Coronary cameral fistula with left main coronary artery aneurysm: A challenging case
Devvrat Desai, Jignesh Kothari
Department of Cardiovascular and Thoracic Surgery, U. N. Mehta Institute of Cardiology and Research Center (Affiliated to B. J. Medical College), Civil Hospital Campus, Ahmedabad, Gujarat, India
Correspondence Address:
Jignesh Kothari
Department of Cardiovascular and Thoracic Surgery, U. N. Mehta Institute of Cardiology and Research Center (Affiliated to B. J. Medical College), Civil Hospital Campus, Asarwa, Ahmedabad - 380 016, Gujarat
India
Source of Support: None, Conflict of Interest: None
CheckDOI: 10.4103/jpcs.jpcs_54_22
Coronary fistulae with cardiac chambers (cameral fistulae) are rare congenital vascular anomalies. Here, we are reporting a case of a 25-year-old male patient who presented with a history of palpitation and chest pain. He was evaluated further and on cardiac multi-slice computed tomography, he was diagnosed to have an extremely rare coronary cameral fistula arising from the left main coronary artery, traversing tortuously between aortic roots anteriorly and left atrium posteriorly, and culminating into superior vena cava just before the cavoatrial junction. Intraoperative complexity was encountered due to the presence of a large left main coronary aneurysm and aneurysmally dilated superior vena cava. Elective surgery was performed on cardiopulmonary bypass with aortic and bicaval (high superior vena cava) cannulation. Cardioplegia delivery was challenging due to the presence of a large fistulous connection between the aortic root and superior vena cava. The patient was operated on successfully for coronary cameral fistula and symptoms resolved.
Keywords: Coronary cameral fistula, left main coronary aneurysm, left main coronary artery, machinery murmur, palpable thrill
A coronary artery fistula is an abnormal communication between one of the coronary arteries and a cardiac chamber or vein. Coronary fistulae with the cardiac chambers (cameral fistulae) are rare congenital vascular anomalies. Most commonly coronary fistulae arise from the right coronary artery (60%). Ninety percentage of the fistulae communicate the right side of the heart.[1] The most frequent sites of communication are the right ventricle, right atrium, coronary sinus, and pulmonary vasculature. This type of abnormal fistulous connection between a left main coronary artery and the superior vena cava is an extremely rare condition. The estimated prevalence of coronary cameral fistula in association with the left main coronary artery aneurysm is extremely low (0.02).[2] The majority of these patients with coronary cameral fistulae remain asymptomatic and present in adulthood, often being diagnosed accidentally.
Here, we are reporting a case of a 25-year-old male patient who presented with a history of palpitation and chest pain. He was evaluated further and on cardiac multi-slice computed tomography (MSCT), he was diagnosed to have an extremely rare coronary cameral fistula arising from the left main coronary artery.
Case ReportA 25-year-old male presented with a history of palpitation even at rest and chest pain for the past few years. On clinical examination, the patient had a regular heart rate of 80/min with a blood pressure of 130/22 mm of mercury (mmHg). Palpation revealed a palpable thrill on the precordium. All peripheral signs of aortic regurgitation were present. Distal pulses were recorded in all four limbs. On auscultation, a loud second heart sound and continuous machinery murmur in the precordium were present.
Diagnosis and imaging
The electrocardiogram (ECG) showed no significant changes. The chest radiograph revealed cardiomegaly with mediastinal widening [Figure 1]. Transthoracic echocardiography revealed a large coronary cameral fistula arising from the left main coronary artery and traversing tortuously along the posterior aortic root and roof of the left atrium and opening into superior vena cava just above the cavoatrial junction with continuous left-to-right (L-R) shunt. All chambers were volume overloaded with right-sided chamber enlargement (right > left). Moderate aortic regurgitation was found on the color Doppler study due to prolapse of left and noncoronary cusps.
Figure 1: Chest radiograph revealed cardiomegaly with mediastinal widening suggestive of dilated SVC and right atrium. SVC: Superior vena cavaCardiac MSCT revealed dilated fistulous tract measuring 23.6 mm in diameter arising from the left main coronary artery. It traverses tortuously between the aortic root anteriorly and the left atrium posteriorly. The fistulous tract is dilated at the terminal end before culminating into the superior vena cava just above the cavoatrial junction. The coronary arteries' anatomy appeared normal [Figure 2]a, [Figure 2]b, [Figure 2]c.
Figure 2: (a) Aneurysmally dilated SVC, (b) tortuous fistula arising from aneurysmally dilated, (c) Fistula tract traverses tortuously posterior to aortic root and culminating into an aneurysmally dilated SVC. SVC: Superior vena cava, AO: Aorta, MPA: Main pulmonary artery, LMCA: Left main coronary arteryProcedure
He was scheduled to undergo surgical closure of the coronary cameral fistula. The patient was prepared under general anesthesia using standard protocols. Endotracheal intubation was performed, and a transesophageal echocardiography (TEE) probe was placed. Intraoperative TEE revealed a fistulous tract, aneurysmal sac, and its communications. The left main coronary artery was aneurysmally dilated and the flow velocity in the left main and the fistula was found to increase on pulse Doppler.
