Origin of anterior descending coronary artery from right aortic sinus. Intramyocardial tunneling to left side of heart

We report a rare case of a coronary anomaly. All of the coronary arteries originated from a single ostium located in the right coronary cusp. The single coronary artery had a main branch corresponding to the usually dominant right coronary artery. The left anterior descending coronary artery arose from the right coronary artery and coursed intramyocardially within the right ventricular outflow tract to the anterior interventricular sulcus. The absence of evidence of myocardial ischemia in our patient, both clinically and at autopsy, and in three cases reported previously, suggests that the condition reported here was an unlikely cause of myocardial ischemia.     

先天性左冠状动脉主干闭锁3例超声心动图特征及文献复习

目的 通过研究先天性左冠状动脉主干闭锁（LMCAA）的超声心动图表现,提高对LMCAA诊断的准确性.方法 回顾性分析经冠状动脉造影证实的3例LMCAA患儿的超声心动图检查结果,并复习相关文献,总结LMCAA超声心动图特征.结果 LMCAA特异性超声心动图特征：①主动脉左冠状动脉窦内无左冠状动脉主干开口,左冠状动脉主干近心端闭锁呈盲端,远心端内径细窄,发育不良;②右冠状动脉内径增宽;③多切面未显示左冠状动脉与肺动脉确切连接的证据.LMCAA非特异性超声心动图特征：①左心室明显扩大,左室收缩功能可正常或减低;②二尖瓣腱索、乳头肌回声显著增强,可伴有二尖瓣脱垂.彩色多普勒超声特征：①收缩期二尖瓣口可见中至大量反流信号;②左、右冠状动脉之间形成细小侧支循环; ③左冠状动脉前降支和回旋支血流为逆向灌注（向心性）;④发育不良的左冠状动脉虽然在肺动脉周围分布,但彩色多普勒超声不能显示其与肺动脉连接的确切逆灌血流信号.结论 LMCAA有特异性的超声心动图特征,提高对LMCAA的全面认识是诊断本病的关键.     

Length of left main coronary artery. Lack of correlation to coronary artery dominance and bicuspid aortic valve: an autopsy study of 54 cases

Previous coronary angiographic data have suggested that the left main length of the coronary artery correlated with dominance (origin of the posterior descending branch) and bicuspid aortic valves. In our autopsy study with direct measurements of left main lengths, 41 patients with tricuspid aortic valves and 13 with bicuspid aortic valves were examined for right, left, or codominance. There was no statistically significant difference in either coronary dominance or the length of left main coronary artery between the congenital bicuspid and tricuspid aortic valves. Age, sex, heart weight, extent of coronary artery disease, left ventricular wall thickness, and site of prior infarction did not correlate with left main length or dominance. Thus, short left main lengths do not correlate with coronary dominance or with aortic valves. Angiographic assessment of left main coronary artery length is subject to magnification, oblique projection, and catheter position errors.     

Unexpected sudden death of a 19-year-old female with congenital single coronary artery ostium during exertion

Coronary artery anomalies are associated often with myocardial ischemia or sudden cardiac death. A 19-year-old woman who participated in an exertive game lost consciousness upon one such exertion. She was taken to a hospital where she died on the same day. An autopsy revealed that she had bifurcated coronary arteries, which arose from one coronary ostium in the left sinus of Valsalva. The right coronary artery arose from the left sinus and traveled between the aorta and the pulmonary trunk. The heart as well as the cardiac conduction system depended exclusively on the single coronary artery ostium for oxygenated blood supply, and the unbalanced blood distribution on her exertion probably led to sudden cardiac death. The case highlights the medicolegal importance of unexpected sudden cardiac death related to an anomalous origin of the coronary arteries.     

Coronary thromboembolism with fatal outcome following coronary angiography

A case of fatal thromboembolic occlusion of the left coronary artery at selective coronary arteriography is described. The course of events and the findings at autopsy suggest that thrombotic material was deposited on one intravascular catheter and transferred to a second catheter inserted over the same guide wire. Contrast injection through the second catheter into the left coronary ostium resulted in immediate and fatal occlusion of the two major branches of the left coronary artery.     

