Coronary Artery Fistulas: A Review of the Current and Future Roles of Imaging

Outcomes of Transcatheter Closure of Congenital Left Circumflex Coronary Artery Fistula

BACKGROUND

Congenital left circumflex coronary artery fistula (LCX-CAF) is a relatively rare type of coronary artery fistula (CAF); little is known about the outcomes of transcatheter closure (TCC) of LCX-CAF.

METHODS AND RESULTS

All consecutive patients admitted to Fuwai Hospital and scheduled for TCC of LCX-CAF between January 2012 and December 2022 were reviewed retrospectively. Of the 25 consecutive patients (mean [±SD] age 34±20 years; 48% male) admitted and scheduled for TCC of congenital LCX-CAF, the procedure was feasible in 22 (77.3%). The mean (±SD) diameter of the fistulas was 6.99±2.04 mm; 21 (84%) patients had a large fistula (i.e., diameter >2-fold greater than non-feeding coronary artery). Occluders were deployed via a transarterial approach and arteriovenous loop in 6 (27.3%) and 16 (72.7%) patients, respectively. No procedural complications were recorded. Although the procedural success rates are similar for single LCX-CAF and left anterior descending CAF (81.25% vs. 92.86%; P=0.602), the mean time from initial angiography to first occluder deployment is significantly longer for LCX-CAF (83.06±36.07 vs. 36.00±9.49 min; P<0.001). The mean (±SD) follow-up time was 62.2±45.5 months. The incidence of myocardial infarction and recanalization of the fistula was 4.5% (1/22) and 9.1% (2/22), respectively.

CONCLUSIONS

TCC of LCX-CAF is a feasible and effective alternative to surgical repair, with comparable outcomes in selected patients. Optimal medical therapy to prevent post-closure myocardial infarction requires further investigation.

Transcatheter closure of multiple coronary artery fistulas: a coronary computed tomography angiography-based anatomic classification

INTRODUCTION AND OBJECTIVES

This study aimed to retrospectively analyze the anatomical characteristics and classification of multiple coronary artery fistulas (MCAFs), and to compare the outcomes of transcatheter closure between MCAFs and single fistulas.

METHODS

All patients who underwent attempts at transcatheter closure of coronary artery fistulas (CAFs) at Fuwai Hospital from 2010 to 2023 were retrospectively reviewed. Patients were categorized into single fistula and MCAFs groups, and anatomical characteristics and transcatheter closure outcomes were compared between the 2 groups.

RESULTS

This retrospective study included 146 patients who underwent attempted transcatheter closure of CAFs, with a 14.38% failure rate. Among the 146 patients with CAFs, 32.19% were identified as having MCAFs, with types I, II, and III constituting 40.43%, 42.55%, and 17.02%, respectively. Unlike single fistulas, which predominantly originated from the right coronary artery and terminated in the left ventricle, MCAFs mainly had simultaneous origins from the right coronary artery and left anterior descending artery (29.79%), and predominantly drained into the pulmonary artery (70.21%), with a notable prevalence of plexus-like morphology (38.3% vs 2.02%, P<.001). The success rate of transcatheter closure was significantly lower for multiple fistulas compared with single fistula (64.29% vs 84.34%, P=.011). Multivariate regression analysis indicated that the risk of closure failure for MCAFs was 2.64 times that of single fistulas.

CONCLUSIONS

MCAFs are common among CAFs and can be classified into 3 types based on the number and location of their origins and terminations. The risk of failure of transcatheter closure is significantly higher in MCAFs than in single fistulas.

A successful surgical management for a thrombosed giant left coronary aneurysm with right ventricular fistula in a young patient

Giant coronary aneurysm with ventricular fistula is rare. Due to the limited data from randomised clinical trials, therapeutic strategies for coronary aneurysms predominantly rely on on case series and anecdotal evidences. Reporting cases that provide practical experience in managing these aneurysms is therefore crucial. In this article, we report a rare case of a successful surgical management for a thrombosed giant left coronary aneurysm with right ventricular fistula, which is larger than any previously reported cases.

Coronary artery fistula with or without aneurysm: A large comparative study

Background

The knowledge of coronary artery fistula (CAF) with coronary aneurysm mostly comes from case reports and is very limited. However, the management of CAF with and without aneurysm is different, more understanding of its clinical and imaging features is necessary. This is the first research focus on it through a large comparative study.

Purpose

To investigate the differences in imaging and clinical features of CAF with and without aneurysms.

Methods

We reviewed 96,037 consecutive patients undergoing coronary computed tomography angiogram (CCTA) between 2016 and 2020 and total of 429 CAF adult patients were enrolled. Those patients were divided into the CAF with aneurysm group (321 cases, 74.83%) and CAF without aneurysm group (108 cases, 25.17%) according to whether complicated with coronary aneurysm. Clinical baseline data, electrocardiographic (ECG) characteristics, the presence or absence of coronary atherosclerosis, complication symptoms and fistulous origin, entry site, number and diameter were analyzed. Chi-square test, T-test, Mann-Whitney U tests, and logistic regression analysis were performed.

Results

Most of the clinical baseline data did not differ significantly between the two groups (P > 0.05). However, heart murmur, coronary atherosclerosis, infective endocarditis (IE), fistulous diameter and fistulous entry site were significantly different (P＜0.05). Further multivariate logistic regression analysis showed that large fistulous diameter and coronary-cardiac chamber arterial fistulas was dependent risk factors for CAF complicated with aneurysm.

Conclusion

CAF patients with aneurysm were more prone to develop heart murmur than those patients without aneurysm. Different from other sites of aneurysms, coronary atherosclerosis is more common in CAF without aneurysm. Larger fistulous diameter and coronary-cardiac chamber arterial fistula are dependent risk factors for CAF with aneurysms.

Diagnosis of left anterior descending branch-right ventricular fistula with giant coronary artery aneurysm by contrast echocardiography: A case report

BACKGROUND

Coronary fistulae are communications between a coronary artery and a heart chamber or vessel. The final diagnosis is usually made by coronary angiography or computed tomographic (CT) angiography. Here we report a case by employing contrast echocardiography in diagnosis of a giant coronary aneurysm with right ventricle (RV) fistula.

CASE PRESENTATION

The patient, a 29-year-old woman, referred to our institution with a complaint of palpitation occasionally. Transthoracic echocardiogram showed a spherical, echogenic structure in the apex of RV. Proximal to the aneurysm, the left anterior descending branch (LAD) remained enlarged (8-9 mm) and showed a fistulous communication with the echogenic structure. A contrast echocardiography was performed, and 4-5 cardiac cycle after the left ventricle was enhanced, the echogenic structure started to become more prominent and several fistulae were seen between RV and the echogenic structure. Computed tomography (CT) angiography and coronary angiography confirmed the dilation (9 mm in diameter) of the LAD with an aneurysm at the distal segment of the LAD, with a small amount of iodinated contrast agent flowing into the subsequent region of the RV, thereby characterizing a LAD-to-RV fistula.

CONCLUSION

The final diagnosis of fistula is usually made by coronary angiography or CT angiography. However, contrast echocardiography is also a well-established method for the demonstration of intracardiac shunting. In this case, the contrast echocardiography clearly revealed one of the fistulae between the aneurysm and RV.