Imaging of coronary artery anomalies
Transkript
Imaging of coronary artery anomalies
Diagnostic methods 203 Imaging of coronary artery anomalies: the role of multidetector computed tomography Fehmi Kacmaza, Nilgun Isiksalan Ozbulbulb, Omer Alyana, Orhan Madena, Ahmet Duran Demira, Yucel Balbaya, Ali Riza Erbaya, Ramazan Ataka, Kubilay Senena, Tulay Olcerb and Erdogan Ilkayc Background Coronary artery anomalies are evaluated by using catheter-based angiography. Multidetector row-computed tomography (MDCT) is a new noninvasive imaging technique that has excellent spatial resolution for detecting the origin and course of a coronary anomalous vessel. Objective To determine the sensitivity of multidetector computed tomography in patients who had coronary artery anomaly demonstrated by conventional coronary angiography. Material and methods A retrospective evaluation to identify 23 patients, who underwent retrospective electrocardiographic (ECG)-gated MDCT, was done and in whom an anomalous coronary vessel was found at a single center. Metoprolol (50–100 mg) was given orally to all patients to reduce heart rate so as to get high-quality MDCT images. After performing MDCT, the CT scans of each patient were analysed and compared with their coronary angiograms by two experienced radiologists and one cardiologist who were unaware about the study, and the sensitivity of MDCT was determined. Results Twenty-three patients (age range 28–73) with seven different coronary arteries of the anomalous type were evaluated. Nineteen patients had an anomalous left coronary artery; three patients had an anomalous single coronary artery; and one patient had an anomalous right coronary artery. The most common anomaly type was the Introduction The origin of the coronary artery anomalous is a rare congenital condition with an incidence ranging from 0.17% in autopsy cases [1] to 1.2% in angiographically evaluated cases [2]. Most of these anomalous conditions are not clinically important. Nonfatal or fatal acute myocardial infarction can, however, occur in such patients, [3,4] most notably among young athletes [5,6]. In some cases the aberrant vessel, which passes between the aorta and the main pulmonary artery, can cause a risk for sudden death, particularly if the vessel supplies the left coronary artery distribution [7]. Coronary artery bypass grafting may be indicated for such patients [8]. c 2008 Wolters Kluwer Health | Lippincott Williams & Wilkins 0954-6928 left circumflex coronary artery (52%). The origin and course of all anomalous vessels were detected by ECG-gated MDCT (Lightspeed 16, GE Medical Systems, Milwaukee, Wisconsin, USA). The sensitivity of 100% of MDCT was detected in patients who had anomalous coronary vessels. Conclusion We suggest that MDCT could be a noninvasive alternative imaging technique to conventional coronary angiography for screening the anomalous vessels of coronary arteries because of its excellent spatial resolution, which is very important for detecting the relationship of anomalous vessels with great arteries and c 2008 cardiac structures. Coron Artery Dis 19:203–209 Wolters Kluwer Health | Lippincott Williams & Wilkins. Coronary Artery Disease 2008, 19:203–209 a Cardiology Clinics, Turkish Society of Cardiology, bDepartment of Radiology, Turkiye Yuksek Ihtisas Hospital, Turkish Society of Radiology and cDepartment of Cardiology, Mesa Hospital, Fellow of European Society of Cardiology, Ankara, Turkey Correspondence to Dr Fehmi Kacmaz, MD, Bingol Devlet Hastanesi, Kardiyoloji klinigi, 12100 Duzagac-Bingol, Turkey Tel: + 90 426 214 14 00; fax: + 90 312 310 03 78; e-mail: kacmazfehmi@superonline.com or drfehmikacmaz@yahoo.com This manuscript has been accepted as a poster presentation at the 7th International Congress on Coronary Artery Disease in Venice, Italy 2007. Received 21 August 2007 Revised 15 November 2007 Accepted 5 December 2007 Coronary artery anomalies are evaluated by using catheter-based angiography, which is known as the gold standard for imaging methods. In addition to coronary angiography, transesophageal echocardiography [9–11] may also clinically detect coronary anomalies, but this method is not totally non-invasive and is too costly for screening large populations. Contrast-enhanced electron beam tomography has also been recommended [12]. It offers excellent spatial resolution and identifies most anomalies of the coronary course. Magnetic resonance imaging (MRI) has often been used to determine the coronary artery anomalous in equivocal cases. MRI can, however, be limited by low spatial resolution and artifacts and can be technically challenging [13]. Multidetector 204 Coronary Artery Disease 2008, Vol 19 No 3 row-computed tomography (MDCT) is a new imaging technique developed recently, and its importance is gradually increased in the area of cardiac imaging. Therefore, we aimed to determine the sensitivity of MDCT in 23 patients who had an coronary artery anomalous detected by coronary angiography initially in a single center. Materials and methods Patients Between June 2005 and February 2007, a total of 9341 consecutive patients underwent coronary angiography, and 23 patients with anomalous coronary arteries were identified. All patients were admitted to the hospital with a complaint of angina and/or dyspnea. Patients who had atrial fibrillation were excluded. Patient preparation included instruction to avoid caffeine on the day of the study. Metoprolol (50–100 mg) was administered orally 3 days before the MDCT scan to decrease the heart rate and to obtain optimal images. We performed MDCT on all patients who had coronary artery anomaly detected initially by coronary angiography. All patients were orally informed about study in clear terms; the study was started after patients gave written informed consent; and the study protocol was approved by the institutional review board. To detect the realistic sensitivity of MDCT, the results of MDCT were evaluated by two experienced radiologists and one cardiologist, all of whom were unaware of the study. Finally, we determined the diagnostic sensitivity of MDCT in patients who had coronary artery anomaly. Multidetector row-computed tomography image and data analysis Patients with angiographically documented coronary artery anomaly underwent 16-slice CT coronary angiography. Medications were not discontinued throughout the angiographic and MDCT studies. MDCT (16-light speed, General Electric, Milwaukee, Wisconsin, USA) was performed 2 to 3 weeks later to prevent contrast agent nephropathy secondary excessive contrast agent. All image acquisitions were obtained in the craniocaudal direction and in the supine position during inspiratory breath hold preceded by mild hyperventilation and inhalation of oxygen (2–3 lt/min) for 5 min. First, noncontrast localization scan was performed that yielded an anteroposterior view of the chest; it was used to position the imaging volume for coronary artery imaging, which extended from the carina to 10 mm below the diaphragmal face of the heart. In a second step, a bolus of 30 ml of contrast agent (Iohexol, Ultravist 350, Schering AG, Berlin, Germany) was injected intravenously at 4 ml/s via an 18-gauge catheter placed in the antecubital vein. After a delay of 10 s, a sequence of 10 axial images at the level of the carina was acquired with an interval of 2 s between subsequent images. From the time interval between contrast agent injection and acquisition of the images with peak attenuation in the aortic root, the contrast agent transit time was determined. In a third step, contrast agent (130 ml) was injected into antecubital vein at 4 ml/s, and the CT scan was initiated after a delay according to the previously determined contrast agent transit time. The volume data set for coronary artery visualization was acquired (16 0.625 mm detector configuration, table feed 3 mm/rotation, pitch 0.3, rotation time 0.5 s, tube voltage of 120 kV). After the acquisition of the raw spiral data, retrospective ECG synchronized slices were reconstructed at 75% of the R–R interval. These images were transferred to a workstation for processing AW4.2 (Advantage Windows 4.2, GE, Medical Systems, Wisconsin, USA). Axial, sagittal, coronary multiplanar reformations, and three-dimensional images were created using standard software. MDCT images were analyzed by two experienced radiologists and one cardiologist, all of whom were unaware of study. Results Patient characteristics and scan parameters are shown in Table 1. Twenty-three patients (15 males, 8 females; age range 28–73 years), who had coronary artery anomaly detected by coronary angiography, were evaluated. All patients had sinus rhythm. The heart rates of the patients were ranged between 48 and 66 bpm. Coronary artery anomaly type and course of anomalous coronary vessels In this study, we detected seven different types of coronary artery anomalous when we analyzed all coronary Table 1 Patients’ characteristics and scan parameters of each patient Patient no. