Abstract 3455: Peri-Procedural Anticoagulation Management of Mechanical Prosthetic Heart Valve Patients within a Thrombophilia Center: A Single-Arm Cohort Study
Background: Mechanical heart valve (MHV) patients often require temporary interruption of chronic warfarin anticoagulation while undergoing an invasive procedure. Objective: To estimate the three-month cumulative incidence of thromboembolism and bleeding among MHV patients receiving peri-procedural anticoagulation management within a Thrombophilia Center.
Methods: In a retrospective single-arm cohort study, consecutive MHV patients referred to the Mayo Clinic Thrombophilia Center for peri-procedural anticoagulation management over the seven-year period, 1997–2003, were followed for three months for thromboembolism, bleeding and vital status. Baseline demographic, clinical and procedure-related characteristics were tested as potential predictors of thromboembolism and bleeding.
Results: Among 556 MHV patients (372 aortic only, 136 mitral only, 48 with multiple valves) undergoing 580 procedures, the three-month cumulative thromboembolism incidence was 0.9% (cerebral ischemia [n=3], unstable angina [n=1], acute myocardial infarction [n=1]; none fatal), while major and minor bleeding occurred in 3.6% (0.2% fatal) and 6.1%, respectively. Low molecular weight heparin (LMWH) was used exclusively as either pre or post-procedure bridging therapy in 66.2% of cases, while 20.4% received no bridging heparin and 6.4% received both pre and post-procedure intravenous unfractionated heparin (UFH). Major bleeding occurred in 2.4%, 3.7%, and 6.1% of cases where no heparin, LMWH only, and any UFH were used post-procedure, respectively (p=0.26).
Conclusions: Among MHV patients receiving peripro-cedural anticoagulation management within a Thrombophilia Center, thromboembolism was uncommon after interruption of anticoagulation for an invasive procedure, and bleeding rates did not differ significantly by absence, presence or type of bridging heparin therapy. Abstract word count: 241