Anatomical Variations of Branching Pattern of the Arch of Aorta: A Cadaveric Cross-sectional Study

Introduction: The arch of the aorta normally gives off three major branches from its convex surface. Variations in the branching pattern of the Aortic Arch (AA) are not uncommon. Knowledge of these variations is crucial during aortic instrumentation and thoracic or neck surgeries. Aim: This study aimed to investigate the anatomical variations in the branching pattern of the AA in perinatal and adult cadavers. Materials and Methods: A cross-sectional cadaveric study was conducted in the Department of Anatomy, at Assam Medical College and Hospital, Dibrugarh, from August 2018 to July 2021. The study included cadavers of various ages and both genders (N=46). Perinatal cadavers received from the Obstetrics and Gynecology department were also included. The thoracic cavity was opened by cutting through the costochondral junctions and reflecting the sternum. Fibrofatty tissue was removed to expose the branches of the AA, which were then examined and classified. Variations were observed, and the results were expressed in terms of frequency and percentages. Results: A classical branching pattern (Type-A) was observed in 89.1% of cadavers. Five cadavers (10.9%), comprising four males and one female, exhibited branching patterns different from the classical pattern. Among them, Type-C variation was noted in 4 (8.7%) cadavers, and Type-D variation was found in 1 (2.2%) male cadaver. Conclusion: Having a good understanding of the variations in the branching pattern of the arch of the aorta can be beneficial for surgeons performing complex vascular surgery.