The Current Status of Coronary Artery Fistula

Abstract

Coronary artery fistula (CAF) is an unusual coronary anomaly. Most coronary artery fistulas are congenital, but the incidence of acquired CAFs is increasing following the incremental use of intravascular procedures and interventional techniques. The prevalence of CAF is about 0.1-0.8% based on coronary angiography or echocardiography studies. CAFs originate mostly from the right coronary artery and the left anterior descending artery and have proximal involvement. Most of them drain into the right atrium, right ventricle and pulmonary artery. Few of them drain into the left ventricle or left atrium. According to the site of drainage, CAFs have varied physiologic presentations. Clinically, about half of patients with a CAF are asymptomatic. Large fistulas can induce congestive heart failure, angina, myocardial infarction, arrhythmia or pulmonary hypertension. Endocarditis, coronary artery rupture and sudden cardiac death have also been reported. Physical examination usually reveals a continuous murmur. Myocardial ischemia with abnormal 201Tl perfusion image can be detected in large portion of patients with CAF. Coronary angiography is the major diagnostic tool. Cardiac echocardiography, magnetic resonance imaging and multidetector computed tomography are also used for diagnosis. Treatment includes medical therapy, transcatheter closure of the fistula or surgical ligation of the fistula. However, these treatments should be tailored according to the size and location of fistula, and the patient's age and clinical presentation. The characteristics of CAFs in Oriental people were also discussed in this article.