22q.11: a Risk Factor for Left Pulmonary Artery Hypoplasia in Congenital Heart Disease

Abstract

BACKGROUND: Individuals with 22q11 deletion syndrome have a mutation in the TBX1 gene. This is associated with reduced left pulmonary artery/right pulmonary artery ratio in animal models and in humans with structurally normal hearts. METHOD: A retrospective analysis was undertaken of patients who underwent surgical repair of Tetralogy of Fallot, truncus arteriosus, and interrupted aortic arch between 01/2007 and 12/2022. The left pulmonary artery/right pulmonary artery ratio on initial and most recent echocardiogram and initial and subsequent intervention on the left pulmonary artery were compared between patients with and without 22q11 deletion. RESULTS: There were 134 included patients; 19 patients had the deletion (22q11 positive), and 115 patients did not have the deletion (22q11 negative). Tetralogy of Fallot was present in 8/19 and 101/115 patients, truncus arteriosus in 7/19 and 7/115 patients, and interrupted aortic arch in 4/19 and 7/115 patients. Patients who were 22q11 positive had a reduced left pulmonary artery/right pulmonary artery ratio on both the initial echocardiogram [0.88 (interquartile range 0.71, 0.97) versus 1.02 (interquartile range 0.92, 1.12); p < 0.001] and most recent echocardiogram [0.66 (interquartile range 0.62, 0.91) versus 1.01 (interquartile range 0.89, 1.16); p < 0.001] and were more likely to have intervention on the left pulmonary artery at their initial surgery (36% versus 8.7%; p = 0.003). CONCLUSION: Patients who were 22q11 positive trended towards reduced left pulmonary artery/right pulmonary artery ratios and need for early surgical intervention on the left pulmonary artery in comparison to patients without 22q11 deletion negative patients.