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Age/sex Heart rate during scan (bpm) Contrast transit time (s) Z-axis coverage 44/M 59/M 28/F 67/M 64/M 57/M 61/M 61/F 73/M 56/F 48/M 52/F 65/M 42/M 59/M 54/F 67/F 54/F 57/M 61/M 71/M 60/M 56/F 48/56 64/66 60/65 54/58 62/68 56/62 60/62 58/61 64/68 60/61 63/68 60/66 65/66 48/56 64/66 62/65 53/58 62/65 54/62 60/62 58/61 60/66 60/60 24 20 19 22 19 21 20 22 18 20 19 19 19 24 20 19 23 19 21 20 22 18 20 90 120 90 90 120 120 90 120 90 90 120 90 120 90 120 90 90 120 120 90 120 90 120 bpm, beat per minute; F, female; M, male; s, second. Imaging of coronary artery anomalies Kacmaz et al. 205 angiography and MDCT images. Nineteen (82%) patients had anomalous left coronary artery; three (13%) patients had single coronary artery and one (5%) patient had anomalous origin of right coronary artery (RCA). Origin and course of all anomalous coronary arteries were shown by multidetector computed tomography and diagnostic sensitivity equal to 100% for MDCT was identified. Left coronary artery anomalies were also separated as being of anomalous origin in the left main coronary artery, the left anterior descending coronary artery (LAD), and left circumflex coronary artery (LCX). The anomalous origin of LCX [12 of 23 (52%) patients] was the most anomalous type in this study. The origin of 11 of 12 anomalous vessels of LCX began in the right sinus of Valsalva and has passed retroaortic vessels and coursed through sulcus atrioventricularis (Fig. 1); one anomalous vessel originated from the distal portion of RCA. The remaining three of 19 (13%) patients with an anomalous origin of the left coronary artery had an anomalous origin in the left main coronary artery (all arose from the right sinus of Valsalva). Three (13%) patients had anomalous origin of the left anterior descending coronary artery (which arose from the right sinus of Valsalva). One patient had an anomaly of the double left anterior descending coronary artery and that anomalous vessel originated from the right sinus of Valsalva and had coursed anteriorly to the main pulmonary artery (Fig. 2a–d). Origin and courses of all anomalous vessels have been determined in Table 2. Fig. 1 Single coronary arteries have arisen from the right sinus of Valsalva in two patients and the left sinus of Valsalva in one patient. The single coronary arteries originating from the right sinus of Valsalva have coursed anteriorly to the main pulmonary artery (Figs 3a–c and 4). In this study, one patient had an anomalous origin of the right coronary artery arising from the left sinus of Valsalva. In this the patient anomalous vessel has coursed between the main pulmonary artery and the aorta (Fig. 5). Ten of 23 (43%) patients also had atherosclerotic coronary artery disease (in four patients with single vessel disease, in five patients with two-vessel disease, and in one patient with three-vessel disease). One patient had a muscular bridge at the distal portion of the left anterior descending coronary artery. Coronary bypass grafting operation was recommended for patients who had three-vessel disease. In the remaining patients, percutaneous coronary intervention was performed. Discussion Here we demonstrated a diagnostic sensitivity of 100% of MDCT for the detection of the origin and course of the anomalous vessel in patients who had coronary artery anomaly. Coronary artery anomalies are found in about 1% of patients undergoing cardiac catheterization [8]. Three types of ectopic anomalies have been described in the current literature: (i) ectopic origin from coronary sinus, (ii) absent coronary artery, (iii) ectopic origin from a main pulmonary artery. The first two types of anomaly are most common in adults. Another type of anomaly is a coronary arterivenous fistula, which accounts for approximately 13% of coronary anomalies [8,14]. Approximately 20% of coronary anomalies have been implicated in chest pain, sudden death, cardiomyopathy, syncope, dsypnea, ventricular fibrillation, and myocardial infarction [15]. Coronary artery anomalies are the second most common cause of death because of structural heart disease in young athletes [16]. The left main coronary artery arising from the right sinus of Valsalva can cause exercise angina, myocardial infarction, syncope, and sudden