Duration of asymptomatic status and outcomes following carotid endarterectomy and carotid artery stenting in the Carotid Revascularization Endarterectomy vs Stenting Trial

Background: Most carotid revascularization studies define asymptomatic as symptom-free for more than 180 days; however, it is unknown if intervention carries similar risk among those currently asymptomatic but with previous symptoms (PS) vs those who were always asymptomatic (AA). Methods: We compared the periprocedural and 4-year risks of PS vs AA patients in the Carotid Revascularization Endarterectomy vs Stenting Trial (CREST) randomized to carotid endarterectomy (CEA) or carotid artery stenting (CAS)/angioplasty. Proportional hazards models adjusting for age, sex, and treatment were used to assess the risk of periprocedural stroke and/or death (S+D; any S+D during periprocedural period), stroke and death at 4 years (any S+D within the periprocedural period and ipsilateral stroke out to 4 years) and the primary end point at 4 years (any stroke, death, and myocardial infarction within the periprocedural period and ipsilateral stroke out to 4 years). Analysis was performed pooling the CEA-treated and CAS-treated patients, and separately for each treatment. Results: Of 1181 asymptomatic patients randomized in CREST, 1104 (93%) were AA and 77 (7%) were PS. There was no difference in risk when comparing the AA and PS cohorts in the pooled CAS+CEA population for periprocedural S+D (2.0% vs 1.3%), S+D at 4 years (3.6% vs 3.2%), or the primary end point (5.2% vs 5.8%). There were also no differences among those assigned to CEA (periprocedural S+D, 1.5% vs 0%; S+D at 4 years, 2.7% vs 0%; or primary end point, 5.1% vs 2.4%) or CAS (periprocedural S+D, 2.5% vs 2.8%; S+D at 4 years, 4.4% vs 6.9%; or primary end point, 5.3% vs 9.8%) when analyzed separately. Conclusions: In CREST, only a small minority of asymptomatic patients had previous ipsilateral symptoms. The outcomes of periprocedural S+D, periprocedural S+D, and ipsilateral stroke up to 4 years, and the primary end point did not differ for AA patients compared with PS patients.