A rare etiology for pulmonary artery dissection: Multiple coronary to pulmonary artery fistulas.

A 53-year-old male patient with hypertension presented to our hospital with frequent chest pain and shortness of breath for several days. Chest x-ray showed normal heart size without pulmonary edema. Electrocardiography showed atrial fibrillation with a moderate ventricular response without evidence of ST segment elevation. Echocardiography demonstrated moderate mitral regurgitation and impaired left ventricular function. Mitral regurgitation can be classified as type IIIb of the Carpentier classification, and his impaired left ventricular function may be caused by ischemic heart disease. During the coronary angiography, it was observed that there was a subtotal occlusion in the right coronary artery, a 75% stenosis in the middle left circumflex artery, and a total occlusion in the proximal left anterior descending artery. In addition, three fistulas were detected: a large fistula originating from the orifice of the right coronary artery, a small fistula originating from the left main coronary artery, and another small fistula arising from the proximal left anterior descending artery. All fistulas drained into the main pulmonary artery (Figure 1A,B, white arrow). During the right heart catheterization, a filling defect was found in the main pulmonary artery, and pressures of 49/26 and 42/21 mmHg were recorded for the main and right pulmonary arteries, respectively. Oxygen saturation levels were also measured, with readings of 66.2% for the right ventricle, 69.3% for the main pulmonary artery, and 68.3% for the right pulmonary artery. Contrast enhanced computed tomography scan showed pulmonary artery dissection at main pulmonary artery (Figure 1C, black arrowhead). Additionally, a fistula draining into the false lumen was observed (Figure 1C, white arrow). The patient underwent coronary artery bypass surgery, fistula ligation, and excision of a dissecting flap. During gross examination, a false lumen was identified on the left lateral aspect of the main pulmonary artery, beginning just above the pulmonary valve. All of the coronary fistulas drained into the false lumen (Figure 1D). Pathological examination revealed focal myxomatous changes in the intimal flap. The patient was discharged without any complications, and a follow-up computed tomography scan conducted 10 years