Abstract 84: Low Risk of Stroke or Death Among Patients With Recently Symptomatic Carotid Stenosis Awaiting Revascularisation - A Pooled Analysis of Randomised Trials

Abstract

Background: Historical data suggest that patients with recently symptomatic carotid stenosis are at high risk of early recurrent stroke. Guidelines therefore recommend revascularization within 2 weeks of symptoms. We assessed the risk of stroke or death occurring before revascularization in modern trials of symptomatic carotid stenosis. Methods: We pooled data of all individual patients with symptomatic carotid stenosis randomised to stenting (CAS) or endarterectomy (CEA) in the EVA-3S, SPACE, ICSS and CREST trials. The outcome event (OE) was death or any stroke occurring between randomization and treatment by CAS or CEA, or up to 120 days after randomization among patients not undergoing treatment in this period. Results: 4707 patients were included in the analysis. Median time from qualifying event until randomization was 18 (interquartile range 7-50) days. Median time from randomization until treatment was 6 (2-11) days in the CAS group, and 7 (3-12) days in the CEA group (p<0.001). 31% of patients in the CAS group and 27% in the CEA group underwent revascularization within 14 days of the qualifying event. The OE occurred in 21 patients (CAS: 8, CEA: 13), all within 31 days of randomization (Kaplan Meier estimate: 2.4%, standard error 0.7%; fig.), including 18 non-fatal strokes, 1 fatal stroke, and 2 non-stroke related deaths. In 2 of the patients, the date of the qualifying event was unknown, in 8 patients the OE occurred within 14 days of the qualifying event and in 11 patients >14 days after the qualifying event. All patients with the OE had severe (70-99% degree) stenosis. No other baseline variables predicted the OE. Discussion: Despite the fact that less than a third of patients underwent revascularization within 14 days of the qualifying event, only 2.4% of patients had a recurrent stroke or died before treatment. The risk is lower than expected from historical data, which may reflect advances in medical therapy. Patients at risk are those with severe degree of stenosis.