An Unreported Type of Coronary Artery Anomaly in Congenitally Corrected Transposition of Great Arteries 선천성수정대혈관전위환자에서새롭게보고된관상동맥변이

Transcription

1 Case Report pissn / eissn J Korean Soc Radiol 2016;75(1): An Unreported Type of Coronary Artery Anomaly in Congenitally Corrected Transposition of Great Arteries 선천성수정대혈관전위환자에서새롭게보고된관상동맥변이 Min Kyu Kwak, MD 1, Yeon Joo Jeong, MD 1, Geewon Lee, MD 1, Nam Kyung Lee, MD 1, Jung Hyun Choi, MD 2, Ji Won Lee, MD 1 * Departments of 1 Radiology, 2 Internal Medicine, Medical Research Institute, Pusan National University Hospital, Busan, Korea Coronary artery variations are associated anomalies in 45% of congenitally corrected transposition of the great arteries (cctga) cases, and it is important to detect any coronary artery anomalies before cardiac surgery. We report a case of a 51-year-old woman with cctga and an unreported type of coronary artery anomaly. Index terms Congenital Abnormalities Heart Coronary Artery Disease Multidetector Computed Tomography Received December 31, 2015 Revised February 26, 2016 Accepted March 5, 2016 *Corresponding author: Ji Won Lee, MD Department of Radiology, Medical Research Institute, Pusan National University Hospital, Pusan National University School of Medicine, 179 Gudeok-ro, Seo-gu, Busan 49241, Korea. Tel Fax jw@pusan.ac.kr This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. INTRODUCTION CASE REPORT Congenitally corrected transposition of the great artery (cct- GA) is a rare congenital anomaly, accounting for 0.05% of congenital heart malformations (1). Most patients have associated cardiac anomalies, including ventricular septal defects, pulmonary stenosis, and systemic atrioventricular (AV) valve, conduction abnormality, and coronary anomalies (2). The identification of the coronary artery anatomy is essential in the preoperative evaluation for optimal surgical outcome (3) and can be evaluated using cardiac computed tomography (CT). Here, we describe a 51-year-old woman who had cctga with a new type of coronary artery anomaly detected on cardiac CT. This study was approved by the Institutional Review Board of our hospital. The requirement for patient informed consent was waived because of the retrospective nature of the study. A 51-year-old woman presented with nonspecific chest pain. The electrocardiogram (ECG) showed complete AV block with junctional bradycardia. Echocardiography showed that the aorta was located anterior to and left of the pulmonary artery. The left-sided AV valve was closer to the apex than was the rightsided AV valve, and there was a moderator band in the left-sided ventricle. The ejection fraction of the left-sided ventricle was preserved (50%). Moderate left-sided AV valve regurgitation, mild to moderate aortic valve regurgitation, and mild pulmonary regurgitation were also seen. Subsequently, retrospective ECG-gated CT angiography was performed using a 64-slice CT scanner (Somatom Definition, Siemens Healthcare, Forchheim, Germany) and a standard protocol with a collimation of mm, gantry rotation time of 0.33 ms, and pitch of The tube voltage was 120 kvp, with a 62 Copyrights 2016 The Korean Society of Radiology

2 Min Kyu Kwak, et al tube current of 336 ma and ECG-dependent tube current modulation (60 80% RR-interval). Scan delay times between the start of contrast injection and scanning were determined using the test bolus technique. After a 10 ml intravenous injection of iopamidol (Pamiray 370; 370 mg iodine/ml, Dongkook Pharma, Seoul, Korea) followed by 20 min of saline at 5 ml/s, optimal delay times were determined by automatic evaluation of contrast enhancement in the ascending aorta. Contrast-enhanced cardiac CT was performed using the triple phase injection method (60 ml iopamidol followed by 30 ml 30% blended iopamidol with saline and 20 ml saline at 5 ml/s). The dose-length product for the scan was 638 mgy cm, with an estimated effective radiation dose of 8.9 msv. For image analysis, traditional axial images and all the other available techniques (multiplanar reconstructions, curved multiplanar reformation, maximum intensity projection and 3D volume rendering images) were used. Cardiac CT angiography showed similar findings to those of echocardiography (Fig. 1A-C) and revealed an unusual coronary artery pattern (Fig. 1D, E). The aorta was anterior and to the left of the pulmonary artery. The anterior right sinus had two A B C Fig. 1. An unreported type of coronary artery anomaly in congenitally corrected transposition of great arteries. A. Axial CT image shows the aorta anterior to and left of the pulmonary trunk, suggestive of levo-transposition of the great vessels. B. Axial CT image shows that the left-sided AV valve (black arrowhead) lies closer to the apex than does the right-sided AV valve (white arrowhead). A moderator band (arrow) and prominent trabeculation are seen in the left-sided ventricle. C. The three-chamber view of the left-sided ventricle shows a tricuspid-aortic fibrous discontinuity (black arrow) caused by the presence of the right ventricular infundibulum (left). The three-chamber view of the right-sided ventricle shows mitral-pulmonary fibrous continuity (right). Ao = aorta, AV = atrioventricular, CT = computed tomography, LA = left atrium, LV = morphological left ventricle, PA = pulmonary artery, RA = right atrium, RV = morphological right ventricle jksronline.org J Korean Soc Radiol 2016;75(1):

