Abstract
BACKGROUND: Severe atherosclerotic internal carotid artery stenosis may progress to complete internal carotid artery occlusion (ICAO). Therefore, ICAO represents an advanced form of carotid artery disease. We sought to investigate the association between ICAO with atherosclerotic disease in other arterial beds and vascular risk factors and to identify the patient implications of the diagnosis of ICAO.
MATERIALS AND METHODS: Using the term "Internal carotid artery occlusion", a search of PubMed/MEDLINE, Scopus and Embase between 1980 and 2025 revealed 10,588 results. After exclusion of case reports, letters to the Editor and Editorials, 5,771 reports were identified. Following meticulous screening of the identified reports, 28 studies specifically addressing ICAO patient cohorts were included in the final analysis. A quantitative and qualitative synthesis analysis was performed. A questionnaire was subsequently developed and sent out to 63 participants from the United States (n=21) and several European countries (n=42), aiming to achieve consensus regarding the optimal management of patients with ICAO. Three participants did not respond. The Consensus Coordinator abstained from voting to avoid introducing bias, resulting in a final voting panel of 60 participants.
RESULTS: Across included studies, the proportion of patients with ICAO presenting with neurologic symptoms varied widely, ranging from 38-100%, while approximately 24-27% of patients were asymptomatic at the time of diagnosis. Consensus (≥75%) was achieved in 11 of the 17 (64.7%) pre-specified statements. Most participants agreed that atherosclerotic ICAO represents a systemic manifestation of advanced atherosclerosis rather than isolated cerebrovascular pathology (56/60; 93.3%). Duplex ultrasound should be used as the first-line diagnostic tool for suspected ICAO, with CTA or MRA confirmation if necessary (59/60; 98.3%). Optimal medical therapy (including antiplatelet, antihypertensives, statins, and glycemic control) remains the cornerstone of ICAO management (59/60; 98.3%). Lifestyle and metabolic risk factor optimization, smoking cessation, optimizing body weight, a healthy diet and exercise, should be strongly advised in all ICAO patients (60/60; 100%). Most participants concurred that ICAO revascularization should be centralized in specialized vascular-neuro centers equipped for intra-operative neuromonitoring and advanced hemodynamic control (57/60; 95.0%). Finally, most participants agreed that current evidence for ICAO intervention is insufficient and that a global registry should be created to record outcomes and guide future trials (56/60; 93.3%).
CONCLUSIONS: This international, multi-specialty consensus highlights ICAO as a marker of advanced, systemic atherosclerosis. Management should emphasize comprehensive evaluation for multisystem vascular disease and aggressive modification of cardiovascular risk factors. Best medical therapy remains the cornerstone of the management of patients with ICAO, with conservative or invasive interventions considered selectively based on symptom status, anatomic considerations, procedural risk, and institutional expertise, to reduce the overall cardiovascular disease burden.