A Rare Case of Coronary-Coronary Fistula in Patient with Coarctation of Aorta

Dr. Mavani can be contacted at keyurmavani@gmail.com.

Introduction

A coronary artery fistula is defined as a direct communication between a coronary artery and another vascular structure. Coronary artery fistulas account for 0.2-0.4% of congenital cardiac anomalies¹ and occurs in association with other congenital anomalies in 20-45% of patients^2,3. Coronary artery fistulas usually involve the heart chambers, the pulmonary artery, or cardiac veins. Coronary-coronary fistula is an extremely rare occurrence. Coarctation of the aorta, which forms about 6-8% of congenital heart disease⁴, may be seen alone or in conjunction with other anomalies of the heart and blood vessels. Here, we present a case of coarctation of the aorta, coronary-coronary fistula, and aortic stenosis probably related to a bicuspid aortic valve.

Case

A 62-year-old female with a past medical history of hypertension, hypothyroidism, and known critical aortic stenosis was sent to the emergency department from her primary care physician’s office due to shortness of breath, an inability to get an arm blood pressure reading, and generalized weakness. On admission, the patient was found to be in acute on chronic decompensated systolic diastolic heart failure New York Heart Association (NYHA) Class III. She was diuresed cautiously. An echocardiogram showed moderate left ventricular systolic dysfunction with an ejection fraction of 35%, severe pulmonary hypertension, a critical aortic stenosis with a valve area of 0.4 cm², and moderate-severe mitral regurgitation. Due to heavy calcification, it was difficult to assess on transesophageal echocardiogram whether the aortic valve was bicuspid.

Cardiac catheterization via a femoral approach was unable to be performed due to an inability to pass a wire and catheter through the descending aorta to the arch. Subsequent chest computed tomography showed coarctation of the proximal descending aorta distal to origin of the left subclavian artery (Figure 1). Cardiac catheterization via a radial approach demonstrated normal coronaries, a gradient of 20mm Hg through the coarctation, and a fistula of the distal left circumflex with a connection to the distal right coronary artery (Figures 2-3). The patient was transferred to a tertiary care center for an aortic valve replacement and repair of the aortic coarctation.

Discussion

Congenital heart disease may occur in isolation or in conjunction with other anomalies. A bicuspid aortic valve, although mostly sporadic, may be a congenital disorder and is seen in 1-2% of the general population.⁴ Coarctation of the aorta is associated with a bicuspid aortic valve in 50-80% of cases.⁵ Although rare, a bicuspid aortic valve could be seen in conjunction with a congenital coronary anomaly. Congenital coronary artery fistulas usually involve the right coronary artery. Small fistulas do not cause any hemodynamic compromise, whereas large fistulas can cause coronary steal and ischemia of the segment of the myocardium perfused by the coronary artery. Large coronary artery fistulas do not close spontaneously and may also cause complications such as congestive heart failure, arrhythmias, infective endocarditis, rupture, and death. 

A diagnosis of congenital heart disease may be often overlooked until the adult ages. The diagnosis is then established either on further investigation of incidental findings or based on the patient’s complaints. The presence of additional anomalies should be investigated even in patients when congenital heart disease is found at adult age. Treatment of the congenital heart disease should take into consideration current guidelines and patient preferences. 

References

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2. Fernandes ED, Kadivar H, Hallman GL, Reul GJ, Ott DA, Cooley DA. Congenital malformations of the coronary arteries: the Texas Heart Institute experience. Ann Thorac Surg. 1992;54:732–740.
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5. Tawes RL, Berr CL, Aberdeen E. Congenital bicuspid aortic valve associated with coarctation of the aorta in children. Br Heart J. 1969; 31:132-172.