What other anomalies? Failure to wean post ventricular septal defect repair secondary to anomalous origin of the left coronary artery from the pulmonary artery

Summary A six week old infant underwent ventricular septal defect and atrial septal defect closure. Preoperative echocardiography showed evidence of pulmonary hypertension. The post operative course was complicated failure to wean from ventilatory and inotropic support. Echocardiography showed severe left ventricular (LV) dysfunction and suggested some fistulous drainage of the left coronary artery into the right pulmonary artery; this anomalous drainage of the left coronary artery into the right pulmonary artery (ALCAPA) was confirmed with coronary angiogram. Re-implantation of the left coronary artery into the aorta was performed. Extra-corporeal membrane oxygenation (ECMO) was required to allow time for ventricular recovery. Supports were weaned gradually, with concurrent evidence of LV recovery and the child was discharged on postoperative day 30. ALCAPA is rare and typically presents at 8 weeks of age with symptoms of heart failure, as pulmonary pressure falls leading to myocardial ischaemia due to myocardial hypoperfusion with relatively desaturated blood. In our case the pulmonary hypertension and left to right shunt preoperatively were protective, maintaining forward flow of relatively oxygenated blood. While protective to the myocardium this made the preoperative diagnosis of ALCAPA difficult, as there was no flow reversal on Doppler echocardiography. Closure of the septal defects meant this protective effect was lost, with subsequent severe myocardial ischaemia and heart failure. This case highlights the diagnostic challenges of ALCAPA, the ‘protective’ effects of pulmonary hypertension with ALCAPA, and the importance of early cardiac catheterization in the setting of unexplained failure to wean post cardiac surgery.