A case of anomalous bronchial artery ramified from coronary artery

There have been no anatomical reports on the origin of the bronchial artery derived from the coronary artery. In a 2006 cadaveric dissection course, an anomalous bronchial artery that reached the middle lobe of the right lung from the left coronary artery was observed in an 88-year-old Japanese man. In this specimen, the circumflex branch of the left coronary artery passed under the left auricle in the coronary sulcus and bifurcated to three branches (left marginal branch, posterior left ventricular branch, atrial branch), which were 3.2–3.4 mm in diameter. The atrial branch intersected on the surface of the great cardiac vein, ran along the oblique vein of the left atrium, and reached the atrial side of the transverse pericardial sinus, and then divided into two branches. One of them led to the right atrium. The other branch passed between two right superior pulmonary veins, which derived from superior and middle lobes of the right lung, respectively, through the hilum of the lung along the right superior pulmonary vein derived from the middle lobe, and finally became the bronchial artery in the middle lobe of the right lung. In the middle lobe, the bronchial artery divided into a thin branch along the pulmonary vein for the lateral segment, ran along the surface of the right middle bronchus, and then reached the medial segment, being wedged between the segmental bronchus and vein.     

The relationship of myocardial bridges to coronary artery dominance in the adult human heart

Myocardial bridging is recognized as an anatomical variation of the human coronary circulation in which an epicardial artery lies in the myocardium for part of its course. Thus, the vessel is 'bridged' by myocardium. The anterior interventricular branch of the left coronary artery has been reported as the most common site of myocardial bridges but other locations have been reported. The purpose of this study was to provide more definitive information on the vessels with myocardial bridges, the length and depth of the bridged segment, and the relationship between the presence of bridges and coronary dominance. Two hundred formalin-fixed human hearts were examined. Myocardial bridges were found in 69 (34.5%) of the hearts with a total of 81 bridges. One bridge was found in 59 of these hearts and multiple bridges were observed in ten (eight with double bridges and two with triple bridges). Bridges were most often found over the anterior interventricular artery (35 hearts). Bridges were also found over the diagonal branch of the left coronary artery (14), over the left marginal branch (five) and over the inferior interventricular branch of the left coronary artery (six). Bridges were also found over the right coronary artery (15 hearts), over the right marginal branch (four) and over the inferior interventricular branch of the right coronary artery (two). The presence of bridges appeared to be related to coronary dominance, especially in the left coronary circulation. Forty-six (66.6%) of the hearts with bridges were left dominant. Forty-two of these had bridges over the left coronary circulation and four over the right coronary circulation. Seventeen hearts (24.6%) were right dominant. Eleven of these had bridges over the right coronary circulation and six over the left coronary circulation. The remaining six hearts were co-dominant with four having bridges over the left coronary circulation and two over the right coronary circulation. The mean length of the bridges was 31 mm and the mean depth was 12 mm. The possible clinical implications of myocardial bridging may vary from protection against atherosclerosis to systolic vessel compression and resultant myocardial ischaemia.     

Variation in length and termination of the ramus circumflexus of the human left coronary artery

The length and termination of the circumflex branch of the left coronary artery were studied in 81 hearts, after injection of the coloured substance containing a radiopaque medium. The hearts were radiographed, dissected, drawn and photographed. The short type of circumflex branch, defined as a branch that did not reach the crux cordis, was found to be much more frequent (86.4%) than the long type and terminated in the majority of the cases (76.5%) as one of the posterior branches of the left ventricle.     

A Study of Coronary Dominance in the Population of Assam

With the ever increasing load of coronary heart disease, an in-depth study of the coronary arteries has been felt by the medical fraternity. Coronary arteries show wide variations among different populations. These region based variations have not been dealt with enough in the standard books. The knowledge of these variations are of paramount importance when considering various surgical interventions. This study therefore aims to focus on the pattern of coronary dominance in Assam which is ethnically unique from the rest of India. Seventy cadaveric hearts were studied. The population under study included the population of Assam. The coronary arteries were examined by gross dissection and analyzed statistically. The modes of termination of the right coronary artery and the circumflex artery were described with the help of five points: at the right border, between the right border and the crux, at the crux, between the crux and the left border and at the left border. Origin of the posterior interventricular artery was taken as the basis of dominance. Right dominance was found in 70%, left dominance was found in 18.57% while balanced pattern was observed in 11.43% hearts. The results of the study were compared with other authors and variations were noted.     