3 An Unreported Type of Coronary Artery Anomaly in Congenitally Corrected Transposition of Great Arteries ostia. The anterior descending and circumflex arteries arose from the first ostium. The circumflex artery coursed in the right AV groove, and the anterior descending artery coursed in the anterior interventricular groove. The right ventricular artery arose from the second ostium in the anterior right sinus. It coursed in the left AV groove around the back of the pulmonary artery and sup- D E Fig. 1. An unreported type of coronary artery anomaly in congenitally corrected transposition of great arteries. D. Oblique axial MIP and 3D VR images show coronary arteries arising from three separate coronary ostia. A stair-step artifact (*) resulting from the irregular heart rhythm in the proximal segment of the circumflex artery arising from the anterior right sinus is also seen. The aortic valve has three cusps, which are located to the left anteriorly, right anteriorly, and posteriorly. The right ventricular branch (white arrowhead), which runs along the wall on the morphological right ventricle, originates from the anterior left sinus. The circumflex and anterior descending arteries arise from one ostium (black arrow) of the anterior right sinus. The right ventricular artery (white arrow) originates from the other ostium of the anterior right sinus. Another right ventricular branch (black arrowhead) originates from the posterior sinus. E. Axial MIP and 3D VR images show the right ventricular artery arising from the anterior right sinus traveling along the left AV groove with a retropulmonary course (white arrow). al = anterior left sinus, ar = anterior right sinus, CT = computed tomography, LA = left atrium, LV = morphological left ventricle, MIP = maximum intensity projection, p = posterior sinus, PA = pulmonary artery, RA = right atrium, RV = morphological right ventricle, 3D VR = 3D dimensional volume-rendered 64 J Korean Soc Radiol 2016;75(1):62-67 jksronline.org

4 Min Kyu Kwak, et al plied the morphological right ventricle. The anterior left sinus had a single ostium giving rise toa right ventricular branch, which ran along the wall of the morphological right ventricle. Finally, the right ventricular artery from the posterior sinus travelled along the left AV groove. These are illustrated in Fig. 2. The patient was diagnosed with cctga with a coronary artery anomaly. She is currently being followed regularly for the development of heart failure. DISCUSSION cctga is an unusual cardiac malformation with AV and ventriculoarterial (VA) discordance. AV discordance means that the morphological left atrium discharges blood into the morphological right ventricle, and the morphological right atrium drains into the morphological left ventricle. VA discordance means that the morphological right ventricle connects to the aorta, and the morphological left ventricle connects to the pulmonary artery. This double discordance results in physiologically corrected circulation, with the morphological left ventricle supplying the pulmonary circulation, and the morphological right ventricle supporting the systemic circulation (1). Most patients have associated cardiac anomalies, including ventricular septal defects in 70% of patients, pulmonary stenosis in approximately 40%, systemic AV valve abnormalities in up to 90%, coronary anomalies in 45%, and complete heart block in 30% (2, 4, 5). The natural history of a patient with cctga is variable, and the prognosis depends on AV conduction, arrhythmias, structural abnormalities, and the degree of hemodynamic disturbance (6). It is important to identify any associated coronary artery anomalies if surgery, particularly a double switch operation, is considered (7). In this report, the left and right ventricular arteries are defined by the ventricle they supply, and the circumflex artery is that which runs in the left AV groove. The anterior descending artery is that which follows the interventricular septum (4). A universal, systemic, descriptive classification for coronary arteries and great vessel anatomy is required to allow accurate description and rapid communication of the pattern of abnormalities between radiologist, cardiologist, and surgeons. Although several classification schemes for coronary artery anomalies have been developed, no uniform classification is widely used because they are based on relatively small sample sizes and cannot be applied to variable congenital heart disease (8). Recently, Sithamparanathan et al. (8) suggested a new classification of great vessel and coronary artery anatomy in transposition and other coronary anomalies using cardiac CT. It includes both descriptive classification for clinical purpose and an alphanumeric classification for taxonomy and research. This simple, universal codex allows delineation of the coronary anatomy, anatomical relationship of the aorta to the pulmonary artery, as well as application to all congenital heart disease patients. It also Our case Typical type Anterior descending artery Right ventricular branch Anterior descending artery Conal branch Circumflex artery Circumflex artery Ventricular branch Anterior Right ventricular branch Right Left Right ventricular artery Right ventricular artery Posterior Fig. 2. Diagrams of the coronary anatomy showing our case and typical cctga. Dashed lines represent variably present branches. cctga = congenitally corrected transposition of the great arteries jksronline.org J Korean Soc Radiol 2016;75(1):