death. In particular, an anomalous vessel that crosses between the aorta and the main pulmonary artery, either a left coronary artery originating from the right sinus or a right coronary artery arising from the left sinus, may be associated with a poor prognosis [17,18]. Available imaging methods for coronary anomalies A 44-year-old patient had exercise angina: three-dimensional volume rendering (VR) view of an anomalous left circumflex artery (LCX) originating from the right sinus of Valsalva. Transthoracic echocardiography (TTE) is a practical diagnostic test for the detection of the origin of coronary artery abnormalities if specific attention is paid to the coronary arteries. This may provide a diagnosis by identifying anomalous arterial origins, delineate whole fistulous courses, and characterize their hemodynamic status, size and function of the receiving chambers, which may reflect potentially adverse effects of a coronary steal. 206 Coronary Artery Disease 2008, Vol 19 No 3 Fig. 2 A 64-year-old man had exercise stable angina: (a) Three-dimensional volume rendering (VR) image and (b) axial thick slab maximum intensity projection (MIP) show double left anterior descending coronary artery (LAD). Short arrow shows anomalous left anterior descending artery arising from right sinus of Valsalva. Long arrow shows normal anatomic coursing of left anterior descending artery arising from left sinus of Valsalva. (c) Right oblique cranial coronary angiography image shows left anterior descending coronary artery arising from right sinus of Valsalva. (d) Right oblique caudal angiographic image shows normal coursing LAD originated from left sinus of Valsalva. Table 2 Origin and course of anomalous vessels of each patient detected by multidetector computed tomography Patient no. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Anomalous vessel Origin of anomalous vessel LCX LCX LMCA LCX LCX LCX LCX LAD LAD LCX RCA LCX LCX LCX LCX LMCA Single LAD LCX LMCA Single Single Double LAD RSV RSV RSV RSV RSV RSV RSV RSV RSV RSV LSV RSV RSV RSV RCA RSV LSV RSV RSV RSV RSV RSV Anomalous vessel from RSV Course of anomalous vessel Retroaortic Retroaortic Anterior to pulmonary artery Retroaortic Retroaortic Retroaortic Retroaortic Antrior to right ventricle Retroaortic Retroaortic Between aort and pulmonary artery Retroaortic Retroaortic Retroaortic Sulcus atrioventricularis Retroaortic RCA: retroaortic, LMCA: anterior to pulmonary artery Anterior of right ventricle Retroaortic Retroaortic LCX: Retroaortic, LAD: Anterior to pulmonary artery LCX: Retroaortic, LAD: Anterior to pulmonary artery Anomalous AD vessel: anterior to pulmonary artery AD, anterior descending coronary artery; LAD, left anterior descending coronary artery; LCX, left circumflex coronary artery; LMCA, left main coronary artery; RCA, right coronary artery; RSV, right sinus of Valsalva. Imaging of coronary artery anomalies Kacmaz et al. 207 Fig. 3 A 67-year-old female patient had complaint of stable exercise angina: (a) Three-dimensional volume rendering (VR) view of an anomalous left circumflex artery (LCX) originating from the right sinus of Valsalva and single coronary artery [arrow shows left anterior descending coronary artery (LAD)]. (b) Multiplanar reformation image shows single coronary artery arising from the right coronary sinus and coursing anterior to the pulmonary artery (arrow). (c) Axial thick slab maximum intensity projection (MIP) shows an anomalous left circumflex artery (LCX) originating from the right sinus of Valsalva and coursing between the left atrium (LA) and aorta (arrow). RCA is also shown (arrowhead). Fig. 4 Fig. 5 A 67-year-old male patient had exercise dyspnea and angina: axial thick slab maximum intensity projection (MIP) shows single coronary artery arising from right sinus of Valsalva (arrow) and coursing anteriorly to the pulmonary artery. A 61-year-old female patient had atypical chest pain: three-dimensional volume rendering (VR) image shows an anomalous RCA originating from the left coronary sinus and coursing between the aorta and pulmonary artery (PA). Moreover, the exact course of the anomalous vessel or coronary artery fistula may not be detected by TTE. Transoesophageal echocardiography also may fail to delineate completely coronary anomalies, and it is not totally noninvasive. Other noninvasive techniques such as nuclear and cineMR cardiac imaging have gained increasing importance in current