CARDIAC DOMINANCE
Annotated Bibliography
Source #1
Citation: Omerbasic, Edin, et al. “Prognostic Value of Anatomical Dominance of Coronary Circulation in Patients with Surgical Myocardial Revascularization.” Medical Archives, vol. 69, no. 1, 2015, p. 6., https://doi.org/10.5455/medarh.2015.69.6-9.
Summary Content:
Who are the researchers?
The primary author, Edin Omberbasic MD, is a cardiothoracic surgeon who specializes in newborn cardiac surgery and early surgical correction of congenital heart defects. He received his MD from the Sarajevo Medical School in Bosnia and Herzegovina in 2004, and currently practices at the Institute of Heart Disease in the Cardiac Surgery Clinic at the University of Sarajevo.
Other authors:
Aida Hasanovic is an associate professor in the Department of Anatomy, faculty of Medicine, at the University of Sarajevo.
Amir Omberbasic MD specializes in cardiology and internal sports medicine at the Policlinic in Sarajevo, Bosnia and Herzegovina.
Sanko Pandur MD works as a cardiac surgeon for the Institute of Heart Disease in the Cardiac Surgery Clinic at the University of Sarajevo.
What was the purpose of the study?
The purpose of the study was to record cardiac dominance in patients undergoing cardiac revascularization and assess the extent to which cardiac dominance affects prognosis following this procedure. Researchers wanted to determine which dominance pattern, if any, was detrimental to prognosis following this operation. Most patients are right-dominant, so any findings connected to right dominance could be very significant. Little to no study of this correlation had been published prior to this paper.
Participants/Subjects:
The research included 100 human participants from a pool of patients undergoing cardiac revascularization (coronary artery bypass grafting surgery) at the Clinic for Cardiac Surgery at the University of Sarajevo. Age of patients varied from 40 to 70 years old, and no preference or significance was placed on age or gender.
What methods were used in the study?
For this study the researchers opened and observed the medical records of the patients who gave consent. Researchers then estimated demographic data and assessed patients’ conditions prior to and after the surgical procedure, along with each patient’s cardiac dominance pattern. The main statistical tests performed were the x2 (chi-square) and Mann-Whitney tests, which are responsible for comparison between experimental data and a model, and null hypothesis evaluation, respectively. These tests statistically demonstrate whether there is a connection between cardiac dominance and prognosis following revascularization.
What did researchers find?
Observation of medical records and statistical analysis suggested a link between inability of revascularization, lethal outcome, and hospital stay with left dominance. The conclusion was that left cardiac dominance is a significant risk factor for patients needing myocardial revascularization. Furthermore, left cardiac dominance corresponds to a lower qualification for revascularization entirely. An additional risk on top of left cardiac dominance was the female gender. These findings are of great significance as individuals with left cardiac dominance may have poorer quality of life following myocardial revascularization, the typical treatment for blocked/impaired blood flow to the heart. Determining cardiac dominance requires a semi-elaborate procedure not performed on healthy individuals, meaning most people do not and will not know their cardiac dominance pattern. However, this study shows that cardiac dominance greatly affects how a patient should be treated for coronary artery issues, and screening procedures should be performed prior to surgical treatment.
Source #2
Citation: Parikh, Nisha I., et al. “Left and Codominant Coronary Artery Circulations Are Associated with Higher in-Hospital Mortality among Patients Undergoing Percutaneous Coronary Intervention for Acute Coronary Syndromes.” Circulation: Cardiovascular Quality and Outcomes, vol. 5, no. 6, 2012, pp. 775–782., https://doi.org/10.1161/circoutcomes.111.964593.
Summary Content:
Who are the researchers?
Nisha I. Parikh, listed as the primary author of this study, is an MD MPH in Cardiology at the University of California San Francisco. She focuses on cardiovascular disease prevention and cardiovascular disease in women and during/after pregnancy. She also has significant experience in epidemiology and population science. Currently she works in the Cardiology Division of Queens Medical Center in Honolulu, Hawaii.
Other authors:
Emily F Honeycutt, MS; Matthew T. Roe, MD, MHS; Megan Neely, PhD; J. Rosenthal, BA; Murray A. Mittleman, MD, DrPh; Joseph P. Carrozza Jr, MD, and Kalon K.L. Ho, MD, MS all work with Nisha Parikh at the Queens Medical Center in Honolulu, HI, in the Cardiology Division.
What was the purpose of the study?
The goal of this study was to correlated left and co-dominant cardiac patterns with risks and in-hospital mortality associated with acute coronary syndromes. Acute coronary syndromes are any conditions that affect the flow of blood through the heart or cause a blockage. Previous studies similar to this one have been conducted, but none with the same scope and massive sample size.
