Coronary artery fistula; coronary computed topography – The diagnostic modality of choice

Journal of Cardiothoracic Surgery BioMed Central Open Access Case report Coronary artery fistula; coronary computed topography – The diagnostic modality of choice SA Early*1, TB Meany3, HM Fenlon2 and J Hurley1 Address: 1Department of Cardiothoracic Surgery, Mater Misericordiae University Hospital and Mater Private Hospital, Dublin, Ireland, 2Department of Radiology, Mater Misericordiae University Hospital and Mater Private Hospital, Dublin, Ireland and 3Department of Cardiology, Limerick Regional Hospital, Limerick, Ireland Email: SA Early* - ; TB Meany - ; HM Fenlon - ; J Hurley - * Corresponding author Published: 5 July 2008 Journal of Cardiothoracic Surgery 2008, 3:41 doi:10.1186/1749-8090-3-41 Received: 30 May 2008 Accepted: 5 July 2008 This article is available from: http://www.cardiothoracicsurgery.org/content/3/1/41 © 2008 Early et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Abstract Coronary artery fistulae (CAF) are rare anomalies. They are vascular communications between the coronary arteries and other cardiac structures, either cardiac chambers or great vessels. There can be considerable variation in the course of a coronary artery fistula. We report a case of a coronary artery fistula between the left circumflex coronary artery and the right and left atria. CAF are often diagnosed by coronary angiogram, however with the advent of new technologies such as Coronary Computed Tomography Angiography (Coronary CTA) the course and communications of these fistulae can be delineated non-invasively and with greater accuracy. Clinical summary A 38-year-old woman presented with a 20-year history of chest pain and palpitations. Her past medical history was unremarkable. Clinical examination revealed a pansystolic murmur. A coronary angiogram was performed which identified a large fistula originating from the left circumflex coronary artery draining to the pulmonary artery. There was no evidence of any coronary artery disease. ECG, Echocardiography and Carotid Doppler's were normal. She subsequently underwent an ECG-gated contrastenhanced coronary CT angiography study using a dualtube 128 slice multidetector CT (Siemens, Erlangen Germany). This demonstrated a large fistula between the left circumflex artery and both the posterior aspect of the upper right atrium and the anterior wall of the left atrium. The patient underwent surgical intervention. A median sternotomy was carried out and complete cardiopulmonary bypass was performed. Cardiac arrest was induced with cold crystalloid cardioplegia. The fistula was identi- fied at the origin of the left circumflex artery running along the dome of the left atrium draining through the medial wall of the right atrium. There was also a small communication between the fistula and the left atrium. The fistula was traced back to its origin, at beginning of the circumflex artery where it was closed directly. The distal communications were also closed directly in both the right and left atria. The patient's postoperative course was uneventful and she was discharged home on the 10th postoperative day. Her condition remains stable three months after the operation. Discussion Coronary artery fistulae are uncommon vascular communications between the coronary arteries and other cardiac structures. There are a limited number of cases described in the literature. It is reported that 0.1%–0.2% of all patients who undergo selective coronary angiography are diagnosed with a CAF[1]. CAF most commonly involve the right coronary artery (60%) but can involve both corPage 1 of 3 (page number not for citation purposes) Journal of Cardiothoracic Surgery 2008, 3:41 http://www.cardiothoracicsurgery.org/content/3/1/41 LCCA AA LV RA Figure A enhanced (white artery drain coronal (red (LCCA) arrows) 1 CT oblique arrow) coronary and originating into image running the angiogram from from right in the anatrium the ECG-gated, atrio-ventricular depicting left(RA) circumflex a tortuous contrastgroove coronary fistula to A coronal oblique image from an ECG-gated, contrast-enhanced CT coronary angiogram depicting a tortuous fistula (white arrows) originating from the left circumflex coronary artery (LCCA) and running in the atrio-ventricular groove to drain (red arrow) into the right atrium (RA). onary arteries (5%)[2]. CAF can be congenital or acquired. Congenital CAF are thought to arise as a result of incomplete embryonic development; normally the coronary arteries communicate with the great vessels and chambers of the heart via sinusoids and during development these AA PA LA Figure An nary ning ascending the axial left in CTthe atrium 2image angiogram aorta atrio-ventricular (LA) from (AA) depicting anand ECG-gated, communicating groove the fistula contrast-enhanced, posterior (white (redto arrow) the with runcoroAn axial image from an ECG-gated, contrastenhanced, coronary CT angiogram depicting the fistula (white arrow) running in the atrio-ventricular groove posterior to the ascending aorta (AA) and communicating (red arrow) with the left atrium (LA). Pulmonary artery (PA). PA LA Figure An nary strates depicts axial CTthe the 3image angiogram tortuous fistula from draining atan nature a ECG-gated, level into ofjust the thecaudal fistula left contrast-enhanced atrium to (white figure (LA) arrows) 2 demoncoroand An axial image from an ECG-gated, contrastenhanced coronary CT angiogram at a level just caudal to figure 2 demonstrates the tortuous nature of the fistula (white arrows) and depicts the fistula draining into the left atrium (LA). sinusoids transform into a normally calibrated capillary network. It has been postulated that incomplete closure of these sinusoids can result in CAF[3]. Acquired CAF can occur as a result of inflammation, atherosclerosis, and trauma or collagen vascular disease [4]. Previously the diagnosis of CAF has been made using conventional coronary angiography. With the advent of dual tube multidetector CT superior imaging can be now obtained using coronary CTA as described in this case. The patient's angiogram suggested that the fistula was draining into the pulmonary artery. However at the time of surgery the fistula was in fact draining into the right atrium and also communicating with the left atrium, which was clearly demonstrated in a non-invasive manner using coronary CTA. Coronary CTA is a relatively new imaging modality that has been used for non-invasive coronary artery imaging since 2000 [5]. Prior to this earlier systems produced images that were of poor quality due to limitations with spatial and temporal resolution and image noise [6]. With the introduction of multi-detector computed tomography (MDCT) many problems with image quality h (...truncated)