Right Aortic Arch and Arterial Flow Steal: Case Report

Abstract

The aortic arch develops around the seventh week of gestation from the migration and regression of the branchial arches. The fourth arch gives rise to the aortic arch after the regression of the right dorsal root. When this regression occurs on the left side, it may result in a right aortic arch. This study reports a 32-year-old female patient with a right aortic arch who presented to the outpatient clinic with complaints of tingling and numbness in the left upper limb. On physical examination, there was a decrease in pulses in this limb during thoracic outlet maneuvers. Computed tomography identified the aortic arch and thoracic aorta on the right side, with tracheal stenosis and a retroesophageal course. CT angiography revealed more than 50% stenosis at the origin of the left subclavian artery. Duplex scan demonstrated flow with a retrograde meso-systolic component in the left vertebral artery, a finding compatible with a subclavian steal phenomenon. This is a rare case of right aortic arch with an aberrant left subclavian artery without Kommerell’s diverticulum. The case highlights the importance of correlating clinical findings with imaging studies in the investigation of vascular symptoms, contributing to accurate diagnosis and appropriate therapeutic decision-making.