or mean preoperative hemoglobin levels. On postoperative day 4, mean hemoglobin was 15.5% higher in the erythropoietin group (10.70 ± 0.72 g/dL vs 9.26 ± 0.71 g/dL; P < .05). This group required 0.33 units of blood per patient, whereas the controls required 0.76 units per patient (risk ratio 0.43, P = .008).Conclusion: A significant reduction in transfusion rate and a significant increase in hemoglobin values were observed in the erythropoietin group. No adverse events related to erythropoietin administration were recorded. A very short preoperative erythropoietin administration seems to be a safe and easy method to reduce the need for blood transfusions.

Discussion - Corrected Proof

2009-12-30

Dr C. Koch (Cleveland, Ohio). You present intriguing data demonstrating reduced red cell transfusion in patients receiving very short-term use of erythropoietin. I have 3 questions for you, and they pertain to the timing of administration, adverse events, and cost.

Nonoperative thoracic duct embolization for traumatic thoracic duct leak: Experience in 109 patients - Corrected Proof

2009-12-30

Objective: To demonstrate the efficacy of a minimally invasive, nonoperative, catheter-based approach to the treatment of traumatic chyle leak.Methods: A retrospective review of 109 patients was conducted to assess the efficacy of thoracic duct embolization or interruption for the treatment of high-output chyle leak caused by injury to the thoracic duct.Results: A total of 106 patients presented with chylothorax, 1 patient presented with chylopericardium, and 2 patients presented with cervical lymphocele. Twenty patients (18%) had previous failed thoracic duct ligation. In 108 of 109 patients, a lymphangiogram was successful. Catheterization of the thoracic duct was achieved in 73 patients (67%). In 71 of these 73 patients, embolization of the thoracic duct was performed. Endovascular coils or liquid embolic agent was used to occlude the thoracic duct. In 18 of 33 cases of unsuccessful catheterization, thoracic duct needle interruption was attempted below the diaphragm. Resolution of the chyle leak was observed in 64 of 71 patients (90%) post-embolization. Needle interruption of the thoracic duct was successful in 13 of 18 patients (72%). In 17 of the 20 patients who had previous attempts at thoracic duct ligation, embolization or interruption was attempted and successful in 15 (88%). The overall success rate for the entire series was 71% (77/109). There were 3 (3%) minor complications.Conclusion: Catheter embolization or needle interruption of the thoracic duct is safe, feasible, and successful in eliminating a high-output chyle leak in the majority (71%) of patients. This minimally invasive, although technically challenging, procedure should be the initial approach for the treatment of a traumatic chylothorax.

Discussion - Corrected Proof

2009-12-30

Dr N. Altorki (New York, NY). I have no disclosures. Dr Itkin, I want to congratulate your group, but especially Dr Cope, for developing this in 1998, perfecting it, and really advocating it. For decades the treatment of choice for high-volume chylous fistula has been surgical ligation of the thoracic duct, and over the years several important lessons have been learned. Foremost among these lessons is the need for prompt return to the operating room, usually within 7 or no more than 10 days from the index procedure, to avoid the deleterious effects of nutritional and immunologic depletion.

The effectiveness of prestorage leukocyte-reduced red blood cell transfusion on perioperative inflammatory response with a miniaturized biocompatible bypass system - Corrected Proof