Prevalence of left and balanced coronary arterial dominance decreases with increasing age of patients at autopsy. A postmortem coronary angiograms study

BackgroundIn patients presenting with an acute coronary syndrome, left over right coronary dominance appears to be independently associated with increased long-term mortality. This could lead to decreasing numbers of patients with a left dominant coronary artery system in older age groups.MethodsWe assessed the type of coronary dominance in different age groups in postmortem angiograms that were routinely performed at autopsy between 1993 and 2007. Coronary dominance was determined by identifying the origin of the posterior descending artery and posterolateral branches on postmortem angiography. Age, gender, and cause of death were recorded from the autopsy database. The prevalence of left dominant, right dominant, and codominant systems was determined in three increasing age categories, with cutoffs based on tertiles.ResultsA total 1620 coronary angiograms were assessed; 167 were excluded because it was not possible to determine coronary dominance. The median age of all patients was 71 years; 56% were male. Of all deaths, 40% were classified as cardiac. Regarding coronary dominance, 81.2% was right, 9.1% was left, and 9.7% was codominant. Overall, a decrease in prevalence of left and codominant coronary systems was observed with increasing age in the three age cohorts (≤63years, 64–75 years, and ≥76 years) (P=.001 for overall comparison).ConclusionsIn this large autopsy cohort, the prevalence of a left dominant or codominant coronary system decreased with increasing age. These findings could relate to a slightly higher risk of mortality in case of left versus right coronary artery occlusion.     

Two adult cases of congenital atresia of the left coronary ostium—comparison of a sudden death case with a long-term survival case

We present two extremely rare autopsy cases with atresia of the left coronary ostium. Case 1 was a 34-year-old man who died of sudden cardiac causes with localized acute subendocardial infarction and Case 2 was an 82-year-old woman who died from non-cardiac causes. In both cases, a string-like small left main trunk that was located in its normal position was found; however, the orifice of the left coronary artery was absent in both cases. The collateral artery (CA), whose caliber was smaller than that of the proximal left descending artery (LAD), arose from the right coronary sinus and was anastomosed with the distal LAD. However, it was only in Case 1 that the CA showed an acute angle of take-off from the aorta, subsequently coursing between the root of the aorta and the pulmonary trunk, with possible mechanical compression by these two arteries. These two cases suggest that atresia of the left coronary ostium is developmentally and anatomically different from single coronary artery or left coronary artery arising from the opposite sinus of valsalva. Atresia of the left coronary ostium is considered to be an important differential diagnosis as a cause of sudden death, not only in the pediatric population but also in adults. The caliber and/or other anatomical features of the CA may predominantly dictate the clinical course of patients with atresia of the left coronary ostium.     

左冠脉主干和三大主粥样硬化与心机梗塞的对比调查（附128例尸检分析）

对128例心肌梗塞尸检进行了分析，其中60岁以上92例（71．9％）、59岁以下36例（28．1％），左冠脉主干动脉粥样硬化（As）Ⅳ级共21例（16．4％），年龄在60岁以上仅有15例（11．7％），59岁以下6例94．7％）。但在前降支AsⅣ级有106例（82．8％），左旋支71例（55．5％），右冠脉主干88例（68．7％），说明左主干AsⅣ级狭窄明显轻于三大主支。左主干AsⅣ级狭窄的出现也较三大主支为晚。左主干AsⅣ级狭窄发生陈旧性透壁心肌梗塞多于急性透壁性心肌梗塞，其心肌梗塞范围也较广泛。左主干As狭窄程度与心肌梗塞并发症的产生虽无直接相关，但有加重作用。左主干无1例在As基础上并发新鲜血栓，而三大主支并发血栓有66例（51．6％）。     

Right coronary ostium agenesis with absence of the right coronary artery: a rare case of non-ST elevation coronary syndrome

We present a case with right coronary ostium agenesis with anomalous origin of the right coronary artery from the left circumflex artery, which caused a non-ST elevation coronary syndrome. A review of the literature indicates this to be an extremely rare case.     

