Analysis of clinical features and influencing factors of rebleeding after bypass surgery in patients with hemorrhagic moyamoya disease

Abstract

Objective To analyze the rebleeding features and possible influencing factors after bypass in patients with hemorrhagic moyamoya disease. Methods From May 2005 to May 2010, 89 patients with hemorrhagic moyamoya disease operated with bypass surgery in the Fifth Affiliated Hospital of Zhengzhou University were followed up. The end point event was rebleeding. The clinical features in patients with rebleeding were analyzed. Cox regression model was used to analyze the possible influencing factors of rebleeding. Results They were followed up for 71.3±10.2 months. In 89 patients, 33(37.1%)had rebleeding. The median age of rebleeding was 48 years old, and the peak age of bleeding was 40-50 years old, accounting for 39.4%(13/33). The median time from having nervous system symptoms to the first bleeding was 13.5(4-21)months. The interval time from the first to the second bleeding was 11.5(7-24)months. There was significant difference(P=0.001). The median modified Rankin scale(mRS)score of the first bleeding was 2(0-5), the second bleeding score was 3(1-5). There was significant difference(P=0.002). Multivariate Cox regression analysis showed that in addition to age(RR, 1.288, 95% CI 0.991-1.672, P=0.058), intracranial collateral vessel formation(RR, 1.271, 95% CI 1.009-3.184), the mRS of the first bleeding was >2(RR, 4.173, 95% CI 1.891-7.544), the time from complete evacuation of intracranial hematoma to bypass >1 month(RR, 2.991, 95% CI 2.670-5.978), anterior choroidal artery dilatation(RR, 3.316, 95% CI 1.135-8.741), posterior communicating artery dilatation(RR, 2.971, 95% CI 1.653-4.465), combined aneurysm(RR, 3.059, 95% CI 1.973-5.065), combined hypertension(RR, 5.587, 95% CI 2.345-10.218)were the independent risk factors for affecting rebleeding(all P<0.05). Conclusions The proportion of rebleeding in patients with hemorrhagic moyamoya disease is higher after bypass. The time of rebleeding is shorter, and the conditions become aggravated. The possible risk factors for rebleeding should be prevented and treated as early as possible. Key words: Cerebral bottom abnormal vascular network disease; Disease attributes; Risk factors; Regression analysis; Rebleeding