No long-term excess mortality in 280 patients with ruptured distal anterior cerebral artery aneurysms

OBJECTIVE: The aim of this study was to assess the long-term excess mortality after the rupture of distal anterior cerebral artery (DACA) aneurysms compared with that of a matched general Finnish population in an unselected, population-based series. METHODS: We identified 280 consecutive patients (119 men, 161 women) treated for ruptured DACA aneurysms (clipped, 262; coiled, 10; no intervention, 8) at two neurosurgical centers serving solely the southern and eastern parts of Finland from 1976 to 2003. All patients were followed from subarachnoid hemorrhage until death or the end of 2004. No patients were lost to follow-up. Long-term excess mortality was estimated using the annual relative survival ratio compared with the general Finnish population matched by age, sex, and calendar time. RESULTS: The median follow-up period was 9.6 years (range, 0.1-29 yr). The 3-year cumulative relative survival ratio was 0.84 (95% confidence interval, 0.78-0.88), implying 16% excess mortality in the patient group during the first 3 years after subarachnoid hemorrhage. The annual relative survival ratio attained 1.0 at the fourth year of follow-up, indicating no excess mortality thereafter. There were four episodes of recurrent subarachnoid hemorrhage and only one from a treated DACA aneurysm, with a 10-year cumulative risk of 1.4% (95% confidence interval, 0.0-3.0). Cardiovascular disease and cancer were the leading causes of death after 10 years of follow-up. CONCLUSION: After surviving 3 years after the rupture of a DACA aneurysm, the patients' long-term survival became similar to that of the matched general population. Rebleeding of treated DACA aneurysm was rare.