Clinician Approach To Subtherapeutic INR Management In Patients With A Heartmate 3 LVAD: A Regional Subgroup Analysis Of The Momentum 3 (CAP And IDE) Trials

Abstract

Introduction: Patients with Heartmate 3 LVADs are recommended to be on therapeutic anticoagulation consisting of aspirin and warfarin (with a goal INR of 2-3). No specific recommendations exist for the management of subtherapeutic INRs, leading to a variation in management. This study was performed to evaluate clinician behavior in the management of subtherapeutic INRs. Methods: We performed a regional subgroup analysis of the MOMENTUM 3 (CAP and IDE) Trials including 6 centers in the Mid-America Region. All patients implanted with a HeartMate 3 device and discharged alive were included in the analysis. Patients with subtherapeutic INRs (INR \u3c 2) occurring after the index admission underwent manual chart review to determine the management strategies taken by clinicians. Management strategies were separated into three groups: no action taken, isolated adjustment of coumadin, or bridging with IV (heparin, bivalirudin) or parenteral agents (enoxaparin). Results: Among 225 patients included in the analysis, 130 (58%) patients had a total of 235 subtherapeutic INR events. Management strategy was associated with INR (p\u3c0.001; Figure 1). The most common management strategy was a change in coumadin dose (n=100, 42.5%), which occurred at a median (interquartile range [IQR]) INR of 1.70 (1.50-1.80). This was followed by no change in management (n=79, 33.6%), which occurred at a median (IQR) INR of 1.83 (1.60-1.90). Bridging events occurred the least frequently (n=56, 23.8%) at a median (IQR) INR of 1.50 (1.30-1.64). Conclusion: There was a direct relationship between INR and the management strategies of subtherapeutic INRs. At INRs closest to 2, less invasive strategies such as coumadin adjustments or no change were preferred, while bridging strategies (including enoxaparin, heparin, and bivalirudin) were used at lower INRs. The effect of bridging strategies on clinical outcomes including mortality, hospital re-admissions, thromboembolic events, and bleeding are unknown and warrants further evaluation