Coronary artery to pulmonary artery fistulae with multiple aneurysms: radiological features on dual-source 64-slice CT angiography

Coronary artery fistula is a rare vascular anomaly in which there is abnormal communication between the coronary artery and the great vessels or cardiac chambers. We report the case of a 66-year-old man with two separate coronary artery to pulmonary artery fistulas (one of which demonstrated multiple aneurysms), which were diagnosed on dual-source 64-slice coronary CT and reconfirmed by coronary catheter angiography.     

Magnetic resonance imaging demonstration of anomalous origin of the right coronary artery from the left coronary sinus associated with acute myocardial infarction

Coronary MR angiography can be useful for noninvasive diagnosis of potentially life-threatening coronary artery anomalies. However, there has been no report to date on MR demonstration of acute myocardial infarction associated with right coronary artery anomaly. A 55-year-old man was admitted with chest pain. Catheter coronary angiography revealed an anomalous origin with compression in the proximal segment of right coronary artery. Breath-hold MR angiography using spiral acquisition technique showed that the right coronary artery originated from the left coronary sinus with a separate os. The proximal segment of the artery was compressed by right ventricle outflow tract during the diastolic phase of cine MR imaging. Contrast-enhanced MR imaging 5 minutes after Gd-DTPA injection showed hyperenhancement suggestive of acute myocardial infarction in the posteroinferior wall of the left ventricle.     

Assessment of coronary artery patency after stent placement using magnetic resonance angiography

The ability to noninvasively assess the patency of coronary stents would represent a significant advance. We evaluated the safety and ability of two-dimensional coronary MR angiography In imaging stents and suggesting patency. Coronary MR angiography of 26 coronary stents (Palmaz-Schatz) was performed in 16 patients 39 to 73 years of age. Studies were performed between 2 and 4 months after stent placement. All patients were symptom free at the time of imaging. Coronary MR angiography was performed with a commercial 1.5-T MR imager using an electrocardio-graphically gated pulse sequence with breath-holding. Images were obtained in mid-diastole with and without fat suppression. Image artifacts caused by the metal in the stents were clearly visualized in all 26 stents (100% sensitivity for stent detection). Arterial flow signal was seen in the coronary artery or graft distal to the stent in 25 of 26 cases (96%). All patients, except for the one in which distal flow could not be seen, remained symptom free for >2 years. The distribution of stent locations was as follows: 10 in the right coronary artery (RCA), 10 in the left anterior descending coronary artery (LAD), 2 in the left circumflex coronary artery, and 4 in saphenous vein grafts (SVGs) to RCA. One patient had 2 RCA and 2 LAD stents, one had 3 RCA and 1 LAD stents, one had 3 SVG stents, and two had double RCA stents. Coronary MR angiography is safe for noninvasive imaging of coronary stents, and in the proper clinical setting, it can be used to help suggest patency.     

Coronary artery anomalies and variants: technical feasibility of assessment with coronary MR angiography at 3 T

The purpose of this study was to prospectively use a whole-heart three-dimensional (3D) coronary magnetic resonance (MR) angiography technique specifically adapted for use at 3 T and a parallel imaging technique (sensitivity encoding) to evaluate coronary arterial anomalies and variants (CAAV). This HIPAA-compliant study was approved by the local institutional review board, and informed consent was obtained from all participants. Twenty-two participants (11 men, 11 women; age range, 18-62 years) were included. Ten participants were healthy volunteers, whereas 12 participants were patients suspected of having CAAV. Coronary MR angiography was performed with a 3-T MR imager. A 3D free-breathing navigator-gated and vector electrocardiographically-gated segmented k-space gradient-echo sequence with adiabatic T2 preparation pulse and parallel imaging (sensitivity encoding) was used. Whole-heart acquisitions (repetition time msec/echo time msec, 4/1.35; 20 degrees flip angle; 1 x 1 x 2-mm acquired voxel size) lasted 10-12 minutes. Mean examination time was 41 minutes +/- 14 (standard deviation). Findings included aneurysms, ectasia, arteriovenous fistulas, and anomalous origins. The 3D whole-heart acquisitions developed for use with 3 T are feasible for use in the assessment of CAAV.     