Narrowed lumen of the right coronary artery in chronic Chagasic patients is associated with ischemic lesions of segmental thinnings of ventricles

Thinning of myocardial segments, mainly at the apex and basal posterior region of left ventricle, are frequent lesions in chronic chagasic cardiopathy (CCC), but still without a well determined etiology. Previously we found severe myocardial microvascular dilatation that could cause ischemia in watershed regions. In this study we analyzed whether narrowness in epicardial coronary arteries in CCC might explain these thinned ventricular lesions. Two groups of dilated hearts with similar weights were compared: eleven hearts from patients with CCC versus four hearts from patients with dilated cardiomyopathy (IDCM). As normal controls we studied three non dilated normal weight hearts. There were no atherosclerotic plaques in the main branches of epicardial coronary arteries and cross-sectional luminal areas of proximal and distal segments were histologically measured. It was found that CCC hearts presented a lower mean luminal area in the right coronary artery (RCA) branch than IDCM, in proximal (4.3 +/- 1.4 vs 6.6 +/- 2.0 mm2; p=0.02) and in distal (1.6 +/- 1.0 vs 3.4 +/- 0.9 mm2; p=0.01) segments, with no statistical differences with normal hearts (2.7 +/- 1.3 and 1.5 +/- 0.3 mm2) in proximal (p=0.2) and distal (p=0.11) sections. In conclusion thinning of ventricular wall in CCC patients seems to be ischemic lesions in the peripheral territory irrigated by the right coronary artery, possibly due to a steal phenomenon by the left coronary, induced by micro vessels dilatation.     

Anomalous first septal perforator artery: Anatomic-clinical correlates

The interventricular septum is considered the most densely vascularized portion of the heart, containing important elements of the cardiac conduction system and providing mechanical support for both right and left ventricular function. Anatomically, this structure is perfused by the relatively small caliber anterior and posterior septal perforator branches arising from two large epicardial coronary vessels, the anterior interventricular (descending) branch of the left coronary artery and the posterior interventricular (descending) branch of the right coronary artery, respectively. In cases of significant atherosclerotic disease depriving flow in the major coronary vessels and their septal branches, an anomalous septal perforator artery can take over the task of supporting the function of the interventricular septum by supplementing essential collateral flow. © 1996 Wiley-Liss, Inc.     

The anatomy of the coronary sinus and its tributaries

The coronary sinus and its tributaries were studied by anatomical dissection in 37 adult human cadaveric hearts, which had been fixed in formalin solution. An anastomosis of approximately 1.0mm in calibre was observed between the anterior and posterior interventricular veins in 19% of specimens. Myocardial bridges were detected above the anterior interventricular vein or its tributaries in 8% of specimens. The great cardiac vein formed the base of the arteriovenous trigone of Brocq and Mouchet with the bifurcating branches of the left coronary artery in 89% of specimens and formed an angle accompanying these arterial branches in 11%. In the trigone the anterior interventricular and great cardiac veins were superficial to the arteries in 73% of specimens. The left marginal vein was present in 97% of specimens, emptying into the great cardiac vein in 81% of cases and into the coronary sinus in the remaining 19%. The small cardiac vein was present in 54% of specimens. In the coronary sulcus the great cardiac vein was adjacent to the circumflex branch of the left coronary artery in 76% of specimens and to the right coronary artery in 5% in 19% there was no relationship with either artery. The coronary sinus maintained a relationship with the right coronary artery in 46% of specimens and with the left coronary artery in 32% in 22% it had no relationship with these vessels.     

Posterior right diagonal artery

Background: There is general confusion about a branch of the posterior segment of the right coronary artery that has been referred to as 1) the lower trunk of a divided right coronary artery; 2) a posterior reflection of the right marginal artery; 3) the ramus lateralis; and 4) a posterolateral branch or a posterior descending artery. Materials: Three hundred human hearts were studied by direct observation, X-ray films, and corrosion casting. Results: This branch of the right coronary artery arises either after the right marginal artery (in 84% of hearts) or it constitutes the continuation of this artery in the remaining 16%. We named it the posterior right diagonal artery (PRDA). It was found in 14% of 266 hearts of right dominant type. It was present in 39% when the length of the posterior descending artery (PDA) was shorter than half of the length of the posterior interventricular sulcus (PIS) and in 6% when it was longer. When the PRDA originated directly from the RCA, the RMA appeared underdeveloped; the PRDA always occupied the inferior part of the PIS and appears either as continuation of a short PDA or as a replacement for a long PDA from the point where this artery leaves the PIS to enter the posterior wall of the left ventricle. The PDRA when present serves as a bridge between the RCA and the left anterior descending artery. Conclusions: These findings are of practical importance for the correct interpretation of coronary arteriographies and in the field of coronary artery surgery. © 1994 Wiley-Liss, Inc.     

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.     

