Angioarchitecture of the coronary arteries in Mazama gouazoubira (G. Fischer, 1814)

Mazama gouazoubira is a widely distributed deer in the South American continent. However, studies on its anatomical characteristics are still scarce. The objective of this study was to elucidate the coronary circulation of M. gouazoubira. With this aim, after collecting cadavers on highways, twenty-four hearts injected with latex and preserved in formaldehyde at 10% were dissected. The dissections revealed that all specimens presented left coronary dominance, characterized by the origin of the subsinuous interventricular branch from the circumflex branch of the left coronary artery. The number of ventricular branches originated from branches of the left coronary artery was approximately five times higher than that of the right coronary artery. The occurrence of myocardial bridges was registered in 91.7% of the individuals, with bridges predominating over the paraconal interventricular branch. The mean length of the paraconal interventricular sulcus was significantly higher in males (p = 0.02). The number of atrial branches and ventricular branches, length of myocardial bridges and length of subsinuous interventricular sulcus did not vary significantly between sex. Left coronary dominance and high frequency of myocardial bridges in M. gouazoubira are preponderant anatomical traits also present in different species of Ruminantia suborder. Coronary dominance studies in other South American deer species may confirm the correlation of this trait with the evolutionary history of these animals.

Abstract 15360: Coronary Artery Dominance, Anatomical Variants and Anomalies in African American Population

Introduction: Coronary arterial dominance is defined by the vessel which gives rise to the posterior descending artery (PDA). The prevalence of right dominance is 80- 85%, left dominance is 8% and codominance is 7% among the general population. The coronary dominance in African Americans is not well known. The aim of this study was to investigate the coronary dominance in African Americans. Previous studies showed that left dominance and codominance are associated with increased post-percutaneous coronary intervention (PCI) in-hospital mortality in patients with acute coronary syndrome (ACS). Methods: A retrospective analysis of coronary angiograms performed in our facility was done. A total of 556 cases were reviewed from 2018 to 2019. All the data was collected from the electronic medical records. Patients were categorized by race, gender, age, and comorbidities. Angiograms were reviewed and coronary dominance was determined by the vessel which supplied the PDA. Results: From the 556 charts reviewed, 430(77%) cases were performed in African Americans. Of the 430 patients, 220(51%) were male and 210(49%) were female. Mean age was 62.6 years. 370(86%) patients had hypertension, 171(39.7%) had diabetes, 28(6.5%) had peripheral vascular disease, 149(34.6%) had heart failure, 33(7.6%) had history of stroke. 28(6.5%) were on dialysis, 201(46.7%) had dyslipidemia, 14(3.2%) had HIV, 43 (10%) had atrial arrhythmias, 237(55.1%) had history of tobacco use and 21(4.8%) had history of cocaine use. In 390(90.7%) patients, left main coronary artery bifurcated into left anterior descending coronary artery (LAD) and left circumflex artery (LCX). In 40(9.3%) patients, left main coronary artery trifurcated into LAD, LCX and ramus intermedius artery. Among these patients, 303(70.4%) had right coronary dominance, 38(8.8%) had left coronary dominance and 89(20.7%) had codominance. 7 patients had ectasia of the coronary vessels and 8 patients had anomalous origin of coronary vessels. Conclusions: Our study showed that African Americans have higher prevalence of codominance compared to general population. It is important to identify it at the time of coronary angiogram since it has been associated with increased post PCI in-hospital mortality in patients with ACS.

Coronary dominance pattern in Myocardial bridged hearts

Posterior interventricular artery (PIA) present in the posterior interventricular groove over the inferior surface of the heart. Human hearts consist of either Right coronary predominance or Left coronary predominance. Left coronary predominant people are more prone to get ischemic heart diseases. In left coronary predominance entire left ventricle except a part of the right ventricle adjoining anterior interventricular groove supplied by the left main coronary artery. Left coronary dominance has a poor prognosis in acute coronary syndrome when compared with the right coronary predominance. Myocardial bridging may be benign or malignant. So myocardial bridging with left coronary dominance may be a risk factor to the ischemic heart disease. The aim of the present study is to find out the coronary dominance pattern in myocardial bridged hearts in cadavers. Ninety cadaveric hearts were procured from the Department of Anatomy, IMS & SUM Hospital Bhubaneswar. After a simple dissecting procedure, myocardial bridges and coronary dominance patterns were observed. Myocardial bridging was present over the left anterior interventricular artery in 51(56.7%) hearts. Out of 51 myocardial bridged hearts, right coronary predominance is present in 45 (88.24%) hearts and left coronary predominance present in 6(11.76%) hearts. Along with the left dominance, if myocardial bridge present over the left epicardial coronary artery, there may be an increased frequency of myocardial ischemia.

Patterns of Coronary Dominance in Patients undergoing Coronary Angiography

Introduction: Right and left coronary arteries supply the heart. The dominant vessel supplies posterior descending artery and at least one posterolateral branch to inferior surface of heart. The coronary circulation can be: right dominant, left dominant and co-dominant. Objectives: The aim of this study was to determine the different patterns of coronary artery dominance in patients with coronary artery disease. Methodology: A descriptive cross-sectional study was conducted in patients undergoing coronary angiography in cathlab of Nobel Medical College and Teaching Hospital, Biratnagar, Nepal. The coronary angiography was taken from all standard views. For assessing the left dominance, left anterior oblique cranial view was specially focused. Results: There were 72.9% right dominant, 22.2% left dominant and 4.9% co-dominant cases. Both sexes had similar patterns of coronary dominance (73.8% RD, 22.2% LD and 4.0% CD among males whereas, 71.4% RD, 22.1% LD and 6.5% CD among females) as that in total study population. The highest number of patients was found in 60 to 69 years of age group. More number of patients had left dominance in less than 50 years age group than in 50 years and above group. There were no significant differences in pattern of coronary dominance with age groups. Conclusion: The most prevalent type of coronary artery dominance is right dominance followed by left dominance and co-dominance.