Abstract Body: ABSTRACT
Background
In the Carotid or Middle cerebral artery Occlusion Surgery Study (CMOSS), we found no significant difference between the bypass surgery group and the medical group with respect to the primary composite outcome of stroke or death within 30 days or any subsequent ipsilateral ischemic stroke within 2 years of follow-up. We now extend the long-term follow-ups to 10 years.
Methods
We randomly assigned symptomatic patients with hemodynamically compromised internal carotid artery (ICA) or middle cerebral artery (MCA) occlusion to extracranial-intracranial (EC-IC) bypass surgery plus medical treatment or medical treatment alone at 13 centers in China. We extended the follow-ups from the original 2 years to 10 years to assess long-term outcomes. The primary outcome was a composite of stroke or death within 30 days or ipsilateral ischemic stroke beyond 30 days after randomization.
Results
324 patients were assigned to the surgery (n=161) or medical group (n=163); the median duration of follow-up was 7.6 years (interquartile range [IQR], 2.3 to 9.2). The primary outcome occurred in 18 of 161 patients (11.2%) in the surgical group, significantly lower than that in the medical group (32 out of 163 patients [19.6%]; relative risk [RR], 0.57; 95% confidence interval [CI], 0.33 to 0.97; P=0.04). The risk of any stroke was 16.1% in the surgical group vs 23.3% in the medical group (RR, 0.76; 95% CI, 0.52 to1.13; P=0.15); the all-cause mortality was 8.1% in the surgical group vs. 8.6% in the medical group (RR, 0.94; 95% CI, 0.46 to 1.94]; P=0.93).
Conclusions
Among symptomatic ICA or MCA occlusion patients with hemodynamic insufficiency, the addition of extracranial-intracranial bypass surgery to medical treatment was safe and led to a lower risk of recurrent stroke through 7 years of follow-up than medical treatment alone. (ClinicalTrials.gov number, NCT01758614.)