2009-12-28

Objective: Since 2007, the Japanese Red Cross Blood Center has provided prestorage leukocyte-reduced red blood cell concentrates in which the leukocytes were reduced soon after collection. We have established a miniaturized bypass system (140 mL) to reduce the perioperative inflammatory responses. This study was designed to reveal the effectiveness of leukocyte-reduced red blood cell concentrate transfusion on perioperative inflammatory responses in pediatric cardiac surgery.Methods: Between May 2006 and June 2008, 50 consecutive patients weighing less than 5 kg who underwent a surgical procedure with red blood cell concentrate transfusion using a miniaturized bypass system were reviewed retrospectively. Twenty-five patients before 2007 received stored red blood cell concentrate in which leukocytes were reduced with a filter just before transfusion (group A). After 2007, 25 patients received the prestorage leukocyte-reduced red blood cell concentrate transfusion (group B). The postoperative peak C-reactive protein level, peak white blood cell count, peak neutrophil count, percentage body weight gain, inotrope score, plasma lactate concentration, postoperative mechanical ventilation time, and length of intensive care unit stay were compared as the perioperative inflammatory response and morbidity for both groups.Results: There were no significant differences in peak white blood cell count, peak neutrophil count, percentage body weight gain, and inotrope score between the groups. The peak C-reactive protein level in group A was significantly greater than that in group B (6.7 ± 4.7 vs 4.2 ± 3.6 mg/dL, P < .05). The lactate concentration at 12 and 24 hours after surgical intervention in group A was significantly greater than that in group B (3.1 ± 2.5 vs 1.9 ± 1.1 mmol/L [P < .05] and 2.2 ± 0.2 vs 1.4 ± 0.2 mmol/L [P < .05], respectively). The postoperative mechanical ventilation time and intensive care unit stay in group A were significantly greater than those in group B (5.9 ± 7.4 vs 2.1 ± 2.0 days [P < .05] and 9.8 ± 7.9 vs 5.0 ± 2.1 days [P < 0.05], respectively). Multivariate analyses showed that the leukocyte-reduced red blood cell concentrate transfusion reduced the peak C-reactive protein level (in milligrams per deciliter; coefficient, −2.95; 95% confidence interval [CI], −4.66 to −0.93; P = .003), postoperative mechanical ventilation time (in days; coefficient, −3.41; 95% CI, −6.07 to −0.74; P = .013), and intensive care unit stay (in days; coefficient, −4.51; 95% CI, −7.37 to −1.64; P = .003).Conclusions: Our study revealed that in neonates and small infants, compared with transfusions with stored red blood cell concentrate, transfusion of leukocyte-reduced red blood cell concentrates was associated with reduced perioperative inflammatory responses and improved clinical outcomes.

Electron transport chain dysfunction in neonatal pressure-overload hypertrophy precedes cardiomyocyte apoptosis independent of oxidative stress - Corrected Proof

2009-12-28

Objectives: We have previously shown in a model of pressure-overload hypertrophy that there is increased cardiomyocyte apoptosis during the transition from peak hypertrophy to ventricular decompensation. Electron transport chain dysfunction is believed to play a role in this process through the production of excessive reactive oxygen species. In this study we sought to determine electron transport chain function in pressure-overload hypertrophy and the role of oxidative stress in myocyte apoptosis.Methods and Results: Neonatal rabbits underwent thoracic aortic banding at 10 days of age. Compensated hypertrophy (4 weeks of age), decompensated hypertrophy (6 weeks of age), and age-matched controls (n = 4–8 per group) as identified by serial echocardiography were studied. Electron transport chain complex activities were determined by spectophotometry in isolated mitochondria. Complex I was significantly decreased (P = .005) at 4 weeks and further decreased at 6 weeks (P = .001). Complex II was significantly decreased at both time points (4 weeks, P = .003; 6 weeks, P = .009). However, hyddrogen peroxide production, measured in isolated mitochondria by fluorescence spectroscopy, was significantly decreased at 4 weeks of age in banded animals compared with controls (P = .038), and mitochondrial DNA oxidative damage (measurement of 8- hydroxydeoxyguanosine by enzyme-linked immunosorbent assay) was also significantly decreased at 4 weeks of age (P = .031). Mitochondrial activated apoptosis was determined by Bax/Bcl-2 ratios (immunoblotting). Bax/Bcl-2 levels were significantly increased in banded animals at 6 weeks.Conclusions: In pressure-overload hypertrophy, the transition from compensated left ventricular hypertrophy to failure and cardiomyocyte apoptosis is preceded by mitochondrial complex I and II dysfunction followed by an increase in Bax/Bcl-2 ratios. The mechanism of apoptosis initiation is independent of increased oxidative stress.

A new instrument of suction support adapter system for epicardial radiofrequency ablation - Corrected Proof

Shinichi Kadoya, Go Watanabe, Yoshinao Koshida, Makoto Oda, Shojiro Yamaguchi — 2009-12-28

Objective: Recently, epicardial ablation on a beating heart has been conducted as a minimally invasive surgical procedure for atrial fibrillation. We have developed a suction support adapter with the aim of ensuring contact between the ablation probe and the atrial wall to obtain transmural coagulation, and we evaluated the effectiveness of the adapter in electrophysiologic and histopathologic procedures.Methods: To ensure contact between the radiofrequency ablation probe and the atrial wall, we designed and fabricated a suction support adapter. Twelve pigs were used in this study. A comparison was made between a group in which the ablation probe alone was used (group C, n = 6) and a group in which the ablation probe was used with the adapter (group S, n = 6). In both groups, epicardial ablation was conducted on a beating heart. An electrophysiologic evaluation was conducted to determine whether there was electrical isolation. Histopathologic evaluations were performed to identify the range of coagulation in the resected atrial wall specimens.Results: The coagulation range was significantly deeper in group S than in group C, and the breadth was significantly narrower. Transmural coagulation and electrical isolation of the atrial wall were seen in 1 case in group C and in all cases in group S.Conclusions: Using the suction support adapter, we were able to maintain good contact between the ablation probe and the atrial wall. This device is thus thought to be useful for the safe and reliable performance of epicardial ablation on a beating heart.

