A Case Report of Coronary Cameral Fistula with Rare Communication Sites

Abbreviations

CAFs, Coronary artery fistulas

CCFs, Coronary cameral fistulas

CT, Computed tomography

LAD, Left anterior descending artery

MRI, Magnetic resonance imaging

TTE, Transthoracic echocardiography

INTRODUCTION

Coronary cameral fistulas (CCFs) are rare cardiac anomalies defined as communications between a coronary artery and a cardiac chamber.¹ The origin and termination sites vary, and could be diagnosed via non-invasive tools.² The right coronary artery is the most common origin site, while the left circumflex artery is the least.³ Despite most CCFs are asymptomatic and diagnosed accidently, some patients presented with fatigue, dyspnea, angina, endocarditis or heart failure.^4,5

We present a patient with CCF, which has rare communication sites, detected by transthoracic echocardiography (TTE).

CASE PRESENTATION

This is a 44-year-old male with history of gout and is a heavy smoker. He presented to our institution due to palpitation at night without dyspnea, chest pain or syncope. Physical examination showed grade III/VI diastolic murmur over left sternal border and grade I/VI systolic murmur over apex. Transthoracic echocardiography (TTE) revealed abnormal diastolic flow over base of mitral annulus, suspecting coronary artery fistula (Figure 1). Coronary angiography performed for further investigation revealed dilated coronary fistula drainage from the left anterior descending artery (LAD) to the left ventricle posterior lateral mitral sub-valvular region (Figure 2).

Figure 1.

Transthoracic echocardiogram showed a color Doppler jet flow of coronary fistula to the left ventricle. (A) Apical 3 chamber view: the arrow indicates a jet from the basal inferolateral wall to the left ventricle. (B) Apical 4 chamber view: the arrow indicates a jet from the basal inferolateral wall to the left ventricle. (C) Continuous Wave Doppler showed a jet in the diastolic phase. (D) Short-axis view: the arrow indicates a jet from the inferior wall to the left ventricle.

Figure 2.

Coronary angiography showed aneurysmal changed left anterior descending artery drainaged to the left ventricle. (A) RAO/Caudal view. (B) LAO/Caudal view. (C) RAO view. LAO, left anterior oblique; RAO, craniocaudal right anterior oblique view.

Given the huge size of the fistula, catheterized occlusion by coil or gelfoam was not indicated. Surgical intervention could be considered, however, after discussing with the cardiovascular surgeons, the patient refused surgical intervention at this point due to no critical symptoms. Out-patient department follow-up was recommended.

DISCUSSION

Coronary angiography remains the gold standard for diagnosis, while non-invasive examination including echography, magnetic resonance imaging (MRI) and computed tomography (CT) becoming more important. Dilated vessel and turbulent flow may present via TTE and precise location could be identified via transesophageal echocardiography.⁴

Symptomatic coronary artery fistulas (CAFs) need surgical intervention, while asymptomatic CAFs remain controversial.⁶ Catheter-based intervention becomes a therapeutic choice in this era. Occlusion devices include coils, detachable balloons, double umbrella devices and Amplatzer duct occluders.⁴ However, surgical closure remains the standard treatment.

In our case, we presented a patient with mild symptoms whose fistula was firstly detected via TTE. Coronary angiography revealed rare communication, originating from the LAD and terminating into the left ventricle. A dilated and aneurysmal LAD was diagnosed by the coronary angiography and high pressure gradient was measured by TTE. Due to the huge size of the fistula, catheter-based intervention was not appropriate for him. The sub-valvular location would also be difficult using surgical approach. Considering of the patient’s slight discomfort, invasive intervention was not performed at this time and the fistula would be regularly follow-up at the out-patient department.

LEARNING POINT

This case underscores the importance of considering CCF as a potential diagnosis in patients presenting with cardiac murmurs or symptoms such as palpitations, even in the absence of classic symptoms like dyspnea or chest pain. TTE serves as a crucial non-invasive tool for initial detection, allowing for the identification of abnormal diastolic flow patterns indicative of CCF.

Furthermore, comprehensive imaging modalities, including coronary angiography, CT, and MRI, play a crucial role in confirming the diagnosis and delineating the anatomy of the fistula. While coronary angiography remains the gold standard for diagnosis, TTE provides valuable information, particularly in identifying the presence and general location of the fistula, guiding further diagnostic and management decisions.

Regular outpatient follow-up is essential for monitoring disease progression, emphasizing the importance of a multidisciplinary approach involving cardiologists, cardiovascular surgeons, and the patient in the management of CCF.

DECLARATION OF CONFLICT OF INTEREST

All the authors declare no conflict of interest.