MR多技术扫描检测活性心肌及其和心肌声学造影对比的临床研究

目的 评价MR多技术扫描和心肌声学造影（MCE）在检测心肌灌注、判断心肌存活中的作用。资料与方法 应用MR多技术扫描对36例冠心病患者进行检查,并将结果与冠状动脉造影、MCE结果对照。结果 共有81支冠状动脉狭窄≥70％,狭窄的冠状动脉供血区域为334个（57．99％）节段。MR心肌灌注扫描见268个（46．53％）节段呈缺血改变,MR心肌活性扫描见83个（14．4l％）节段心肌梗死。以冠状动脉造影结果为标准,MR心肌灌注扫描的敏感性为80．2％,特异性为100％,总符合率为88．5％,Kappa值为0．773。定性MCE检查共有202个（35．07％）节段呈缺血改变。以冠状动脉造影结果为标准,定性MCE的敏感性为60．5％,特异性为100％,总符合率为77．1％,Kappa值为0．563。MR心肌灌注扫描所发现的缺血节段比狭窄冠状动脉的供血节段少但无统计学意义（P=0．468）,MCE所发现的缺血节段比狭窄冠状动脉的供血节段少（P=0．000）;MR心肌灌注扫描检出缺血节段比MCE检出的多（P=0．000）。结论 MR多技术扫描可清晰显示心肌缺血或梗死的位置、程度,可重复性好,与冠状动脉造影结果的一致性较高。MCE为临床提供了元创、可重复地准确测定心肌缺血的新方法,但其评价方法具有一定主观性且低估心肌缺血的范围,检查者的经验和检查方法在一定程度上影响其准确性。     

二维屏气结合三维导航技术对冠状动脉磁共振血管造影的研究

目的：研究二维屏气结合三维导航技术对冠状动脉磁共振血管造影的成像,以评价此技术在缺血性心脏病方面的诊断价值,方法：运用１．５Ｔ超导型ＭＲ扫描仪和体部相控制线圈,采用二维屏气下,脂肪抑制,心电门控,Ｋ空间分段采集快速自旋回波（２Ｄ－ｂｒｅａｔｈ－ｈｏｌｄｆａｔ－ｓｕｐｐｒｅｓｓｅｄＥＣＧ－ｇａｔｅｄＦＬＡＳＨｗｉｔｈＫ－ｓｐａｃｅｓｅｇｍｅｎｔａｔｉｏｎ）,多角度双倾斜层面扫描,结合三维导航技术（３     

Coronary artery anomalies: incidence, pathophysiology, clinical relevance and role of diagnostic imaging

Conventional coronary angiography is the gold standard for the diagnosis of coronary artery anomalies. Coronary anomalies are relatively rare findings in patients undergoing conventional coronary angiography for suspected obstructive coronary artery disease. Recently, the increasing performance of diagnostic techniques, such as electron beam tomography (EBT), magnetic resonance (MR) and, more recently, multislice computed tomography (MSCT), has enabled their application to cardiac imaging. MSCT, in particular, has a prominent role in coronary imaging due to its spatial and temporal resolution and three-dimensional capabilities. We report the incidence and pathophysiology of coronary artery anomalies based on the capabilities of recent diagnostic tools with the aim of improving an accurate and noninvasive diagnostic approach.     

Detection of malignant right coronary artery anomaly by multi-slice CT coronary angiography

Coronary artery anomalies occur in 0.3-0.8% of the population and infer a high risk for sudden cardiac death in young adults. Diagnosis is usually established during coronary angiography, which is hampered by poor spatial visualization. Magnetic resonance imaging is an alternative, but it is not feasible in the presence of metal objects or claustrophobia. In this report, a 15-year-old boy experienced ventricular fibrillation and was successfully resuscitated. Cardiac catheterization was inconclusive, and pacemaker implantation prohibited the use of MR imaging. Multi-slice CT coronary angiography revealed a malignant anomalous right coronary artery.     

