Neonatal ventricular fibrillation and an elusive ALCAPA: things are not always as they seem.

An anomalous left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital cardiac condition that typically presents with poor feeding and failure to thrive from progressive myocardial ischaemia. Previous reports of ALCAPA presenting with ventricular fibrillation (VF) have suggested a causative relationship. In this case, we present a neonate with VF without apparent cause after an extensive evaluation. Following implantable cardioverter-defibrillator placement for presumed idiopathic VF, at which time she also underwent surgical ligation of a patent ductus arteriosus (PDA), the neonate developed haemodynamic instability that ultimately was found to be due to ALCAPA. Numerous echocardiograms had missed the ALCAPA in the setting of mildly elevated pulmonary artery pressure. We discuss the limitations of current ultrasound technology in diagnosing ALCAPA in the setting of pulmonary hypertension and explain why the relationship between this patient's diagnosis of ALCAPA and her episode of VF is not clearly causative.