Morphometric Characterization and Anatomical Variations of Coronary Ostia in Human Hearts: Implications for Coronary and Aortic Interventions

Abstract Background Coronary ostial morphology and position show considerable anatomical variation and are clinically relevant during coronary angiography, catheter-based interventions, aortic valve procedures, and aortic root surgery. Objective To evaluate the morphometric characteristics and anatomical position of the right and left coronary ostia and their clinical significance. Methods Sixty embalmed human heart specimens preserved in 10% formalin were examined. The number, shape, dimensions, and position of the coronary ostia were documented relative to the upper margin of the corresponding aortic cusps, sinotubular junction, and aortic valve commissures. Ostial and cusp dimensions were measured using a digital Vernier caliper. Results The mean diameter of the right coronary ostium was 4.78 mm (range, 2.7–8.8 mm), compared with 5.02 mm (range, 3.1–10.6 mm) for the left. Mean ostial height from the aortic root was 13.70 mm on the right and 14.17 mm on the left. Most right coronary ostia (86.7%) were located above the upper cusp margin, whereas 90% of left coronary ostia were at cusp level. Most ostia were below the sinotubular junction (right, 81.7%; left, 85%). Right coronary ostia were predominantly near Commissure I (58.3%), while left ostia were mainly central (56.7%) or near Commissure II (31.7%). Conclusion Coronary ostia demonstrate distinct side-specific variations in diameter, height, and spatial position. These morphometric findings provide useful anatomical reference data for coronary catheterization, aortic root surgery, coronary revascularization, and transcatheter aortic valve procedures.