Coronary Artery Dominance and Myocardial Infarction: A Review of Anatomical Variations, Physiological Impacts, and Clinical Implications in Inferior Myocardial Infarction.

Abstract

Background: Coronary artery dominance defined by the vessel supplying the posterior descending artery (PDA) plays a critical role in the prognosis and management of myocardial infarction. While right dominance is the most common anatomical pattern, left dominance is associated with a higher risk of adverse outcomes, particularly in inferior wall myocardial infarctions (MI).

Methodology: This narrative literature review was conducted using scientific databases including PubMed, NCBI, Google Scholar, as well as publisher platforms such as ScienceDirect and SpringerLink. Peer-reviewed English-language articles published from 1940 to 2025 were reviewed. Foundational anatomical concepts were supplemented by standard anatomical textbooks. Clinical relevance was ensured by synthesizing literature based on pre-formulated research questions.

Results: Right coronary dominance is present in approximately 75% of individuals, while left and co-dominant patterns account for the remainder. Right and co-dominance are generally associated with better anatomical and clinical outcomes due to more robust collateral circulation. In contrast, left dominance is linked to an increased risk of ischemia in inferior wall MIs due to insufficient perfusion to the PDA territory. Although coronary flow reserve may be influenced by dominance type, this remains an underexplored area. Clinical outcomes can be improved by aligning ECG findings with coronary anatomy and tailoring surgical or interventional strategies accordingly. Routine documentation and confirmation of coronary dominance either incidentally or deliberately via imaging can aid clinical decision-making.

Conclusion: Coronary artery dominance is a critical anatomical and physiological factor that significantly influences outcomes in inferior STEMI. Integrating coronary dominance assessment into diagnostic and treatment protocols using ECG, angiography, and emerging tools such as AI can help personalize patient management, reduce complications, and improve prognosis. Future research should focus on quantifying the physiological effects of dominance types and optimizing therapeutic strategies accordingly.