Coronary artery fistulae (CAF) are rare anomalies. Left anterior descending(LAD) to Pulmonary artery (PA) CAF, represent a minority of cases. Large fistulas, create a significant shunt and a “steal phenomenon”, and can lead to myocardial ischemia and heart failure (HF) if left untreated.
We present a 57 years old female with a large LAD to PA fistulae. Given the rare occurrence and the predominance of low shunt of LAD to PA CAF, this case is functionally exceptional in this fistulae variant, causing a significant shunt which resulted in daily cardiac ischemic chest pain. Diagnosis work up included a nuclear stress test, Coronary Angiography and 3-D Coronary Computed Tomography Angiogram (CCTA). Traditionally, surgery has been the main therapy for symptomatic CAF, but transcatheter closure has emerged as a less invasive strategy and is a valuable alternative or even preferable if no associated cardiac conditions are present, provided the anatomical characteristics of the fistulae are appropriate. The surgical approach includes off pump epicardial interruption of the fistula or closure through a cardiac chamber (trans-cameral) or transpulmonary, or epicardial closure using Cardiopulmonary bypass. Caution must be taken in cases of CAF with Coronary Artery (CA) aneurysm in dominant CA, or drainage into the Coronary Sinus, as the possibility of ischemic complications are higher. Due to anatomical considerations and tortuosity of the fistulae, our patient was considered not amenable for percutaneous closure and surgery was opted. Epicardial closure of the fistula was performed on a beating heart, off pump. Outcome was favorable with complete resolution of ischemic symptoms.
Symptomatic, high shunt CAF must be interrupted. The presence of daily ischemic symptoms in our case report patient, is worth to be remarked. Alternatives for fistulae closure are transcatheter or surgery, depending on anatomic variables and the presence of associated cardiac conditions. Surgical epicardial closure of LAD to PA fistulae variant can be done with very low mortality and morbidity, but other variants with coronary aneurysm, drainage in the coronary sinus or other concomitant cardiac defects, may result in ischemic complications and higher perioperative mortality and worse long- term outcome.