Type B thymoma: Is prognosis predicted only by World Health Organization classification? - Corrected Proof

2009-12-28

Objective: The prognostic relevance of subtypes within type B thymomas is controversial. The objective of this study was to evaluate the utility of World Health Organization (WHO) classification in patients with type B thymoma.Methods: This was a retrospective review of 100 patients who underwent thymectomy for WHO type B thymoma. Recurrence patterns and survival were compared among subtypes.Results: There were 22 type B1 tumors, 43 type B2 tumors, and 35 type B3 tumors. Incomplete resection occurred in 5 patients with type B1 thymoma, 8 with type B2 thymoma, and 8 with type B3 thymoma (P = .87). Of the 79 patients with complete resection, tumor recurrence occurred in 1 (5.9%) patient with type B1 thymoma, 2 (5.7%) with type B2 thymoma, and 2 (7.4%) with type B3 thymoma, and all of these patients had Masaoka stage III disease. Disease-free survival at 5 years was 93%, 85%, and 82% in type B1, B2, and B3, respectively (B1 vs B2; P = .79; B2 vs B3; P = 0.6). Disease-free survival at 5 years was 94%, 100%, 61% ,and 50% in Masaoka stages I, II, III, and IV, respectively (I vs II; P = .26; II vs III; P = .028; III vs IV; P = .002).Conclusions: Tumor recurrence was significantly associated with advanced Masaoka stage regardless of the WHO subtype of type B thymomas. Given the heterogeneity of WHO type B thymomas, Masaoka stage should always be considered when predicting prognosis and planning adjuvant treatment for patients with type B thymomas.

Four-arm robotic lobectomy for the treatment of early-stage lung cancer - Corrected Proof

2009-12-28

Objectives: We investigated the feasibility and safety of four-arm robotic lung lobectomy in patients with lung cancer and described the robotic lobectomy technique with mediastinal lymph node dissection.Methods: Over 21 months, 54 patients underwent robotic lobectomy for early-stage lung cancer at our institute. We used a da Vinci Robotic System (Intuitive Surgical, Inc, Mountain View, Calif) with three ports plus one utility incision to isolate hilum elements and perform vascular and bronchial resection using standard endoscopic staplers. Standard mediastinal lymph node dissection was performed subsequently. Surgical outcomes were compared with those in 54 patients who underwent open surgery over the same period and were matched to the robotic group using propensity scores for a series of preoperative variables.Results: Conversion to open surgery was necessary in 7 (13%) cases. Postoperative complications (11/54, 20%, in each group) and median number of lymph nodes removed (17.5 robotic vs 17 open) were similar in the 2 groups. Median robotic operating time decreased by 43 minutes (P = .02) from first tertile (18 patients) to the second-plus-third tertile (36 patients). Median postoperative hospitalization was significantly shorter after robotic (excluding first tertile) than after open operations (4.5 days vs 6 days; P = .002).Conclusions: Robotic lobectomy with lymph node dissection is practicable, safe, and associated with shorter postoperative hospitalization than open surgery. From the number of lymph nodes removed it also appears oncologically acceptable for early lung cancer. Benefits in terms of postoperative pain, respiratory function, and quality of life still require evaluation. We expect that technologic developments will further simplify the robotic procedure.

Effects of surgical ventricular reconstruction on diastolic function at midterm follow-up - Corrected Proof