It was continuous and compatible with an L-R shunt. Color Doppler revealed turbulence in the fistula and the opening in the superior vena cava just above the cavoatrial junction [Figure 3]a and [Figure 3]b. Moderate aortic regurgitation was found on the color Doppler study due to prolapse of left and noncoronary cusps. Dilated left the main coronary was abutting both aortic cusps.
Figure 3: (a) Intraoperative TEE revealed a fistulous tract, aneurysmal sac and its communications, (b) Color Doppler revealed turbulence in the fistula and the opening in the superior vena cava just above the cavoatrial junction. TEE: Transesophageal echocardiographyThe proximal end of the coronary cameral fistula is identified in the floor of the aneurysmal left main coronary artery which was closed similarly in two layers and reinforced with pledget interrupted sutures in such a way that the floor of the aneurysm is approximated with roof and aneurysm gets collapsed [Figure 4]a, [Figure 4]b, [Figure 4]c, [Figure 4]d Both left coronary ostia were secured to prevent any damage or kinks. The left main coronary artery aneurysm was abutting against the left and noncoronary cusps. The aortic valve was checked for competency and found to be satisfactory [Figure 5].
Figure 4: (a) Proximal and distal opening of the fistulous tract is confirmed after passing silk thread across the tract, (b) Tortuous fistula tract can be seen originating from the left main coronary artery passing posterior to root reaching on the left atrial roof and culminating into the superior vena cava just above the cavoatrial junction depicted by the yellow line, (c) Caval end of fistula closed in two layers using prolene suture, (d) Aortic end of fistula after closure with prolene sutures in two layersFigure 5: Postoperative TEE revealed no flow turbulence in the fistula tract and trivial aortic regurgitation. TEE: Transesophageal echocardiographyThe postoperative course was uneventful with the disappearance of symptoms and the heart murmur [Figure 6].
Figure 6: (a) Reduction in left main artery aneurysm post repair, (b) No residual shunt or fistula as tract can be seen completely thrombosed, (c) Reconstructed image showing the closure of fistula tract with no residual shunt. LMCA: Left main coronary artery DiscussionPathophysiologically, coronary fistula causes myocardial stealing in myocardial blood flow. In compensation, the coronary artery progressively gets dilated. This explains the aneurysmal malformation of the left main coronary artery in the present case. The coronary cameral fistula may progress to frank aneurysm, intimal ulceration and rupture, atherosclerotic deposition, calcification, and mural thrombosis.
Embryologically, it describes the persistence of sinusoidal connection between the lumen of the primitive tubular heart.[3] It also occurs in 45%–50% of patients with pulmonary atresia with an intact ventricular septum. Their morphogenesis is thought to begin early in their development.[4]
Congenital coronary artery fistula proximal to a segment of acquired atherosclerotic stenosis aggravates the distal perfusion deficit by acting as a low-resistance alternative to the zone of coronary artery stenosis.[5]
The anesthetic management of coronary cameral fistula aims to prevent a coronary steal and perioperative myocardial ischemia. These can be avoided by decreasing the left-to-right shunt. Hence, drugs that increase systemic vascular resistance or decrease pulmonary vascular resistance should be used very cautiously. Intraoperative ECG monitoring is a very useful tool to prevent perioperative ischemia. TEE helps to determine the new onset of regional wall motion abnormalities.
Adequate myocardial perfusion with the fistula is very important during cardiopulmonary bypass. Hence, we believe in providing ostial antegrade cardioplegia under vision.
Complications[6] related to coronary cameral fistula are more common in the adult group (35%) than in the younger group (11%). Surgical complications of fistula repair are also reported worldwide which include myocardial ischemia requiring coronary bypass graft (3%), residual fistula, and recurrence (4%).
Cardiac catheterization[7] is another therapeutic option available which includes coils or other devices. Contraindications for the transcatheter approach include fistulae with multiple connections, tortuous routes, and acute angulations that make catheter positioning difficult or impossible. In our patient, the percutaneous approach was not considered because of the left main artery aneurysm with a tortuous fistula.
Spontaneous closure[8] occurs in 23% of small fistulae, primarily those arising from the left coronary system. Conservative management can be appropriate in some patients with small and asymptomatic coronary cameral fistulae. Large fistulae usually demand intervention as they present with symptoms. Operative strategy solely depends on the morphology of the fistulous connection and the time of presentation. Hence, it varies with individuals.
Ipek et al.[9] and Ahmad et al.[10] described giant right coronary artery (RCA) aneurysms and fistulae opening, respectively, into the right ventricle and the right atrium. Tada et al.[11] described an RCA aneurysm associated with a superior vena cava fistula. In that case, the fistula was ligated without aneurysmorrhaphy.
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The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understands that his name and initials will not be published and due efforts will be made to conceal his identity, but anonymity cannot be guaranteed.
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Conflicts of interest
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