Patient, male, 33 years old, with a history of dyspnea on exertion for more than 10 years and chest pain for one month. Physical examination: Blood pressure 151/57 mmHg, heart rate 87 beats per minute, irregular rhythm, a Grade III/VI systolic murmur heard in the precordium. Electrocardiogram showed fragmented QRS complexes in the inferior leads and clockwise rotation.
Upon admission, the initial transthoracic echocardiogram (TTE) and transesophageal echocardiogram (TEE) revealed left ventricular enlargement, diffuse aneurysmal dilatation of the right coronary artery (RCA) with a maximum diameter of approximately 38 mm. A fistula with a diameter of about 10 mm was observed in the basal segment of the left ventricular inferior wall, connecting to the aneurysmal RCA. Color Doppler flow imaging (CDFI) demonstrated a significant diastolic multicolored flow jet originating from the fistula, with a velocity of 2.1 m/s and a pressure gradient of 18 mmHg. The ejection fraction (EF) was measured at 65%(Fig.1). The ultrasound diagnosis suggested right coronary artery aneurysm with right coronary artery-to-left ventricle fistula (RCALVF).
Fig.1
Figures A,B,C are pictures of TTE, revealed left ventricular enlargement, dilatation of RCA, CDFI demonstrated jet originating from the fistula with a velocity of 2.1 m/s; Figure D,E,F are TEE pictures, showed clearer visualization of the entire expansion of the RCA, as well as the size and border of the fistulae.
Coronary angiography revealed a normal origin of the coronary arteries, with a dominant RCA. The left anterior descending artery (LAD) and left circumflex artery (LCX) appeared normal(Fig.2). However, the RCA exhibited abnormal development with a distal ventricular fistula. Cardiac CT angiography (CTA) confirmed the presence of a right coronary artery aneurysm and RCALVF, with no collateral circulation in the RCA(Fig.3).
Fig.2
Coronary angiography revealed a normal origin of the coronary arteries, with a dominant RCA. The left anterior descending artery (LAD) and left circumflex artery (LCX) appeared normal.
Fig.3
Cardiac CT angiography (CTA) confirmed the presence of a right coronary artery aneurysm and RCALVF, with no collateral circulation in the RCA. Three-dimensional reconstruction provides a more intuitive and complete picture of the tortuous course of the RCA.
On October 24, 2023, the patient underwent a repair procedure for the coronary artery fistula (CAF). Intraoperatively, the right coronary artery was significantly aneurysmal and occupied the atrioventricular groove. The right coronary artery orifice was dilated to approximately 10 mm, and there was a communication between the right coronary artery and the left ventricular cavity. The fistula opening was located just below the midpoint of the posterior mitral valve leaflet and measured approximately 12×10 mm, with some surrounding calcification. After exploring the right coronary artery wall, no branches were found, and the fistula opening was exposed. A patch was used for continuous suturing to close the left ventricular side of the fistula(Fig.4). Immediate postoperative TEE showed sluggish blood flow within the dilated right coronary artery, with evidence of thrombus formation. On the first day after the surgery, a bedside TTE revealed no abnormal shunt signals within the left ventricle(Fig.5), and the EF was measured at 61%. The patient had an uneventful postoperative course and was discharged ten days later[1,2].
Fig.4
Intraoperatively, the right coronary artery was significantly aneurysmal(White arrow on the left), and there was a communication between the right coronary artery and the left ventricular cavity(White arrow on the right).
Fig.5
Immediate postoperative TEE showed sluggish blood flow within the dilated right coronary artery, with evidence of thrombus formation(A,B). CTA one week postoperatively showed that the fistula had closed and no blood flow was seen in the RCA(C,D).