Clinically Significant Morphology of the Internal Thoracic Artery Branches

Purpose The internal thoracic artery (ITA) is the preferred conduit for coronary artery bypass grafting (CABG) due to its superior long-term patency. However, variations in ITA morphology, particularly the presence of proximolateral branches (PLBs), may influence surgical outcomes and contribute to complications such as graft failure and steal syndrome. This study aimed to quantify the prevalence of ITA branching variations, describe their morphometric characteristics, and assess their potential clinical implications. Methods Sixty-four embalmed cadavers were systematically dissected to expose the ITA and its PLBs. Measurements of vessel diameter, branch length, and branching angle were recorded at predefined anatomical landmarks. Two independent observers conducted all measurements, with inter-observer reliability assessed using intraclass correlation coefficients. Results Significant PLBs were present in 12 cadavers, with three displaying bilateral branches. PLBs originated 0.5–3.8 mm superior to the first rib, with an average branching angle of 87.1°. Males exhibited longer PLBs and greater ITA-sternum distances, whereas females had a larger ITA diameter. Right-sided branches emerged more perpendicularly compared to left-sided branches. These anatomical variations align with findings from clinical imaging studies, highlighting their relevance to surgical procedures involving the ITA. Discussion ITA variations may impact the success of CABG, thoracic nerve blocks, and reconstructive procedures. Preoperative imaging could enhance surgical planning by identifying ITA variants that may influence procedural techniques and outcomes. These findings provide anatomical benchmarks that may contribute to reducing perioperative complications and improving patient-specific surgical approaches. Further research is needed to explore associations between ITA variations and cardiovascular risk factors.