[A successful surgical treatment for huge left circumflex artery-right ventricle fistula using the fistula occlusion test].

A surgical case of rare coronary artery fistula between the left circumflex artery and right ventricle was reported. A 46-year-old woman had suffered from exertional dyspnea and palpitation for three years. Pan systolic heart murmur was heard through the left 4th inter costal space. The chest X-ray film demonstrated cardiac enlargement and lung congestion, and the electrocardiograms showed atrial fibrillation and left ventricular hypertrophy when she was admitted to our hospital. Preoperative catheterization revealed a huge coronary artery fistula originating from the left circumflex artery and opening into the right ventricle through the posterior wall of the heart. The left-to-right shunt ratio was 60% and Qp/Qs was 2.47. At operation, the dilated circumflex artery fistula was carefully dissected and the tape was passed around the fistula as a tourniquet under extra corporeal circulation on the beating heart. To estimate myocardial ischemia, the fistula occlusion test was performed by tightening the previously placed tourniquet. Monitoring of electrocardiograms, transesophageal echocardiography, and hemodynamics were useful to detect myocardial ischemia. The occlusion test was performed under ECC for 5 minutes. No ischemic changes were observed. The fistula was interrupted under cardiac arrest at the point of the occlusion test.