3D MR imaging of coronary arteriovenous fistulas

Coronary arteriovenous fistula are uncommon if not rare, but represent the most prevalent hemodynamically significant congenital malformations of the coronary arterial circulation. The goal of this report is to evaluate the use of 3D volume rendering from transaxial breathhold coronary MR angiograms to visualize coronary arteriovenous fistulas. Coronary MR angiography offers a new non-invasive technique that accurately defines the anatomy of these malformations, setting the stage for surgical intervention. Received: 15 July 1999; Revised: 13 October 1999; Accepted: 15 October 1999     

Evaluation of Kawasaki’s disease-associated coronary artery aneurysms with 3D CT cinematic rendering

Kawasaki’s disease (KD) is a vasculitis that predominantly affects children and can lead to the development of coronary artery aneurysms. These aneurysms can subsequently thrombose and occlude, which may lead to chest pain and other signs and symptoms of acute coronary syndrome in young patients. Coronary CT angiography, including 3D visualization techniques, is a common modality used in the follow-up of KD patients. In this series of three patients, we present the typical coronary artery imaging findings that can appear in these patients, with an emphasis on the use of the novel 3D technique of cinematic rendering (CR). CR utilizes a different lighting model than other 3D methods and is able to produce highly-detailed, photorealistic images. The potential advantages of CR images in understanding the complex mediastinal vascular anatomy and the relationships of coronary artery aneurysms to other anatomic structures are emphasized.     

MR imaging of coronary artery flow in isolated and in vivo hearts.

Methods for imaging flow in coronary arteries with magnetic resonance (MR) imaging techniques are demonstrated in isolated heart preparations and live animal models. Coronary artery flow was first imaged with a flow-compensated gradient-echo pulse sequence in isovolumic and working perfused rat hearts and then in vivo. A bolus tracking technique was used to measure flow velocity in the coronary arteries. Ultrafast gradient-echo imaging techniques were then applied, with high resolution obtained by combining the information from several cardiac cycles. A stimulated-echo pulse sequence was demonstrated as a method for performing coronary angiography by flow tagging in isovolumic perfused hearts. This report describes the results of coronary flow MR imaging in isolated rat hearts and live mice and rats. The general approach has proved useful in evaluating new methods for coronary MR angiography and should permit well-controlled studies of pathologic conditions. This ability to image coronary flow in isolated hearts and in small animals should permit integrated MR studies of coronary flow, myocardial perfusion, myocardial metabolism, and cellular ionic status.     

Diagnostic performance of stress perfusion and delayed-enhancement MR imaging in patients with coronary artery disease

PURPOSE: To prospectively determine the accuracy of a combined magnetic resonance (MR) imaging approach (stress first-pass perfusion imaging followed by delayed-enhancement imaging) for depicting clinically significant coronary artery stenosis (> or = 70% stenosis) in patients suspected of having or known to have coronary artery disease (CAD), with coronary angiography serving as the reference standard. MATERIALS AND METHODS: The committee on human research approved the study protocol, and all participants gave written informed consent. This study was HIPAA compliant. Forty-seven patients (38 men and nine women; mean age, 63 years +/- 5.3 [standard deviation]) scheduled for coronary angiography were prospectively enrolled: 33 were suspected of having CAD (group A) and 14 had experienced a previous myocardial infarction and were suspected of having new lesions (group B). The MR imaging protocol included cine function, gadolinium-enhanced stress and rest first-pass perfusion MR imaging, and delayed-enhancement MR imaging. Myocardial ischemia was defined as a segment with perfusion deficit at stress first-pass perfusion MR imaging and no hyperenhancement at delayed-enhancement imaging. Myocardial infarction was defined as an area with hyperenhancement at delayed-enhancement imaging. RESULTS: One patient was excluded from analysis because of poor-quality MR images. Coronary angiography depicted significant stenosis in 30 of 46 patients (65%). In a per-vessel analysis (n = 138), stress first-pass perfusion MR imaging and delayed-enhancement imaging yielded sensitivity of 0.87, specificity of 0.89, and accuracy of 0.88, when compared with coronary angiography. The diagnostic accuracy of stress first-pass perfusion MR imaging and delayed-enhancement imaging was slightly better than that of stress and rest first-pass perfusion MR imaging in the entire population (0.88 vs 0.85), in group A (0.86 vs 0.82), and in group B (0.93 vs 0.90). CONCLUSION: Stress first-pass perfusion MR imaging followed by delayed-enhancement imaging is an accurate method to depict significant coronary stenosis in patients suspected of having or known to have CAD.     

