The Internal Thoracic Artery: An Anatomical Narrative Review

Abstract

The internal thoracic artery (ITA) is a paired vessel originating from the first part of the subclavian artery, descending along the inner thoracic wall in close relation to the sternum. Owing to its reliable caliber, predictable course, and favorable long-term patency, the ITA plays a critical role in both clinical anatomy and surgical practice, particularly in coronary artery bypass grafting. This review synthesizes current anatomical knowledge of the ITA, emphasizing its origin, course, branching patterns, and collateral circulation. Variations in its trajectory, branching morphology, and termination are examined in detail, along with rare anomalies such as duplication and complete absence. Surgical relevance is addressed, with a focus on harvesting techniques, the impact of competitive flow, and strategies to manage side branches. Nomenclature is briefly discussed, noting the adoption of “internal thoracic artery” as the primary term. By integrating findings from cadaveric, radiological, and surgical studies, this review highlights the anatomical variability of the ITA and its implications for thoracic, cardiovascular, and reconstructive procedures. Understanding these variations is essential for optimizing surgical outcomes and reducing perioperative complications.