Twenty-five studies reporting 3,139 operations for asymptomatic stenosis and 11,917 operations for symptomatic stenosis were included.
There were 33 deaths (1.31%, 95% CI: 0.80, 1.78) attributed to endarterectomy for asymptomatic stenosis and 172 deaths (1.81%, 95% CI: 1.46, 2.13) attributed to surgery for symptomatic stenosis (OR 0.69, 95% CI: 0.49, 0.99). The relative OR of death after surgery for asymptomatic versus symptomatic stenosis showed no statistically-significant heterogeneity between studies.
Two studies gave no information on the causes of death. Among the remainder, the risks of non-stroke death were 0.81% (95% CI: 0.48, 2.25) and 0.81% (95% CI: 0.60, 0.99) after surgery for asymptomatic and symptomatic stenosis, respectively.
The risk of fatal stroke was 0.47% (95% CI: 0.20, 0.79) and 0.91% (95% CI: 0.51, 1.14) for asymptomatic and symptomatic stenosis, respectively, and the OR was 0.57 (95% CI: 0.38, 0.98).
The overall risks of stroke and/or death were 3.35% (95% CI: 2.38, 4.31) for asymptomatic stenosis and 5.18% (95% CI: 4.30, 6.06) for symptomatic stenosis, and the OR was 0.61 (95% CI: 0.51, 0.74). There was no significant heterogeneity between studies in the relative odds of stroke and/or death after surgery for asymptomatic and symptomatic stenosis.