Coronary Artery Fistulae: 4 cases repaired surgically

Malta Medical Journal Volume 27 Issue 01 2015 Abstract Coronary artery fistulae involve a communication between a coronary artery and a heart chamber or part of the pulmonary circulation. Most are asymptomatic and discovered incidentally, whilst larger ones may cause coronary steal syndrome. Fistulae may produce continuous murmurs and are diagnosed at echocardiography or angiography. Treatment is by percutaneous coil embolisation or open surgery. We review four cases treated with surgical closure. All patients were asymptomatic and diagnosed incidentally at angiography. One case involved a failed attempt at percutaneous coil embolization requiring immediate open surgery. The other three cases required other operative procedures and the fistulae were oversutured during the same procedure. Introduction Coronary artery fistulae, although rare, are amongst the commonest congenital cardiac anomalies. They involve a communication between a coronary artery and a heart chamber or part of the pulmonary circulation. Most are asymptomatic and discovered incidentally. Larger ones may cause coronary steal syndrome, as blood is shunted from the coronary artery to the ventricle or pulmonary circulation, bypassing the myocardium, and causing symptoms of angina, arrhythmias or highoutput heart failure. First described in 1908 by Maude Abbott, fistulae can be classified as a congenital abnormality of termination . Embryologically coronary artery fistulae are thought to arise as a persistence of sinusoidal connections between the lumens of the primitive tubular heart that supply myocardial blood flow in the early embryologic period. Most coronary artery fistulae arise from the right coronary artery (40-60%) and those arising from the left coronary artery are predominantly from the left anterior descending artery. The right atrium or ventricle and pulmonary artery are the site of termination in 90% of cases. Small fistulae may remain clinically silent and are recognized at routine angiography, echocardiography or autopsy. In small fistulae, the myocardial blood supply is not sufficiently compromised to cause symptoms. Although spontaneous closure usually occurs, some can dilate over time. The increased flow in the feeding artery may result in dilatation resulting in the commonly associated finding of coronary aneurysms. Fistulae may give rise to various complications, the commonest being myocardial ischaemia, including ischaemic cardiomyopathy, papillary muscle rupture from chronic ischaemia and congestive cardiac failure from volume overload. Older patients may present with signs of congestive heart failure, arrhythmias, syncope or chest pain. Bacterial endocarditis and sudden cardiac death have also been described . Rare cases are described of multiple microfistulae causing angina. The management of such fistulae is with antianginal medication and risk factor control. However these reports are rare and no evidence based management is offered in the literature .