Lessons learnt from carotid artery trials

The objective of the authors is to assess the natural history of carotid artery disease and the role of carotid intervention in preventing ipsilateral stroke. The development of endovascular techniques for correction of carotid artery stenoses made this less invasive technique very popular, with an inherent risk of unregulated overuse by a variety of medical specialists, who are not always well informed on the natural history of carotid artery disease. It re-opened the discussion on the value of carotid endarterectomy for stroke prophylaxis. This ongoing debate offers the opportunity to distil evidence-based guidelines for the management of extracranial carotid artery stenoses. In recent papers, some authors expressed doubts on the validity and general applicability of the results of the pivotal randomised trials of carotid endarterectomy. The excellent results in terms of operative outcome and long term stroke prevention would, according to certain comments, not be attainable in routine practice. Another criticism of carotid endarterectomy is its higher operative morbidity in terms of cranial nerve lesions and myocardial infarctions, compared to endovascular procedures. This consideration is, for some authors, the main reason to espouse carotid artery stenting as a better alternative to carotid endarterectomy. Any evidence supporting this point of view is missing. The supposed equivalence or non-inferiority of carotid artery stenting is purely speculative. The aim of this review paper is to summarize the crude data of carotid surgery trials. The authors aim to answer four questions. For which lesions is carotid endarterectomy most beneficial ? Are the results of randomised carotid surgery trials biased by the selection of patients ? Is operative morbidity, other than stroke, under-estimated ? Is carotid artery stenting safe and efficacious ? An in-depth review with a critical analysis is made of recently published and on-going trials, comparing carotid surgery with percutaneous carotid angioplasty.