Abstract TMP83: Optimal Timing For Resumption Of Anticoagulation After Intracranial Hemorrhage In Patients With Mechanical Heartvalves

Abstract

Introduction: Anticoagulation in patients with acute intracranial hemorrhage (ICH) and mechanical heart valves (MHV) is often held to mitigate the risk of ICH expansion or recurrence; however there exists a competing risk of acute ischemic stroke (AIS). Optimal timing to resume anticoagulation after ICH remains uncertain. Methods: We retrospectively studied ICH patients with MHV at two academic hospitals from April, 2000-August, 2018. The primary outcome was a composite endpoint of symptomatic hematoma expansion or new ICH, AIS, and intracardiac thrombus up to 30 days post-ICH. The exposure was timing of re-initiation of anticoagulation classified as early if therapeutic anticoagulation was resumed up to 7 days after ICH; late if ≥7 and up to 30 days after ICH; and never if not resumed or resumed after 30-days post-ICH. Cox proportional hazard models were built adjusted for age, sex, and covariates significantly different in univariate analysis at a pre-specified p-value threshold of 0.05. Results: We identified 184 patients with ICH and MHV (65 anticoagulated early, 100 resumed late, 19 not resumed by day 30 post-ICH). We observed 12 AIS, 16 new ICH, and 6 intracardiac thromboses. The mean time from ICH to anticoagulation in the cohort was 12.7 days. Patients resumed early versus late were more likely to have atrial fibrillation (62% versus 42%), and less likely to be reversed (75% versus 94%), to undergo hematoma evacuation (23% versus 43%), have midline shift (27% versus 52.9%), and to have intracerebral involvement (26% versus 49%). There was no significant difference in the hazard of AIS, new or symptomatic ICH expansion, or the composite outcome among those resumed early versus late. Patients not resumed within 30 days post-ICH had a significantly higher risk of AIS compared to those resumed within 30 days (HR 15.9; 95% C.I.1.9-129.7, p=0.0098). Discussion: In this study of ICH patients with MHV, there was no difference in the 30-day thrombotic and hemorrhagic brain-related outcomes in patients anticoagulated within 7 days versus 7-30 days. Withholding anticoagulation within the first 30 days was associated with a significantly higher risk of AIS. Our findings provide a discrete time window to guide resumption of anticoagulation in MHV patients with ICH.