Fontan hemodynamics: Importance of pulmonary artery diameter

Dasi, Lakshmi P.; KrishnankuttyRema, Resmi; Kitajima, Hiroumi D.; Pekkan, Kerem; Sundareswaran, Kartik S.; Fogel, Mark; Sharma, Shiva; Whitehead, Kevin; Kanter, Kirk; Yoganathan, Ajit P.

doi:10.1016/j.jtcvs.2008.04.036

« Previous Next »The Journal of Thoracic and Cardiovascular Surgery
Volume 137, Issue 3 , Pages 560-564, March 2009

Fontan hemodynamics: Importance of pulmonary artery diameter

Lakshmi P. Dasi, PhD
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga
- Contributed equally.
Resmi KrishnankuttyRema, MS
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga
- Contributed equally.
Hiroumi D. Kitajima, PhD
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga
Kerem Pekkan, PhD
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga
- Currently working in the Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pa.
Kartik S. Sundareswaran, MS
- Children's Healthcare of Atlanta, Atlanta, Ga
Mark Fogel, MD
- Children's Hospital of Philadelphia, Philadelphia, Pa
Shiva Sharma, MD
- Pediatric Cardiology Services, Lawrenceville, Ga
Kevin Whitehead, MD, PhD
- Children's Hospital of Philadelphia, Philadelphia, Pa
Kirk Kanter, MD
- Children's Healthcare of Atlanta, Atlanta, Ga
- Emory University School of Medicine, Atlanta, Ga
Ajit P. Yoganathan, PhD
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Ga
- Address for reprints: Ajit P. Yoganathan, PhD, Wallace H. Coulter School of Biomedical Engineering, Georgia Institute of Technology, Room 2119 U.A. Whitaker Building, 313 First Dr. Atlanta, GA 30332-0535.

Received 30 November 2007; received in revised form 29 February 2008; accepted 4 April 2008.

Objective

We quantify the geometric and hemodynamic characteristics of extracardiac and lateral tunnel Fontan surgical options and correlate certain anatomic characteristics with their hemodynamic efficiency and patient cardiac index.

Methods and Results

The study was conducted retrospectively on 22 patients undergoing Fontan operations (11 extracardiac and 11 lateral tunnel operations). Total cavopulmonary connection geometric parameters such as vessel areas, curvature, and offsets were quantified using a skeletonization method. Energy loss at the total cavopulmonary connection junction was available from previous in vitro experiments and computational fluid dynamic simulations for 5 and 9 patients, respectively. Cardiac index data were available for all patients. There was no significant difference in the mean and minimum cross-sectional vessel areas of the pulmonary artery between the extracardiac and lateral tunnel groups. The indexed energy dissipation within the total cavopulmonary connection was strongly correlated to minimum cross-sectional area of the pulmonary arteries (R² value of 0.90 and P < .0002), whereas all other geometric features, including shape characteristics, had no significant correlation. Finally, cardiac index significantly correlated with the minimum pulmonary artery area (P = .006), suggesting that total cavopulmonary connection energy losses significantly affect resting cardiac output.

Conclusions

The minimum outlet size of the total cavopulmonary connection (ie, minimum cross section of pulmonary artery) governs the energy loss characteristics of the total cavopulmonary connection more strongly than variations in the shapes corresponding to extracardiac and lateral tunnel configurations. Differences in pulmonary artery sizes must be accounted for when comparing energy losses between extracardiac and lateral tunnel geometries.

CTSNet classification: 18, 21, 26

Abbreviations and Acronyms: BSA, body surface area, CFD, computational fluid dynamics, CHOA, Children's Healthcare of Atlanta, CHOP, Children's Hospital of Philadelphia, EC, extracardiac, IVC, inferior vena cava, LPA, left pulmonary artery, LT, lateral tunnel, MRI, magnetic resonance imaging, PA, pulmonary artery, RPA, right pulmonary artery, SVC, superior vena cava, TCPC, total cavopulmonary connection