Coronary artery anomalies--current clinical issues: definitions, classification, incidence, clinical relevance, and treatment guidelines.
ABSTRACT The study of coronary artery anomalies would benefit from the clarification of various fundamental issues, including the definitions, classification, incidence, pathophysiologic mechanisms, and clinical relevance of each anomaly. The greatest challenge is to identify the abnormality and determine its clinical relevance so that appropriate treatment can be instituted. Currently, the coronary anatomy is essentially defined by the features of the (conductive) epicardial coronary tree and its dependent territory. Therefore, one must consider all the possible and observed variations in anatomic features that are used to describe the coronary arteries. We propose that the left anterior descending, circumflex, and right coronary arteries be considered the essential elementary units of coronary anatomy. We also suggest that the coronary arteries be defined not by their origin or proximal course, but by their intermediate and distal segments or dependent microvascular bed. A strict classification system is necessary before meaningful data can be gathered about the incidence of coronary anomalies. With respect to clinical relevance, the greatest challenge is presented by anomalies that only occasionally cause critically severe clinical events and are otherwise compatible with a normal life. In such cases, it is not known whether the specific features of a given anomaly cause adverse clinical consequences, or whether additional episodic factors are required. To correlate subclassifiable anatomic and functional features with clinical events and prognoses, a large, multicenter database, relying on prospective, coordinated protocols, is urgently needed. In the absence of established official guidelines, we present practical protocols for diagnosing and treating coronary anomalies.
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ABSTRACT: The purpose of this study was to evaluate functional variables and morphologic correlates of chronically hypoperfused myocardium before and after revascularization. Neonates with congenital anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA syndrome) develop some myocardial necrosis shortly after birth. The survivors of this event are left with a localized infarction and an almost entirely collateral circulation-dependent perfusion of the left ventricle that results in poor global left ventricular function. Survival beyond infancy is uncommon because of severe left heart failure. Revascularization, however, brings about functional recovery with good clinical outcome. The ALCAPA syndrome is thus characterized by chronic collateral circulation-dependent low perfusion, low contraction matching and potential revivability. Five patients with ALCAPA syndrome are presented, with preoperative and postoperative clinical findings and histologic data obtained from intraoperative transmural biopsy specimens. The angiographically assessed preoperative ejection fraction was 33 +/- 19% (mean +/- SD). Postoperative echocardiographic follow-up revealed normal left ventricular function in all patients. Histologic study of the biopsy specimens taken from the region perfused by the anomalous artery showed a variable degree of fibrosis (51 +/- 32%). The ultrastructure of the remaining myocytes revealed viable characteristics, but a substantial percent (46 +/- 26%) showed a markedly reduced fraction of contractile material. These ultrastructural studies suggest delayed subcellular adaptive responses in the chronically hypoperfused myocardium of patients with ALCAPA syndrome.Journal of the American College of Cardiology 04/1994; 23(3):772-8. · 14.09 Impact Factor
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ABSTRACT: We sought to prospectively determine the incidence and clinical significance of major coronary artery anomalies in asymptomatic children using transthoracic two-dimensional echocardiography. Anomalous origins of the left main coronary artery (ALMCA) from the right sinus of Valsalva or anomalous origins the right coronary artery (ARCA) from the left sinus are rarely diagnosed in children and can cause sudden death, especially in young athletes. Because most patients are asymptomatic, the diagnosis is often made post mortem. No study to date has prospectively identified anomalous coronary arteries in asymptomatic children in the general population. After serendipitously identifying an index case with ALMCA, we examined proximal coronary artery anatomy in children with otherwise anatomically normal hearts who were referred for echocardiography. In those diagnosed with ALMCA or ARCA, we performed further tests. Within a three-year period, echocardiograms were obtained in 2,388 children and adolescents. Four children (0.17%) were identified with anomalous origin of their coronary arteries, and angiograms, exercise perfusion studies and/or stress tests were then performed. One ARCA patient had decreased perfusion in the right coronary artery (RCA) perfusion area and showed ventricular ectopy on electrocardiogram (ECG) at rest that diminished but did not resolve with exercise. A second patient with ALMCA had atrial tachycardia immediately after exercise, with inferior and lateral ischemic changes on ECG and frequent junctional and/or ventricular premature complexes both at rest and recovery. This study demonstrates that although anomalous origins of coronary arteries are rare in asymptomatic children, the prevalence is greater than that found in other prospective studies. Ischemia can occur with both ALMCA and ARCA even though patients remain asymptomatic. Because of the high risk of sudden cardiac death, aggressive surgical management and close follow-up are necessary.Journal of the American College of Cardiology 03/2001; 37(2):593-7. · 14.09 Impact Factor
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ABSTRACT: Congenital coronary anomalies are associated with sudden death and exercise-related death. Clarification of the risk and mechanisms of sudden death in patients with coronary anomalies may aid in decisions on intervention. The clinicopathologic records of 242 patients with isolated coronary artery anomalies were reviewed for information on mode of death and abnormalities of the initial segment (acute angle takeoff, valvelike ridges or aortic intramural segments) and course of the anomalous coronary artery. Cardiac death occurred in 142 patients (59%); 78 (32%) of these deaths occurred suddenly. Of sudden deaths, 45% occurred with exercise. Sudden death (28 of 49, 57%) and exercise-related death (18 of 28, 64%) were most common with origin of the left main coronary artery from the right coronary sinus. Anomalous origin of the right coronary artery from the left coronary sinus was also commonly associated with exercise-related sudden death (6 of 13 sudden deaths, 46%). High risk anatomy involved abnormalities of the initial coronary artery segment or coursing of the anomalous artery between the pulmonary artery and aorta. Younger patients (less than or equal to 30 years old) were significantly more likely than older patients (greater than or equal to 30 years old) to die suddenly (62% vs. 12%, p = 0.0001) or during exercise (40% vs. 2%, p = 0.00001) despite their low frequency of significant atherosclerotic coronary artery disease (1% vs. 40%, p = 0.00001). Younger patients (less than or equal to 30 years old) with an isolated coronary artery anomaly are at risk of dying suddenly and with exercise. Therefore, greater effort for early detection and surgical repair of these lesions is warranted.Journal of the American College of Cardiology 10/1992; 20(3):640-7. · 14.09 Impact Factor