Evidence at autopsy of spasm in the distal right coronary artery in persons with coronary heart disease dying suddenly

The aim of this study was to examine whether there are morphological signs in spasm in the coronary arteries at autopsy in persons with coronary artery disease dying suddenly. From a forensic autopsy service, 48 cases of sudden and unexpected deaths were selected: 24 cases with a preliminary diagnosis of coronary heart disease and 24 cases involving persons dying of noncoronary causes. A complete autopsy according to a preset protocol was followed with particular emphasis on the heart examination. The myocardium and the coronary arteries were sampled and examined without knowledge to which group the case belonged. The degree of folding of the internal elastic lamina of the proximal and distal parts of the coronary arteries was measured by picture analysis of elastin-stained cross sections of the arteries. The degree of folding was significantly greater in the distal section of the right coronary artery in cases of the coronary group compared to the folding in the same section in cases of the noncoronary group. In the proximal part of the right coronary artery and in the left coronary artery with its two branches, there were no differences in the folding of the internal elastic membrane between the groups.

Our findings indicate that a spasmic contracture of an artery may be diagnosed postmortem. The spasm of the distal part of the right coronary artery may have caused focal ischemia in the central parts of the cardiac conducting system, precipitating a lethal arrhythmia.     

Total anomalous origin of the coronary circulation from the right pulmonary artery

Origin of both coronary arteries from a branch of the pulmonary artery is rare and has not been reported as a cause of sudden unexpected death. We report autopsy findings of a 14-day male infant in previously good health who died suddenly. From the proximal right pulmonary artery arose a single coronary artery, which branched into the right and left main coronary arteries. The right proximal coronary artery coursed between the aorta and pulmonary trunk, and the left main traveled along the anterior proximal aorta. The distal course of the coronary circulation was normal. There was concentric subendocardial healing myocardial infarction. No other congenital anomalies were identified. Total anomalous origin of the coronary arteries from the pulmonary trunk or artery should be considered in cases of sudden unexpected death in infants.     

Single coronary artery arising from the right sinus of Valsalva (case report)

A single coronary artery is a rare congenital anomaly of the coronary arteries where only one coronary artery arises from the aortic trunk by a single coronary ostium, supplying the entire heart. We report a case of a 70 years-old man with mitral valvular insufficiency and atherosclerotic right and left circumflex coronary arteries, in whom coronary angiography showed a single coronary artery arising from a single ostium in the right sinus of Valsalva (R-II-B subtype) and transverse trunk coursed between aorta and pulmonary artery. The clinical significance and subtype of the single coronary artery are discussed.     

Massive acute infarction of the right ventricular wall without or only minimal infarction of the left ventricular wall after aortic valve replacement with or without simultaneous replacement of the ascending aorta

Certain clinical and cardiac morphologic findings are presented in two men who developed massive right ventricular (RV) infarction with only minimal or no left ventricular infarction early after aortic valve replacement. The ostium of the right coronary artery was severely narrowed in one patient by the ring of the bioprosthesis, and in the other patient the right coronary artery was completely severed at the time of valve replacement without insertion of a coronary bypass conduit. Such massive infarction of the RV free wall has not been reported previously.     

Ectopic origin of coronary arteries from the aorta in Syrian hamsters (Mesocricetus auratus)

An ectopic origin of the coronary artery from the aorta beyond the sinotubular junction, a condition commonly referred to as 'coronary artery high take-off', has been described in man and C57BL/6 mice. The present paper reports this congenital coronary artery anomaly in the Syrian hamster (Mesocricetus auratus). Hearts from 14 individuals, aged 53-350 days, were examined by means of a corrosion-cast technique, scanning electron microscopy or histological and immunohistochemical techniques. In 11 hamsters, the right coronary artery was the ectopic vessel. In the other three animals there was a solitary coronary ostium in the aorta. In all cases, the ectopic coronary artery originated at an acute angle and a valve-like ridge was in front of the coronary artery ostium. The ectopic arteries examined microscopically showed an intramural trajectory within the aortic wall. In the hearts with a solitary ostium in the aorta, the left main coronary artery coursed between the aorta and the pulmonary artery. In man, all of these anomalous conditions place the individual at risk of myocardial ischaemia and sudden death. However, none of the affected hamsters had clinical signs of disease. Intimal thickenings of increasing size with age were present in the intramural coronary artery segment of eight hamsters aged 106 days or older, examined histologically. The present findings fit with the notion that coronary arteries with acute angle take-off and an intramural course are subjected to unusual wear and tear, leading to tissue changes in the vessel wall.     

