Clinical implications of major aortopulmonary collateral arteries in patients with right isomerism.

BACKGROUND: The presence of major aortopulmonary collateral arteries (MAPCA) in patients with right isomerism may alter the prognosis, which is still unclear.

METHODS: From 1994 to 2003, 138 out of 155 patients (89%) with right isomerism had pulmonary stenosis or pulmonary atresia and constituted the study population.

RESULTS: Two groups of patients were identified, one with MAPCA and the other without. The MAPCA originating from descending thoracic aorta or aortic arch was noted in 9 patients (6.5%), with a median number of MAPCA being 3 (range, 2 to 4). Patients with MAPCA commonly had congestive heart failure (8/9, 89%) and frequent lower airway infection (6/9, 67%). In comparison with patients with MAPCA and without, the intrapericardial pulmonary artery was more frequently absent (2 of 9 vs 1 of 129, p < 0.001), and the pulmonary arterial size was smaller (McGoon ratio <1.5, 8 of 9 vs 57 of 129, p = 0.009) in the MAPCA group. The mean pulmonary arterial pressure measured was often higher than the suggested limit for Fontan circulation. Major aortopulmonary collateral arteries were addressed at a median of 6 months old (2 to 19 months old) in 5 patients. Although surgical mortality was not different for first-stage palliation and Glenn shunt in both groups, total cavopulmonary connection could only be performed in one patient with MAPCA with poor results. However, the 5-year survival of patients with and without MAPCA was not statistically different (74.1% vs 55.2%, p = 0.19).

CONCLUSIONS: The presence of MAPCA was uncommon but still noted in patients with right isomerism. It may cause heart failure and a less favorable pulmonary vasculature for a complete Fontan-type operation.