Intersection patterns of human coronary veins and arteries

Intersections between the coronary veins (CV) and arteries (CA) of 103 adult human hearts were mapped on the heart surface. Then the correlations of these intersection patterns to their localization were studied. Eight spots were selected where one of four major CV (anterior cardiac vein, middle cardiac vein, left posterior ventricular vein, and great cardiac vein) intersected with one of CA and their branches (right coronary artery, posterior interventricular branch, left posterior ventricular branch, circumflex branch, diagonal branch, and anterior interventricular branch). The great cardiac vein (GCV) ran beneath the anterior interventricular branch in 56 specimens out of 103, beneath the diagonal branch in 75 specimens out of 103, and beneath the circumflex branch in 36 specimens out of 103, while the other CV mostly ran over CA. The present observations suggest that the CV on the right side may be formed prior to CA, while the CV on the left side may be formed simultaneously with CA.     

家猪壁冠状动脉观测及与犬壁冠状动脉比较

目的为壁冠状动脉比较解剖学积累资料，为选择动物模型提供依据。方法家猪心脏塑化染料灌注，10％甲醛溶液固定，大体解剖显示壁冠状动脉，测量数据，并与既往文献报道的犬的壁冠状动脉分析比较。结果家猪壁冠状动脉出现率为50．0％，前室间支、后室间支壁冠状动脉出现率为15．0％、27．5％。前室间支壁冠状动脉近端径（1．96±0．71）mm，远端径（1．52±0．80）mm，长度（9．19±6．58）mm。总壁冠状动脉长度（9．20±4．99）mm。一支血管上可出现1-2处的壁冠状动脉壁。壁冠状动脉可以扭曲和发出细小的分支血管。结论家猪可以作为动物模型研究壁冠状动脉，但犬比家猪更为适合。     

Short left circumflex artery

There was evidence of posterior infarction in 61 of 212 hearts studied. The condition was associated with a relatively short circumflex branch of the left coronary artery (LCX) in 24 hearts and with a longer LCX in 37 hearts. Total occlusion of LCX was found in two (8%) hearts with a shorter circumflex branch and in 27 (73%) hearts with a longer circumflex branch. The right coronary artery (RCA) was occluded in nearly all hearts with posterior infarction. In those hearts with a shorter LCX, occlusion of RCA appeared to be the major factor in the pathogenesis of posterior myocardial infarction.     

Anatomical study on the sinuatrial nodal branch in the human coronary artery

The sinuatrial nodal branch (SANB) of the coronary artery is anatomically important as it irrigates the sinuatrial node. Past studies on the origin and route of the SANB in the human heart have produced discrepant findings. Therefore, in this study, we macroscopically investigated the origin, route, and distribution of the SANB in 293 human hearts. In addition, we examined the relationship between coronary artery dominance and the origin of the SANB. The SANB was found to have one branch in 267 specimens (91.2 %), two branches in 25 specimens (8.5 %), and three branches in one (0.3 %) specimen. The SANB originated from the right coronary artery in 184 branches (57.5 %) and from the left coronary artery (circumflex artery) in 136 branches (42.5 %). Nine SANB routes were classified, all of which were distributed in the interatrial septum except for one heart with a type R3 SANB course, which was found to extend through the muscle layer of the interatrial septum into the septum. The composition of these courses could relate to the generation of the proepicardium in the amniote.     

Myocardial bridges over coronary arteries in Cercopithecus.

The presence of myocardial bridges over the coronary arteries has been studied in 29 monkey (Cercopithecus aethiops) hearts. The great resemblance between the Cercopithecus subepicardial arterial net with the corresponding one in humans has been revealed. There is a high incidence (83%) of myocardial bridges only over the ventricular branches of both coronary arteries. Myocardial bridges are usually (90%) located over the left coronary artery branches, and the left anterior interventricular branch is the most frequently (69%) overbridged vessel. The bridges are always single over the vessel examined and their length varies from 0.5 mm to 31.6 mm. No statistically significant sexual difference in myocardial bridges distribution is reported.     

Anatomy of the coronary arteries in fetal pigs: comparison with human anatomy

In this study, 94 fetal pigs were used to comprehensively investigate the origins, number, location, and distribution of the coronary arteries to enrich knowledge on the coronary circulation in fetal pigs, and allow comparison with adult pigs and humans. In fetal pigs, the posterior interventricular sulcus branch always arose from the right coronary artery and the circumflex artery was rarely extended to the posterior interventricular sulcus, while it is variable in humans. In fetal pigs, there was sometimes anastomosis (8.5%) between the left and right conus branches as nutrient arteries of the pulmonary cone. Other branches were not significantly different between fetal pigs and humans, including the acute marginal branch, obtuse marginal branch, and sinoatrial nodal artery. Coronary dominance was also similar. In conclusion, compared with adult pigs, dissection of the coronary arteries in fetal pigs provided a more faithful overview of the porcine coronary circulation. The coronary arteries in fetal pigs were also more suitable for comparison with humans when pigs are used as experimental animals for studying the coronary vessels, which could be an important reference for investigation of clinical treatment of the coronary arteries. In summary, our data provide reliable information about the distribution and ramifications of the coronary arteries, and could be useful for clinicians and surgeons who wish to comprehensively understand coronary anatomy.     

