Systematic review of clinical literature for absent common carotid artery.

Objective: Absent common carotid artery (ACCA) is a rare condition, with less than 125 cases reported in the literature. Trends in symptoms, treatments, and outcomes related to ACCA are largely unknown. Methods: We present a case of ACCA in a 77-year-old man who also had asymptomatic severe atherosclerotic stenosis of the ipsilateral internal carotid artery (ICA). Carotid revascularization was performed via transposition of the ipsilateral internal to external carotid artery. The case was successful, and he recovered without complication. We also performed a systematic review of EMBASE and PubMed databases for clinical presentations and treatment outcomes of ACCA. Literature quality was assessed according to the Joanna Briggs Institute case report checklist. Results: We identified 64 cases of ACCA from 61 reports. Over 50% of patients with ACCA presented with cerebrovascular-related symptoms, including 21 (33%) presenting acutely with transient ischemia attack or cerebrovascular accident. Incidence of intracranial aneurysm was disproportionately high, occurring in 10 cases (16%). Hypoplasia or absence of the ipsilateral ICA was seen in 22 cases (35%). Treatment for carotid stenosis or intracranial aneurysm was reported in 12 cases (20%), with no reports of complication or mortality. Only four reports (7%) documented patient race or ethnicity, and 19 (31%) did not describe clinical management. Conclusions: We recommend diagnostic head imaging to detect intracranial aneurysm in adult patients found to have ACCA and hypoplasia or tortuosity of the ipsilateral ICA. We also recommend carotid revascularization in patients found to have severe stenosis of the ipsilateral ICA, and this can safely be performed with open or endovascular methods. Current ACCA case report literature is of low quality and would benefit from improved reporting of patient demographics and clinical management strategies.