Anatomical Variations of Pulmonary Artery and Associated Cardiac Defects in Tetralogy of Fallot

Objective: To determine pulmonary artery variations and other associated cardiac defects in patients with Tetralogy of Fallot (TOF). Study Design: Cross-sectional, descriptive study. Place and Duration of Study: The Children's Hospital and the Institute of Child Health, Lahore, from April 2006 to October 2007. Methodology: All patients with TOF, who underwent cardiac catheterization during this period, were included. Standard cine-angiograms were recorded and pulmonary artery sizing was done using z-scoring. Results: A total of 216 patients with TOF were catheterized. Pulmonary Artery (PA) abnormalities were present in 84 (38.9%) patients. The commonest abnormality was isolated Left Pulmonary Artery (LPA) stenosis (n=27, 32.14%) followed by isolated hypoplasia of Main Pulmonary Artery (MPA) (n=18, 21.43%) and supra-valvular stenosis in (n=11, 13.1%) patients. LPA was absent in one patient, while 2 patients had both absent right and left PA with segmental branch pulmonary arteries originating directly from MPA. Associated cardiac lesions included right aortic arch in 34 (15%), additional muscular VSD vary in 13 (5.5%), Patent Ductus Arteriosus (PDA) in 11 (6%) and Major Aortopulmonary Collateral Arteries (MAPCA) in 2 (1.9%) patients. Significant coronary artery abnormality was present in 10 (4.6%) children. Conclusion: Pulmonary artery abnormalities were present in 38.9% of patients with TOF Isolated LPA origin stenosis and MPA hypoplasia were the most common abnormalities. Significant associated cardiac lesions were present in one-third of the patients and included PDA, additional muscular VSD, coronary artery abnormalities and MAPCA.