5 An Unreported Type of Coronary Artery Anomaly in Congenitally Corrected Transposition of Great Arteries provides the prognostic information by description about interarterial malignant course and the number of coronary ostia in each aortic sinus. However this new classification needs to be clinically validated in the near future. Therefore, the manner in which we described our CT findings is partially adapted from previous reports (4, 8, 9). Our patient had cctga combined with a coronary artery anomaly detected on cardiac CT. Ismat et al. (4) reported several coronary anomalies in 10 cctga patients and described the typical orientation of the coronary arteries (Fig. 2). Typically, the right ventricular artery arises from the posterior sinus, and the anterior descending and circumflex arteries branch from a common left ventricular coronary artery from the anterior right sinus. Compared with this typical type, our patient had two additional ostia located in the right and anterior left sinuses. The first additional coronary artery was a right ventricular branch from the anterior left sinus, and the second additional coronary artery was a right ventricular artery with a retropulmonary course originating from the anterior right sinus. Chiu et al. (10) classified the coronary artery types in cctga into five patterns according to similarities in the epicardial configuration at the base of the heart. However, our patient did not concord with any of these five patterns. We report an unreported coronary artery anomaly in a cct- GA patient. Knowledge of this coronary artery anomaly is a prerequisite for surgical correction, and cardiac CT is useful for detecting combined coronary artery anomalies. Acknowledgments This work was supported by a 2015 Clinical Research Grant from Pusan National University Hospital. REFERENCES 1. Wallis GA, Debich-Spicer D, Anderson RH. Congenitally corrected transposition. Orphanet J Rare Dis 2011;6:22 2. Warnes CA. Transposition of the great arteries. Circulation 2006;114: Huang SC, Chiu IS, Lee ML, Wu CS, Chiu HH, Chang CI, et al. Coronary artery anatomy in anatomically corrected malposition of the great arteries and their surgical implications. Eur J Cardiothorac Surg 2011;39: Ismat FA, Baldwin HS, Karl TR, Weinberg PM. Coronary anatomy in congenitally corrected transposition of the great arteries. Int J Cardiol 2002;86: Friedberg DZ, Nadas AS. Clinical profile of patients with congenital corrected transposition of the great arteries. A study of 60 cases. N Engl J Med 1970;282: Malhotra S, Patel RN, Mandawat M. A case of congenitally corrected transposition of the great arteries with rare but life-threatening ventricular tachycardia and a coincidental single coronary ostium. J Invasive Cardiol 2007;19:E139- E Karl TR. The role of the fontan operation in the treatment of congenitally corrected transposition of the great arteries. Ann Pediatr Cardiol 2011;4: Sithamparanathan S, Padley SP, Rubens MB, Gatzoulis MA, Ho SY, Nicol ED. Great vessel and coronary artery anatomy in transposition and other coronary anomalies: a universal descriptive and alphanumerical sequential classification. JACC Cardiovasc Imaging 2013;6: Kantarci M, Koplay M, Bayraktutan U, Gundogdu F, Ceviz N. Congenitally corrected transposition of the great arteries: MDCT angiography findings and interpretation of complex coronary anatomy. Int J Cardiovasc Imaging 2007;23: Chiu IS, Wu SJ, Chen SJ, Wang JK, Wu MH, Lue HC. Sequential diagnosis of coronary arterial anatomy in congenitally corrected transposition of the great arteries. Ann Thorac Surg 2003;75: J Korean Soc Radiol 2016;75(1):62-67 jksronline.org

6 Min Kyu Kwak, et al 선천성수정대혈관전위환자에서새롭게보고된관상동맥변이 곽민규 1 정연주 1 이지원 1 이남경 1 최정현 2 이지원 1 * 선천성수정대혈관전위환자의 45% 에서관상동맥변이를동반하고있으며, 심장수술을시행하기전에이러한관상동맥변이를찾는것은중요하다. 우리는선천성수정대혈관전위가있는 51 세여자환자에서발견된관상동맥변이를보고하고자하며, 이는이전문헌에서는보고되지않았던종류의변이이다. 부산대학교병원 1 영상의학과, 2 내과 jksronline.org J Korean Soc Radiol 2016;75(1):