literature. MR imaging has been the noninvasive imaging method for the identification of congenital coronary artery anomalies and their courses [3,19]. New 208 Coronary Artery Disease 2008, Vol 19 No 3 MR imaging sequences have improved image quality with better anatomical definition and have become an alternative choice to evaluate flow and function [20]. The accuracy rate of magnetic resonance angiography in patients with coronary artery anomalies was differentiated from 93 to 100% in the current literature [6,17,21]. The rate specificity and sensitivity of MR angiography in patients that had coronary anomaly have been shown to be higher than conventional coronary angiography in studies where both imaging techniques are compared. MR coronary angiography is recommended as a new gold standard for diagnostic imaging methods in coronary artery anomalies [17]. The spatial resolution of MR imaging is marginal for coronary artery imaging. Its greatest limitation is in determining the distal arterial course [22]. Furthermore, MRI is limited by low spatial resolution and artifacts; it can be technically challenging [13]. In comparison, MDCT cardiac imaging provides excellent distal coronary artery and side branch visualization. Furthermore, if required, an entire three-dimensional volume of the heart and great vessels may be acquired within 20 s. As opposed to magnetic resonance imaging, which also permits the analysis of coronary anomalies in tomographic images, MDCT requires a radiation and a contrast agent. The high resolution of the data sets (permitting analysis even of small details) and the speed of image acquisition make MDCT reasonable to use as one of the first-choice imaging modalities in the workup of known and suspected coronary anomalies. ECG-controlled dose modulation is now available on most scanners. This method reduces the tube current during systole, resulting in a 30–50% reduction in effective radiation exposure [23]. Dose modulation should be used in all patients with a regular low heart rate (sinus rhythm, < 65 beats per min, low heart rate variability, and absence of arrhythmia). The presence of anomalous coronary arteries can be a differential diagnosis in patients with suspected coronary disease, chest pain, or syncope. Cardiac catheterization has been indicated in detail in the entire coronary vasculature before intervention and has remained the gold standard for imaging modality to visualize coronary anatomy. Accurate diagnosis of anomalous coronary arteries by invasive coronary angiography, however, is limited by the inability to define the anatomic course in relation to surrounding structures. Owing to the potentially complex three-dimensional nature of these anomalies, conventional coronary angiography, infrequently, incompletely delineates the anatomical course of the coronary artery. Therefore, detailed assessment of anomalous coronary arteries, including their origin and course, is difficult with invasive coronary angiography. The threedimensional nature of MDCT coronary angiography data sets allows exact analysis of anomalous coronary arteries. Early reports of using computed tomography (CT) to evaluate coronary artery have emphasized electron beam technology. Ropers et al. [12] used ECG-gated electron beam CT with 3-mm collimation and three-dimensional reconstructions to assess 60 patients, 30 of whom had coronary artery anomalies. Two observers successfully categorized each patient according to the presence or absence of coronary anomalies. Twenty-nine of the 30 anomalies were characterized accurately. Although this study demonstrated the feasibility of CT, electron beam CT is not widely available and is limited by relatively poor z-axis resolution. MDCT angiography is a new imaging method to delineate clearly the origin and course of the coronary artery anomalous. In general, MDCT is substantially faster than MR imaging. The small-section thickness permitted it to obtain volumetric reconstructions of high quality. Although these images were not crucial in the diagnosis of the anomaly, they were valuable for depicting the relationships among the coronary vessel, great vessels, and cardiac chambers. Such images give the surgeons a better understanding of the complex anatomy before repair. As demonstrated in this study, MDCT can differentiate between the precise origin and course with excellent spatial resolution. Some reports had supported our findings