Anatomy and possible variants of left subclavian artery and vertebral arteries

The left subclavian artery (LSA) and vertebral arteries (VAs) undergo complex embryological development, resulting in a wide spectrum of anatomical variants. These variations are of significant clinical relevance due to their potential impact on cerebral, spinal, and upper limb perfusion, as well as their influence on surgical and endovascular decision-making.

A comprehensive review of the available literature was performed focusing on the embryology, anatomical variants, and clinical implications of LSA and VA anomalies. Relevant anatomical, radiological, surgical, and endovascular studies were analyzed to identify common variants, their prevalence, and associated procedural risks.

The LSA typically arises as the third branch of the aortic arch, while the VAs develop from longitudinal anastomoses of the cervical intersegmental arteries. Variants such as aberrant LSA, bovine arch configuration, isolated LSA, and anomalous origins of the VAs are well documented. These anomalies may significantly complicate open aortic arch surgery, thoracic endovascular aortic repair (TEVAR), coronary artery bypass grafting, and cervical or cranial interventions. Failure to recognize these variants preoperatively may lead to inadequate cerebral or spinal cord perfusion and increase the risk of iatrogenic injury.

Anatomical variants of the LSA and VAs are common and clinically important. Accurate preoperative identification using advanced imaging is essential to optimize surgical and endovascular planning, reduce procedural complications, and ensure adequate organ perfusion. Tailored strategies should be adopted when managing patients with these vascular anomalies to improve outcomes and procedural safety.