Introduction: Knowledge of normal anatomy and variations in the branching pattern of coronary arteries is of utmost importance to identify the cause of coronary artery diseases and to intervene it. Since the left main coronary artery (LMCA) system is the commonly affected vessel, this study was conducted to learn the branching pattern of left main coronary artery in North Karnataka population.
Materials and Methods: 85 adult heart specimens were collected from routine under graduate and post graduate dissection at Belgaum Institute of Medical Sciences, Belagavi. The left main coronary artery and its branches were dissected and tabulated for number of terminal branches. Photographs were taken wherever necessary and results were compared with previous studies.
Results: Out of 85 specimens studied in 49 (57.66 %) specimens the left main coronary artery bifurcated into left anterior descending (LAD) and left circumflex artery (LCx). In 32 (37.66 %) specimens the left main coronary artery trunk trifurcated and the 3 branches were left anterior descending, left circumflex artery and left diagonal (LD) artery. In 3 (3.5 %) specimens it quadrifurcated with 2 left diagonal arteries between the left anterior descending and left circumflex artery, while in 1 (1.18 %) specimen it pentafurcated with 2 left diagonal arteries and one left marginal artery between the left anterior descending and left circumflex artery.
Conclusion: The left main coronary artery terminates in bifurcation, trifurcation, quadrifurcation and sometimes pent furcation, such high degree of variability of left coronary artery and its branching patterns have diagnostic and therapeutic implications. Adequate knowledge of these variations and its incidence is important for the interpretation of coronary angiography, cardiac catheterization and myocardial revascularization surgeries.
Keywords: Left main coronary artery, Branching pattern, Coronary angiography