The positions of coronary arterial ostia

The positions of the coronary arterial ostia were examined in the cadavers of 38 adults. All the ostia were related to the aorta and none to the pulmonary artery. The aortic valves in 37 specimens were normal and possessed three cusps, while one was bicuspid. In the normal specimens, the main right and left coronary ostia were confined to the anterior and left posterior aortic sinuses respectively, apart from one specimen in which the right ostium was related to the right posterior sinus. Six specimens had small accessory ostia, close to the main right ostium. The majority of ostia were situated on or immediately below the supravalvular ridge. Circumferentially, the ostia clustered near the maximum curvature of the sinus. In the single specimen where the aortic valve was bicuspid, both ostia lay more-or-less symmetrically in the sinus above an anterior cusp which showed evidence of formation from two components. The reasons for confinement of the coronary ostia to only two of the three aortic sinuses are not clear. Microscopic examination of serial sections through 22 human embryos of 5.0–17.5 mm CR length (Carnegie stages XIII–XIX) confirmed that the earliest vessels in the heart wall develop subepicardially near the apex at stage XV. The network extends centripetally and only at stage XVII could coronary arterial stems, communicating with the aortic lumen, be identified. The sequence suggests that confinement of the coronary ostia to the anterior and left posterior sinuses probably occurs because these represent the most accessible contact points for the centripetally growing vascular plexus. © 1996 Wiley-Liss, Inc.     

Autoregulation by the right coronary artery in dogs with open chests; comparison with the left coronary artery

Experiments were conducted to study autoregulatory responses of the right and left coronary arteries in dogs with open chests. The right and left circumflex coronary artery were cannulated and perfused with blood from the femoral artery via a pressurized reservoir. The perfusion pressure was varied in steps over a wide range and coronary blood flow rates were measured. Both the right and left coronary arteries exhibited autoregulation but the pressure at the lower end of the autoregulatory range was lower in the right (39.8±9.1 mm Hg) than in the left circumflex coronary artery (57.6±14.5 mm Hg). The slope of the pressure-flow relationship in the autoregulatory range was less steep in the right than the left circumflex coronary artery. The closed-loop gain when the perfusion pressure was less than 100 mm Hg was greater in the right than in the left circumflex coronary artery. Increases in the right ventricular afterload produced by pulmonary artery constriction decreased the closed-loop gain, shifted the autoregulatory range upward and to the right, and made the slope steeper. These results indicate that more effective autoregulation is carried out by the right than the left circumflex coronary artery.     

Ectopic "high" origin of both coronary arteries from the left aortic wall: anatomic and postmortem angiographic findings

Anatomic and postmortem angiographic findings of a previously unreported case of ectopic origins and unusual courses of the right coronary (RC) artery and the left coronary (LC) artery were demonstrated. This specimen was unique among 450 angiographies and 60 corrosion castings of the human hearts examined in this study. The ostium of the RC artery was pocket-like, located in the left aortic wall at roughly 180 degrees to the long axis of the ascending aorta and 19 mm above the rim of the sinotubular junction (SJ). Initially, the RC runs to the right and downward, passing high in the cleft between the aorta and the pulmonary trunk, thereby avoiding a possible compression from them. The ostium of the LC faced upward and originated from the left aortic wall 7 mm above the SJ. The LC ran to the left and downwards for 16 mm until its division. Histologically, the first 11 mm of the RC were elastic. This observation, together with its high course between the great vessels, combined to make this case benign. The best x-ray projections to show the characteristic findings of the present case were anteroposterior and lateral, which were of practical importance for the correct determination and interpretation of this case. The cardiac surgeon should be aware that high cannulation will be required to locate the RC to avoid accidentally cross-clamping or transecting the vessel during surgery where this anomaly may be encountered.     