Participants/Subjects:
The researchers of this study used over 200,000 instances of percutaneous coronary interventions (treatment for acute coronary syndromes) from 2009 to 2010 using the National Cardiovascular Data Registry Cath Percutaneous Coronary Intervention Database (CathPCI). Race and gender are more closely examined than in the previous study, with interesting results.
What methods were used in the study?
They used equations and linear regression analyses, as well as sub-group analyses based on cardiac dominance and case result to correlate multiple variables. Predominantly, in-hospital mortality and cardiac dominance were examined and related. Excluded were patients who had multiple interventions. Statistical analyses examined both left versus right dominant and co versus right dominant, and consisted of an exchangeable working correlation matrix, as well as multivariable models. Specifically, the C-statistic and HL test were further looked at to determine discrimination and further correlate cardiac dominance and in-hospital mortality. Overall, a litany of analysis was performed to accurately evaluate the relationship between cardiac dominance and in-hospital mortality, based on factors like race and sex.
What did researchers find?
Overall, it was concluded that, in line with my previous source, left and co-dominance are more closely associated with in-hospital mortality following percutaneous coronary intervention. They also found variable incidence rates of each type of cardiac dominance based on race and gender. Similar to expected values, researchers found 82% of patients with right cardiac dominance, 8% with co-dominance, and 10% exhibiting left cardiac dominance. White patients and women showed right dominance more commonly than left or co-dominance, while black, Hispanic/Latino, and men demonstrated co-dominance more commonly than the average. Further research in this area is needed to better understand this relation, as well as more strongly identify risk factors such as identity. Future experiments/studies pertaining to cardiac dominance and in-hospital mortality should include a wide diversity of patients to ensure high external validity.
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Source #3
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Citation: Wang, Li, et al. “Association between Coronary Dominance and Acute Inferior Myocardial Infarction: A Matched, Case-Control Study.” BMC Cardiovascular Disorders, vol. 19, no. 1, 2019, https://doi.org/10.1186/s12872-019-1007-5.
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Summary Content:
Who are the researchers?
The primary authors listed are Li Wang and Jiamei Li, both associated with Department of Critical Care Medicine at the Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an China.
Other authors:
Ya Gao, Ruohan Li, Jingjing Zhang, and Ziaochuang Wang all also work in the Department of Critical Care Medicine at the Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an China.
Dan Su works in the Department of Cardiology at the Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an China,
Tao Wang is located at the Department of Cardiology at the Xi’an Children’s Hospital, Xi’an, China.
Guang Yang works in the Department of Cardiology at Shaanxi Provincial People’s Hospital, Xi’an, China.
What was the purpose of the study?
This study continues research based on conclusions such as that of the previous study. Following a suggested association between left cardiac dominance and higher mortality following acute coronary syndrome, the question is whether cardiac dominance affects one’s risk of heart attacks. Previous study has occurred on this subject and demonstrated similar results to this more recent publication. Most of this research was previously limited to the United States and other Western nations.
Participants/Subjects:
The case study utilized 265 willing human participants who suffered from acute myocardial infarction between 2011 and 2014, along with 530 age/sex matched participants serving as controls. All patients were above the age of 18 and currently taken from the Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an China.
What methods were used in the study?
The study consisted of a large review of numerous patient records and observation over a longer period. Various statistical analyses were then performed to determine relation of cardiac dominance and incidence of myocardial infarction (heart attacks). More specifically, the t-test and x2 (chi-square) test were performed on the given data. Similar to the first study mentioned, which also included these analyses, the t-test and chi-square test serve to determine the extent of error in correlation and compare data to expected values. By applying these tests to the data, researcher greatly enhanced both the validity and applicability of results.
What did researchers find?
Somewhat in contrast to previous studies, though not illogical based on the functionality of cardiac dominance, right dominance is the most at risk cardiac dominance pattern for heart attack. The study concludes a significant link/risk associated with right cardiac dominance. Right cardiac dominance is the most common pattern, as about 70% of the population possess this anatomical development. Heart attacks are also extremely common in most demographics, making these findings very important to future understanding and treatment of heart attacks. While most people will not discover their cardiac dominance unless heart disease or similar pathology is already a concern, this data adds yet another risk factor for heart attacks to the already lengthy list. Furthermore, those patients with right cardiac dominance who suffer from a heart attack tend to have worse damage than left and co-dominant patients. This nuance in prognosis will affect treatment following myocardial infarction based on the patient’s cardiac dominance.
The field needs more experimentation in this area to fully quantify the elevated risk of individuals with left cardiac dominance, as this study’s limited sample size prevents a clear number to show this. More work is also required to cover all intricacies of the correlation between heart dominance and heart attacks, due to the multitude of other factors that increase risk, and the difficulty a single study faces in minimizing these factors.