Noninfarcted myocardium: correlation between dynamic first-pass contrast-enhanced myocardial MR imaging and quantitative coronary angiography

PURPOSE: To determine the accuracy of first-pass contrast material-enhanced stress myocardial magnetic resonance (MR) imaging for depiction of myocardial ischemia in patients without myocardial infarction. MATERIALS AND METHODS: First-pass contrast-enhanced MR images of the entire left ventricle were acquired in 104 patients at rest and during dipyridamole-induced stress by using an interleaved notched saturation technique. Coronary angiography was performed in all patients, and stress perfusion single photon emission computed tomography (SPECT) was performed in 69 patients. Receiver operating characteristic curve analysis was performed to compare the diagnostic accuracies of first-pass contrast-enhanced stress MR imaging and stress SPECT, with coronary angiography as the reference standard. RESULTS: The overall sensitivity of MR imaging for depicting at least one coronary artery with significant stenosis was 90% (69 of 77 patients). The sensitivities of MR imaging for depiction of single-, double-, and triple-vessel stenoses were 85% (33 of 39 patients), 96% (22 of 23 patients), and 100% (15 of 15 patients), respectively. The specificity of MR imaging for identification of patients with significant coronary artery stenoses was 85% (23 of 27 patients). The areas under the receiver operating characteristic curve for detection of significant stenosis in individual coronary arteries were 0.888 (observer 1) and 0.911 (observer 2) for MR imaging and 0.707 (observer 1, P <.001) and 0.750 (observer 2, P <.001) for SPECT. CONCLUSION: In patients without myocardial infarction, stress enhancement at dynamic MR imaging correlates more closely with quantitative coronary angiography results than does stress enhancement at SPECT.     

Bronchial to coronary artery fistulas: an important sign of silent coronary artery disease and potential complication during bronchial artery embolization

Coronary artery fistulas are rare and usually asymptomatic congenital anomalies generally diagnosed incidentally during coronary angiographies. Herein, we present a case of bronchial to coronary artery fistula which was diagnosed incidentally during bronchial artery embolization. Embolization was performed successfully without complication, and an underlying important coronary artery stenosis was subsequently found by coronary computed tomography angiography.     

Coronary to pulmonary artery fistula associated with significant coronary atherosclerosis and severe aortic valve stenosis: A Case Report

Coronary artery fistulas are anomalous connections between one or two coronary arteries with either a cardiac chamber or any major blood vessels (coronary sinus, superior vena cava, pulmonary veins and pulmonary artery). It is rarely reported, occurring only in 0.1%-0.2% of patients who undergo coronary angiography. We report a very rare case where myocardial ischaemia may have resulted from the presence of coronary artery fistula, significant coronary artery stenosis and severe aortic valve stenosis. Transthoracic echocardiography showed severe aortic stenosis, while coronary angiography showed a tortuous coronary artery fistula originating from the proximal left anterior descending artery, with a single opening in the main pulmonary artery. Angiography also showed significant stenosis in the middle of the left anterior descending artery. Coronary artery fistula with concomitant significant coronary atherosclerosis and severe aortic stenosis requires optimal therapeutic planning.     