in current literature. Schmitt et al. [24] have reported that 28 patients showed an anomalous origin and course of coronary arteries detected by ECG-gated 4-row and 16-row MDCT including thin maximum intensity projection (MIP), multiplanar reformation (MPR), and volume rendering technique (VRT) post-processing compared with coronary angiography. Shi et al. [25] reported a study in which 242 consecutive patients referred for noninvasive coronary CT imaging were reviewed for the study, and 16 patients (6.6%) with anomalous coronary arteries were detected. MDCT and coronary angiography images were analyzed in a blinded fashion for the accuracy of anomalous artery origin and path detection. Results were compared in a secondary consensus evaluation. Coronary anomalies for all 16 patients were correctly displayed on MDCT. Coronary angiography alone achieved correct identification of the abnormality in only 53% (P = 0.016). In another study, Berbarie et al. [26] reported a series of cases of coronary artery anomalies detected by MDCT with up to 64 detector arrays, and in that series of cases, the investigators describe their institution’s experience with CT coronary angiography as a complement to invasive coronary angiography in determining the origin and course of different anomalous coronary arteries in 16 patients. Anomalous coronary arteries were all clearly defined with regard to their origin and course. Deibler et al. [27] described a single-center experience of using retrospectively gated MDCT coronary angiography for the imaging of nine patients diagnosed as having congenital Imaging of coronary artery anomalies Kacmaz et al. 209 coronary anomalies on invasive, selective coronary angiography. In one patient, MDCT showed a normal but extremely anterior origin of the right coronary artery from the right aortic sinus of Valsalva. In the other eight patients, the origin and course of coronary arteries were recognized easily on MDCT. The sensitivity of 16-MDCT in coronary artery anomalies has been showed as 100% in recent studies. Similarly, in our study the origin of all anomalous vessels was shown by conventional coronary angiography and 16-gated MDCT. The course of all anomalous vessels was also shown by MDCT. One hundred percent sensitivity of the 16-row MDCT was detected in this study, as in other recently published studies. In this series, multidetector row-CT angiography provided an accurate depiction of vessel origin and course in this review of 23 anomalous coronary arteries. All patients were referred after coronary angiogram. The results of this study suggest that MDCT is a viable noninvasive modality in the delineation of coronary arterial anomalies, particularly if the results of coronary angiography are equivocal and the course of anomalous vessel is unknown. 4 5 6 7 8 9 10 11 12 13 Conclusion ECG-gated 16-row MDCT is an accurate diagnostic tool to define the origin and course of anomalous coronary vessels. MDCT should be performed for patients that have a coronary artery anomaly, especially when they have symptoms relating to anomalous vessels, because it is able to determine how the anomalous vessel relates with arteries and other cardiac structures. It should therefore be considered as a prime noninvasive imaging tool for suspected coronary artery anomalies. Noninvasiveness and precise visualization characteristics of MDCT make it a standard reference for evaluating anomalous coronary arteries. 14 15 16 17 18 19 Study limitations Having evaluated 23 patients with coronary artery anomalies, the current numbers are low enough to determine exact sensitivity of MDCT compared with coronary angiography. Therefore, we need a large series of tests to obtain a realistic sensitivity of MDCT. One of the other study limitations is that MDCT was performed on all patients after coronary angiography. Therefore, all MDCT images were evaluated by two radiologists and one cardiologist, who were unaware of the coronary angiography results. References 1 2 3 Alexander RW, Griffith GC. Anomalies of the coronary arteries and their clinical significance. Circulation 1956; 14:800–805. Engel HJ, Torres C, Page HL. Major variations in anatomical origin of the coronary arteries: angiographic observations in 4250 patients without congenital heart disease. Cathet Cardiovasc Diagn 1975; 1:157–169. Kaku B, Kanaya H, Ikeda M, Uno Y, Fujita S, Kato F, et al. Acute inferior myocardial infarction