We found a digenic likely pathogenic variant (ABCC8/ SMAD 1) in a case of coincidental PAH and several thoracic collaterals, a pathogenic variant in BMPR2 in a case of PAH after defect closure, and a pathogenic SOX17 variant in a patient with Eisenmenger syndrome. The gene discussed is ABCC8; the disease is pulmonary arterial hypertension.