2009-12-28

Objective: Limited data are available on the effects of surgical ventricular reconstruction on diastolic function. The aim of the present study was to evaluate changes in diastolic function induced by surgical ventricular reconstruction at 2 time intervals after surgery (discharge and follow-up) and to assess the impact of diastolic changes on clinical outcome.Methods: A total of 129 patients (65 ± 9 years, 14 women) underwent echocardiographic Doppler evaluation before surgical ventricular reconstruction, at discharge, and at follow-up (median 7 months). Patients with mitral regurgitation were excluded. Diastolic pattern was graded as follows: 0 (normal), 1 (abnormal relaxation), 2 (pseudo normalization), 3 (restrictive, reversible), and 4 (restrictive, irreversible).Results: At follow-up, 28 (21.7%) of 129 patients showed a restrictive diastolic pattern (grade 3–4; group 1) and 101 did not (diastolic pattern grade 0–2; group 2). Preoperative and postoperative factors strongly associated with late diastolic restriction included sphericity index (higher in group 1), ventricular shape (nonaneurysmal shape more frequent in group 1), internal dimensions (greater in group 1), diastolic pattern (higher in group 1), ejection fraction (lower in group 1); left atrial dimensions (greater in group 1); mitral regurgitation rate (higher in group 1). At multivariate analysis the most powerful predictors of restriction were preoperative pseudonormalization of diastolic pattern (diastolic pattern 2) and septolateral dimensions (short axis). Overall, ejection fraction improved from 33% ± 9% to 40% ± 9% to 40% ± 9%; P = .001; end-diastolic and end-systolic volumes decreased (112 ± 41 to 73 ± 21 to 88 ± 28mL/m2, respectively; P = .001; and 77 ± 38 to 44 ± 17 to 52 ± 24mL/m2, respectively; P = .001); New York Heart Association class improved (2.4 ± 0.8 to 1.6 ± 0.6; P = .001).Conclusions: Mild preoperative diastolic dysfunction (pseudonormalized pattern) and increased septolateral dimensions are independent predictors of diastolic restriction after surgical ventricular reconstruction.

In vivo functional flowmetric behavior of the radial artery graft: Is the composite Y-graft configuration advantageous over conventional aorta–coronary bypass? - Corrected Proof

2009-12-28

Introduction: Intraoperative flowmetric results of different configurations (Y-graft or aorta–coronary) of radial artery grafts have been poorly investigated.Methods: We report the results of an observational study designed to analyze transit-time flow measurements at baseline and during 1:1 intra-aortic balloon pumping in 114 consecutive patients receiving the radial artery as a aorta–coronary bypass (group A, 72 patients) or as a Y-graft with the left internal thoracic artery (group B, 42 patients). Graft flow reserve, recruited by 1:1 intra-aortic balloon pumping) greater than 1 indicated recruitment of surplus graft flow. Results were stratified by grafted territory and surgical technique.Results: Hospital outcome was comparable. Baseline transit-time flow results were similar between the 2 groups in terms of maximum diastolic flow, minimum systolic flow, mean flow, and pulsatility index. Graft flow reserve was not recruited by intra-aortic balloon pumping in 3 (2.7%) malfunctioning single aorta–oronary radial artery bypass grafts (P = .005 versus successful radial artery bypass grafts). Graft flow reserve was recruited (>1) by intra-aortic balloon pumping in the remaining 111 patent radial artery bypass grafts. Y-grafts showed higher maximum diastolic flow P < .0001), mean flow (P < .0001), graft flow reserve (P < .0001), percentage improvement of maximum diastolic flow (P < .0001), and of mean flow (P < .0001) compared with aorta–coronary radial artery bypass grafts. These results were confirmed for the right coronary (P ≤ .004) and the circumflex territory (P ≤ .001), for off-pump (P ≤ .008) or cardiopulmonary bypass (P < .0001) and for patients undergoing isolated bypass grafting (P < .0001).Conclusions: Intraoperative flows of radial artery bypass grafts showed comparable baseline results in single aorta–coronary conduits and Y-grafts. Graft flow reserve recruited by intra-aortic balloon pumping was higher in Y-conduits, regardless of the grafted territory and the perfusion strategy chosen. Failed radial artery bypass grafts did not improve transit-time flow results during 1:1 intra-aortic balloong pumping nor showed any recruitment of graft flow reserve.

The successful application of simulation-based training in thoracic surgery residency - Corrected Proof

2009-12-28

Objective: We developed and tested a clinical simulation program in the principles and conduct of cardiopulmonary bypass with the aim of improving confidence and proficiency in this critical aspect of cardiac surgical care.Methods: Fifteen residents from 6 resident-training programs who reported no prior cardiopulmonary bypass observation or simulation-based perfusion experience participated in a cardiopulmonary bypass course involving both didactic lectures and hands-on simulation. A computer-controlled hydraulic model of the human circulation was used in a specifically designed multidisciplinary simulation center environment to give the participants hands-on training with both basic operations and specific perfusion crisis scenarios. Pretraining and posttraining assessments concerning confidence, knowledge, and applications with regard to cardiopulmonary bypass were administered and compared.Results: Likert scale scores on confidence-related items increased significantly (P < .001), from 59% ± 16% to 92% ± 8%. Pretraining versus posttraining scores (72% ± 14%) on similar cognitive items were not significantly different (P=.3636). Scores on similar open-ended application items before and after training improved from 62% ± 25% to 85±10% (P < .0001). All subjects agreed that simulation-based cardiopulmonary bypass training was superior to classroom- and clinic-based education and that the scenarios enhanced their learning experience.Conclusions: Simulation-based cardiopulmonary bypass training appears to be an effective technique to build the confidence of thoracic surgery residents regarding knowledge and applications. Scenario-based practice in a specifically designed simulated environment is a valuable adjunct to traditional educational methods and has the potential to improve the training of thoracic residents.