Functional dominance of the right coronary artery: Incidence in the human heart

After injection of radiopaque medium, 200 human hearts were studied by direct observation and x-ray analysis. The right coronary artery (RC) was dominant in 178 of these hearts as characterized by giving off the typical posterior interventricular artery (PIV), the posterior descending artery. Within this group, 19 specimens had right coronary arteries that gave off both a large posterior interventricular artery (LPIV) and a branch that continued beyond the crux termed a large extension of the right coronary (LERC). The subgroup of hearts supplied thusly was termed real right dominant (RRD). The RC in these hearts supplied the right ventricle and almost half of the left ventricle. These findings explain why proximal lesions of the RC in RRD hearts can be associated with extensive posterolateral ischemia and mitral dysfunction and should be of practical importance when considering angioplasty or by-pass surgery. The diameters and lengths of the arteries of the RC in RRD hearts were measured and compared with the same parameters in typical right dominant hearts. © 1996 Wiley-Liss, Inc.     

犬左冠状动脉前室间支心肌桥的形态学特征

目的探讨犬壁冠状动脉和心肌桥的形态学特点,为比较解剖学提供资料。方法取犬心41例,10%甲醛溶液固定,解剖显示冠状动脉及其分支,观测心肌桥及壁冠状动脉的出现率。结果犬冠状动脉心肌桥多出现于前室间支、后室间支和左室前支。心肌桥出现率70.7%,前室间支79.3%,心肌桥厚度为0.56±0.61 mm。前室间支前段内径1.64±0.46 mm,厚度0.18±0.06 mm;壁冠状动脉内径1.35±0.46 mm,厚度0.13±0.04 mm。心肌桥近段距第一对角支距离为19.78±8.20 mm,距前室间支起始部距离为24.49±12.37mm,距右冠起始部距离为24.21±5.80 mm。心肌桥纤维走向与壁冠状动脉夹角为68.94±14.38。结论犬冠状动脉心肌桥出现率及位置与人相似,可作为科研动物模型。     

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.     

A very rare anatomic variation of the right ventricular branch: right ventricular descending branch from the anterior interventricular branch

The anterior interventricular branch of the left coronary artery has the most constant distribution in the human heart and rarely gives off right ventricular branches. Here we report a case with a right ventricular branch which diverged from the anterior interventricular branch and descended on the anterior right ventricular wall parallel to the anterior interventricular sulcus; we termed it the right ventricular descending branch. This artery gave a collateral artery to the occluded anterior interventricular branch at the apex, and had prevented anterior myocardial infarction. The right ventricular descending branch should be precisely identified in order to perform successful myocardial revascularization procedures such as coronary artery bypass grafting and percutaneous coronary intervention, especially in a patient with anterior interventricular branch occlusion.     

Histological recognition and classification of the atrioventricular node artery variants: a new approach

BackgroundThere is a controversy in the literature concerning the origin, course, and distribution of the atrioventricular (AV) node artery.MethodsPostmortem coronary angiography, dissection, and microscopic examination were performed in 100 human hearts specimens, providing anatomical, histological, and postmortem angiographic features of the AV node artery.ResultsTwo anatomical types of AV node artery, depending on its length (long–short), were found. “Long-length” (LL) AV node artery supplied with blood almost all the AV conducting tissue in 72 cases. It consisted of a horizontal and descending part ending in two branches. “Short-length” (SL) AV node artery had only a horizontal part, perfusing exclusively the AV node and several times the nonpenetrating main bundle of His. In 67 of 100 cases, the AV arteries were arising from the right coronary artery, distal to the posterior descending (PD) artery. The AV node artery never originated from the PD artery. In 54 of 100 cases, it passed under the coronary sinus (CS) and in the remaining 46 it passed underneath the right atrium endocardium.ConclusionsThe above-described postmortem coronary angiographic findings are essential for interventional cardiologists and cardiac surgeons. Damage to the LL or SL type of AV node artery may cause severe or limited AV conduction abnormalities, respectively. Furthermore, the course of AV node artery under the CS makes it susceptible to injuries provoked by diagnostic or therapeutic procedures involving the CS area.