Carotid Endarterectomy and Carotid Artery Stenting for Patients With Crescendo Transient Ischemic Attacks: A Systematic Review.

Importance: Thromboembolic stroke attributable to an ipsilateral carotid artery plaque is a leading cause of disability in the United States and a major source of morbidity. Randomized clinical trials have demonstrated the efficacy of carotid endarterectomy and carotid stenting at minimizing stroke risk in patients with minor stroke and transient ischemic attack. However, there is no consensus on guidelines for medical management and the timing of revascularization in patients with multiple recurrent episodes of transient ischemic attack over hours or days, an acute neurological event known as crescendo transient ischemic attack. Objective: To review the management of and timing of intervention in patients presenting with crescendo transient ischemic attack. Evidence Review: This systematic review included all English-language articles published from January 1, 1985, to January 1, 2019, available from PubMed (MEDLINE) and Google Scholar. Articles were excluded if they did not include analysis of patients with symptoms, did not report the timing of intervention after crescendo transient ischemic attack, or mixed analysis of patients with stroke in evolution with patients with crescendo transient ischemic attack. The quality of the evidence was assessed with the modified rating from the Oxford Centre for Evidence-based Medicine. Observations: Patients with crescendo transient ischemic attack were found to have a higher risk of stroke or death after carotid endarterectomy compared with patients with a single transient ischemic attack or stable stroke. With medical therapy alone, a considerable number of patients with crescendo transient ischemic attack experience a completed stroke within several months and have a poor prognosis without intervention. Urgent carotid endarterectomy, typically performed within 48 hours of initial presentation, is beneficial in carefully selected patients. There have been several reports of operative treatment within the first 24 hours of presentation; however, review of these reports does not show any additional benefit from emergency treatment. Carotid artery stenting is reserved only for selected patients with prohibitive surgical risk for endarterectomy. The literature does not clearly support any additional benefit of intravenous heparin therapy over mono or dual antiplatelet therapy prior to carotid endarterectomy. Conclusions and Relevance: Crescendo transient ischemic attack is best managed with optimal medical management as well as urgent carotid endarterectomy within 2 days of presentation. Surgical endarterectomy appears to be preferred because of the increased embolic potential of bifurcation plaque, whereas stenting is an option for patients with contraindications for surgery. With ongoing advances in cerebrovascular imaging and medical treatment of stroke, there is a need for better evidence to determine the optimal timing and preoperative medical management of patients with crescendo transient ischemic attack.