BACKGROUND: Several studies have reported variable rates of perioperative risk of stroke in individuals with tandem stenoses after carotid endarterectomy. Endovascular treatment of extracranial lesions associated with tandem lesions is limited to case reports and small case series.

METHODS: We retrospectively reviewed clinical records and angiographic findings of 132 symptomatic patients with extracranial atherosclerotic disease who underwent elective stent placement at three tertiary care centers. Tandem stenosis was defined as any lesion with intracranial stenosis ≥50% in the same (but not contiguous) vascular distribution distal to primary extracranial stenosis. The study end point was a composite of any stroke or death within 24 hours, at 1- and 6-month postprocedure. The rates of primary end points were compared between patients with or without secondary tandem stenosis.

RESULTS: Out of 132 patients (134 procedures), 27 patients were identified with a tandem stenosis. The stroke and/or death rates at 24 hours were (11.1% vs 7.5%, P = . 69) for patients with tandem stenosis and single stenosis, respectively. The cumulative stroke and/or death rate at 1-month postprocedure (15.0% vs 7.5%, P = .10) and at 6-month postprocedure (26.6% vs 12.8%, P = .08) appeared to be higher among those with tandem stenoses without reaching statistical significance.

CONCLUSIONS: The high risk of postprocedural stroke and/or death observed in this series requires careful assessment of the risk/benefit ratio of endovascular procedures in patients with tandem stenosis.