Avoiding cardiopulmonary bypass in extracardiac cavopulmonary connection: Does it really matter? - Corrected Proof

2009-12-28

Objectives: We examined the effect of avoiding cardiopulmonary bypass on the early outcome variables after fenestrated extracardiac total cavopulmonary connection.Methods: Between May 2001 and January 2009, 102 patients with univentricular heart physiology underwent fenestrated extracardiac total cavopulmonary connection. Patients were divided into one of 2 groups: the cardiopulmonary bypass (n = 48) group and the no cardiopulmonary bypass (n = 54) group. In both groups there were patients with primary and staged fenestrated extracardiac total cavopulmonary connection. Duration of mechanical ventilation, pleural effusion, hemodynamic status, incidence of arrhythmia, and mortality were compared between the 2 groups.Results: Both groups were matched, except for more cases of tricuspid atresia in the no cardiopulmonary bypass group (P = .014) compared with other diagnostic morphologies and higher preoperative hemoglobin levels in the no cardiopulmonary bypass group (P = .01). Avoiding cardiopulmonary bypass did not reveal any significant effect on postoperative outcomes. A cardiopulmonary bypass time of more than 120 minutes caused not only a meaningful increase in the mean of mechanical ventilation duration (35 ± 9.6 vs 13 ± 2.1 hours, P = .026) but also increased the incidence of mechanical ventilation for more than 12 hours (P = .04). Bypass time of more than 120 minutes did not have influence on any other postoperative variables.Conclusion: Avoiding cardiopulmonary bypass in fenestrated extracardiac total cavopulmonary connection had no direct effect on the early outcome variables.

Sustained local application of epidermal growth factor to accelerate reepithelialization of tracheal grafts - Corrected Proof

2009-12-28

Objective: Epidermal growth factor–loaded gelatin microspheres were tested for potential to accelerate tracheal allograft reepithelialization.Methods: Epidermal growth factor–loaded gelatin microspheres were prepared by optimal double-phase emulsified condensation polymerization. One hundred age-matched allogeneic mice were randomly allocated to local administration of 1 mg epidermal growth factor–loaded gelatin microspheres (containing 1 μg epidermal growth factor), 1 mg gelatin microspheres, 1 μg epidermal growth factor, or nothing (control, all groups n = 25) during orthotopic transplant of C57BL/6 donor tracheal segments into BALB/c recipients without immunosuppressors. On days 7, 14, 21, 35, and 52 after transplant, 5 mice per group were killed and evaluated by histologic assessment and scanning electronic microscopy for reepithelialization and fibrosis of tracheal grafts.Results: Mean diameter of gelatin microspheres was 107 μm. Microspheres could not be fully degraded until 35 days after transplant in vivo. On days 7, 14, and 21, epithelium score and ratio of lamina propria to tracheal cartilage were not statistically different between mice with epidermal growth factor–loaded gelatin microspheres and other groups. On days 35 and 52, however, epithelium score was higher and ratio of lamina propria to tracheal cartilage was lower in epidermal growth factor–loaded gelatin microsphere recipients; these mice also had almost complete differentiation of regenerated epithelium into ciliated columnar epithelium on days 35 and 52, earlier than in other groups.Conclusions: Gelatin microspheres act as a functional vector for epidermal growth factor. Sustained local application of epidermal growth factor could accelerate reepithelialization of tracheal allografts.

Treatment of irradiated poststernotomy sternal nonunion with autologous stem cell–impregnated bone matrix and sternal plating - Corrected Proof

Tomasz A. Timek, Stuart B. Goodman, Richard I. Whyte — 2009-12-28

Sternal wound complications are an infrequent but significant cause of postoperative morbidity for cardiothoracic surgical patients. Sternal nonunion occurs in fewer than 1% of patients after median sternotomy, but it represents a challenging clinical problem because it is often associated with chronic pain of debilitating magnitude. Affected patients are often treated with débridement and sternal rewiring, which requires reexploration of the mediastinum. We describe the case of a patient successfully treated with an autologous stem cell–seeded bone matrix and sternal plating for chronic manubrial nonunion in a postsurgical, irradiated sternum.