Coronary CTA assessment of coronary anomalies

Coronary anomalies occur in <1% of the general population and can range from a benign incidental finding to the cause of sudden cardiac death. The coronary anomalies are classified here according to the traditional grouping into those of origin and course, intrinsic arterial anatomy, and termination. Classic coronary anomalies of origin and course include those in which a coronary artery originates from the contralateral aortic sinus or the pulmonary artery with anomalous course. Single coronary artery anomalies, in which single coronary artery branches to supply the entire coronary tree, are also included in this category. Anomalies of intrinsic arterial anatomy are a broad class that includes myocardial bridges, coronary ectasia and aneurysms, subendocardial coursing arteries, and coronary artery duplication. Coronary anomalies of termination are those in which a coronary artery terminates in a fistulous connection to a great vessel or cardiac chamber. In the case of those anomalies associated with a risk of sudden cardiac death, the relevant imaging features on CT angiography (CTA) associated with poorer prognosis are reviewed. Recent guidelines and appropriateness criteria favor the use of coronary CTA for the evaluation of coronary anomalies. Although invasive angiography has historically been used to diagnose coronary anomalies, multidetector CT imaging techniques have now become an accurate noninvasive alternative. Cardiac CTA provides excellent spatial and temporal resolution, allowing accurate anatomical assessment of these anomalies.     

Unusual fistulas and connections in the cardiovascular system: A pictorial review

A fistula is an abnormal vascular connection leading to diversion of blood from a high resistance arterial circuit to low resistance venous circuit. Coronary artery fistulas are abnormal communications of the coronary artery with a chamber of the heart, or with any segment of systemic or pulmonary circulation, bypassing the myocardial capillaries. Other unusual fistulas include connection between aorta and the right atrium/superior vena cava, aorta and the inferior vena cava or between a coronary artery bypass graft and a cardiac vein. Abnormal connections also include origin of the coronary artery from the pulmonary artery. In this article, we review the imaging, particularly computed tomography and magnetic resonance imaging of unusual fistulas and connections involving the cardiovascular system, particularly the coronary arteries and the aorta.     

Coronary artery anomalies diagnosed by magnetic resonance angiography

Coronary artery anomalies are uncommon entities that may be associated with sudden death. Because of its 2-D projection imaging nature, conventional X-ray coronary angiography may not accurately delineate the origins and course of aberrant coronary arteries with respect to the great vessels. Non-invasive, cross-sectional imaging techniques such as coronary CT angiography and magnetic resonance angiography are increasingly used in clinical practice to diagnose coronary artery anomalies. Although this study reviews coronary artery anatomy and selected anomalies as seen with true fast imaging with steady-state precession magnetic resonance angiography, the information provided is equally applicable to electrocardiogram-gated coronary CT angiography.     

Coronary MR angiography

MR angiography of the coronary arteries became possible in 1991 with the development of a new group of fast MR imaging sequences. Although the role of coronary MR angiography in screening for coronary artery lesions has not yet been established, coronary MR angiography already has been very successful in the detection of coronary artery variants and the imaging of coronary stents and bypass grafts. Variants of these new MR imaging techniques also can quantitate velocity in native coronary arteries. Several generations of coronary MR angiographic techniques exist; all techniques use EKG-triggering. The use of MR contrast agents appears to further improve all techniques. Technical progress and changes in this subfield of cardiac MR imaging have been so fast that large-scale preclinical trials have not been conducted with the majority of the first and second generation coronary MR angiographic pulse sequences as known today. This article reviews the development of these new cardiac MR imaging techniques and the initial successes with clinical application using commercial MR scanners.     

Noninvasive evaluation of a fistula between a giant coronary aneurysm and coronary sinus performed via multidetector row computed tomography

Coronary artery fistula (CAF) is an uncommon anomaly of congenital and rarely iatrogenic etiology. Most of the patients are asymptomatic, and the anomaly is incidentally recognized during a coronary angiography performed for other reasons. Also, coronary artery aneurysms are rare. We report a case of CAF associated with a giant aneurysm evaluated using multidetector row computed tomography.