and coronary artery spasm in a patient with an 20 21 22 23 24 25 26 27 anomalous origin of the right coronary arteryfrom the left sinus of Valsalva. Jpn Circ J 2000; 64:641–643. Benge W, Martins JB, Funk DC. Morbidity associated with anomalous origin of the right coronary artery from the left sinus of Valsalva. Am Heart J 1980; 99:96–100. Maron BJ, Epstein SE, Roberts WC. Sudden death in young competitive athletes. J Am Coll Cardiol 1986; 7:204–214. Basso C, Maron BJ, Corrado D, Thiene G. Clinical profile of congenital coronary artery anomalies with origin from the wrong aortic sinus leading to sudden in young competitive athletes. J Am Coll Cardiol 2000; 35: 1493–1501. Benson PA. Anomalous aortic origin of coronary artery with sudden death: case report and review. Am Heart J 1970; 79:254–257. Yamanaka O, Hobbs RE. Coronary artery anomalies in 126 595 patients undergoing coronary angiography. Cathet Cardiovasc Diagn 1990; 21:28–40. Gaither NS, Rogan KM, Stajduhar K, Banks AK, Hull RW, Whitsitt T, Vernalis MN. Anomalous origin and course of coronary arteries in adults: identification and improved imaging utilizing transesophageal echocardiography. Am Heart J 1991; 122 (1 Pt 1):69–75. Fernandes F, Alam M, Smith S, Khaja F. The role of transesophageal echocardiography in identifying anomalous coronary arteries. Circulation 1993; 88:2532–2540. Giannoccaro PJ, Sochowski RA, Morton BC, Chan KL. Complementary role of transoesophageal echocardiography to coronary angiography in the assessment of coronary artery anomalies. Br Heart J 1993; 70:70–74. Ropers D, Moshage W, Daniel WG, Jessl J, Gottwik M, Achenbach S. Visualization of coronary artery anomalies and their anatomic course by contrast-enhanced electron beam tomography and three-dimensional reconstruction. Am J Cardiol 2001; 87:193–197. McConnell MV, Ganz P, Selwyn AP, Li W, Edelman RR, Manning WJ. Identification of anomalous coronary arteries and their anatomic course by magnetic resonance coronary angiography. Circulation 1995; 92: 3158–3162. Said SA, el Gamal MI, van der Werf T. Coronary arteriovenous fistulas: collective review and management of six new cases–changing etiology, presentation, and treatment strategy. Clin Cardiol 1997; 20:748–752. Angelini P, Villason S, Chan AV, Diez JG. Normal and anomalous coronary arteries in humans. In: Angelini P, editor. Coronary artery anomalies: a comprehensive approach. Philadelphia: Lippincott Williams & Wilkins; 1999. pp. 27–150. Maron BJ. Sudden death in young athletes. N Eng J Med 2003; 349: 1064–1075. Chetlien MD, De Castro CM, McAllister HA. Sudden death as a complication of anomalous coronary origin from the anterior sinus of Valsalva: a not-so-minor congenital anomaly. Circulation 1974; 50:780–787. Frescura C, Basso C, Thiene G, Corrado D, Pennelli T, Angelini A, Daliento L. Anomalous origin of coronary arteries and risk of sudden death: a study based on an autopsy population of congenital heart disease. Hum Pathol 1998; 29:689–695. Parga JR, Ikari NM, Bustamante LN, Rochitte CE, de Avila LF, Oliveira SA. MRI evaluation of congenital coronary artery fistulae. Br J Radiol 2004; 77:508–511. Duerinckx AJ, Shaaban A, Lewis A, Perloff J, Laks H. 3D MR imaging of coronary arteriovenous fistulas. Eur Radiol 2000; 10:1459–1463. Taylor AM, Thorne SA, Rubens MB, Jhooti P, Keegan J, Gatehouse PD. Coronary artery imaging in grown up congenital heart disease: complementary role of magnetic resonance and X-ray coronary angiography. Circulation 2000; 101:1670–1678. Wielopolski PA, van Geuns RJ, de Feyter PJ, Oudkerk M. Coronary arteries. Eur Radiol 1998; 8:873–885. Hoffmann U, Ferencik M, Cury RC, Pena AJ. Coronary CT Angiography. J Nucl Med 2006; 47:797–806. Schmitt R, Froehner S, Brunn J, Wagner M, Brunner H, Cherevatyy O, et al. Congenital anomalies of the coronary arteries: imaging with contrastenhanced, multidetector computed tomography. Eur Radiol 2005; 15:1110–1121. Shi H, Aschoff AJ, Brambs HJ, Hoffmann MH. Multislice CT imaging of anomalous coronary arteries. Eur Radiol 2004; 14:2172–2181. Berbarie RF, Dockery WD, Johnson KB, Rosenthal RL, Stoler RC, Schussler JM. Use of multislice computed tomographic coronary angiography for the diagnosis of anomalous coronary arteries. Am J Cardiol 2006; 98:402–406. Deibler AR, Kuzo RS, Vohringer M, Page EE, Safford RE, Patron JN, et al. Imaging of congenital coronary anomalies with multislice computed tomography. Mayo Clin Proc 2004; 79:1017–1023.