Ectopic "high" origin of both coronary arteries from the left aortic wall: anatomic and postmortem angiographic findings

Anatomic and postmortem angiographic findings of a previously unreported case of ectopic origins and unusual courses of the right coronary (RC) artery and the left coronary (LC) artery were demonstrated. This specimen was unique among 450 angiographies and 60 corrosion castings of the human hearts examined in this study. The ostium of the RC artery was pocket-like, located in the left aortic wall at roughly 180 degrees to the long axis of the ascending aorta and 19 mm above the rim of the sinotubular junction (SJ). Initially, the RC runs to the right and downward, passing high in the cleft between the aorta and the pulmonary trunk, thereby avoiding a possible compression from them. The ostium of the LC faced upward and originated from the left aortic wall 7 mm above the SJ. The LC ran to the left and downwards for 16 mm until its division. Histologically, the first 11 mm of the RC were elastic. This observation, together with its high course between the great vessels, combined to make this case benign. The best x-ray projections to show the characteristic findings of the present case were anteroposterior and lateral, which were of practical importance for the correct determination and interpretation of this case. The cardiac surgeon should be aware that high cannulation will be required to locate the RC to avoid accidentally cross-clamping or transecting the vessel during surgery where this anomaly may be encountered.     

Relationship between heart weight and the cross sectional area of the coronary ostia.

Sex variation in the area of the coronary ostia was studied in hearts with a normal weight (heart weight less than 400 g) and hypertrophic hearts (heart weight greater than or equal to 400 g). Also studied was a possible sex difference in the correlation between heart weight and the area of the coronary ostia. The study was performed on 379 post mortem hearts. In the group of hearts with a normal weight the area of the left coronary ostium in both sexes was greater than the right but the difference was statistically insignificant. There was no sex difference in the area of the left coronary ostium, whereas the area of the right coronary ostium was statistically significantly less in women. In the group of hyperthopic hearts the left coronary ostium increased in area with increasing heart weight. The difference in the area of the left coronary ostium between hearts with normal weight and hypertrophic hearts was stastically significant in men, but not in women. The right coronary ostium showed minimal increase in size with increasing heart weight and the difference in both sexes between the two groups was statistically insignificant. In the group of hypertrophic hearts the heart weight was best correlated to the area of the left coronary ostium in both sexes, but the values did not reach statistically significance. On the basis of this study the area of the right coronary ostium appears to be a bottleneck with regard to an adequate blood supply to a hypertrophic myocardium.     

Anatomical study of a left single coronary artery with special reference to the various distribution patterns of bilateral coronary arteries

A left single coronary artery of heart was observed during anatomy practice at Kumamoto University School of Medicine in a 73-year-old female cadaver who died from a thalamic hemorrhage. The left single coronary artery, having a single orifice in the left aortic sinus, bifurcated into the anterior interventricular (IVa) and circumflex (CIR) arteries. No orifice of the right coronary artery was found on the aortic wall. Giving off a branch which traversed the upper part of the infundibulum to supply the anterior upper region of the right ventricle, the IVa descended in the anterior interventricular sulcus to supply the apex of the heart. The CIR curved leftwards in the atrioventricular sulcus to reach the posterior surface, after which it continued to emerge again into the anterior surface. The atrial arteries showed no anomalous distribution pattern and histological observation revealed no pathological abnormality other than a slightly thickened tunica intima. Furthermore, we observed the distribution patterns of bilateral coronary arteries in 377 hearts dissected during anatomical practice over 13 years at Kanazawa University (1980–1986) and Kumamoto University (1993–1998). Although the reason why only the right coronary artery was absent is left unexplained, it was concluded that the left single coronary artery in this study, having the developed left conal and circumflex branches, was an extreme case of the left dominant series of coronary arteries. The formation of single coronary arteries can be explained embryologically by the change of flow in the capillary plexus established on the ventricle wall.