Larger aortic reconstruction corresponds to diminished left pulmonary artery size in patients with single-ventricle physiology
Received 21 February 2009; received in revised form 24 June 2009; accepted 10 August 2009. published online 02 November 2009.
Background
Pulmonary artery size is a crucial determinant of hemodynamic energy loss in total cavopulmonary connections. We investigated the effect of aortic arch reconstruction on left pulmonary artery size based on their anatomic proximity.
Methods
Thirty-two patients undergoing the Fontan operation, 16 with hypoplastic left heart syndrome and 16 with non–hypoplastic left heart syndrome, were selected from the multicenter Fontan magnetic resonance imaging database at the Georgia Institute of Technology. The 16 datasets were consecutive with full anatomic reconstructions of the total cavopulmonary connection and aortic arch with no artifacts. The size of the aorta along the transverse arch and left pulmonary artery size in the region below the aortic arch was quantified by using a previously validated skeletonization technique.
Results
The transverse aortic and left pulmonary artery measurements (median, maximum, and minimum, respectively) for non–hypoplastic left heart syndrome were 2.2, 3.1, and 1.5 cm/m and 1.2, 1.6, and 0.2 cm/m, respectively, compared with 2.5, 4.1, and 2.0 cm/m and 0.9, 1.5, and 0.4 cm/m for patients with hypoplastic left heart syndrome. Thus the transverse aortic diameter of patients with hypoplastic left heart syndrome was, on average, 24% greater than that for patients with non–hypoplastic left heart syndrome (P < .05), whereas the left pulmonary artery diameter of patients with hypoplastic left heart syndrome was smaller than that of patients with non–hypoplastic left heart syndrome (P < .05). Regression analysis showed a significant negative correlation (P < .05) between aortic and left pulmonary artery diameters in both the hypoplastic left heart syndrome and non–hypoplastic left heart syndrome groups. However, when the study population was regrouped into reconstructed aorta and nonreconstructed aorta groups, the negative correlation was only significant for patients with reconstructed aortas, regardless of ventricular pathology (P < .02).
Conclusions
Stage 1 aortic reconstruction procedures that result in a large aorta limit left pulmonary artery size in patients undergoing the Fontan operation.
cDivision of Cardiology, Children's Hospital of Philadelphia, Philadelphia, Pa
Address for reprints: Ajit P. Yoganathan, PhD, Wallace H. Coulter School of Biomedical Engineering, Georgia Institute of Technology and Emory University, Room 2119 U. A. Whitaker Building, 313 Ferst Dr, Atlanta, GA 30332-0535.
Lakshmi P. Dasi's current affiliation is Department of Mechanical Engineering, Colorado State University, Fort Collins, Colo.
Disclosures: None.
We gratefully acknowledge the Bioengineering Research Partnership (BRP) grant from the National Institutes of Health (HL67622).
ABSTRACT