2026 Southeastern Residency Conference

Title: Impact of Anticoagulation Strategies on Thrombotic Events in Patients with Durable Left Ventricular Assist Devices (IMPACT-LVAD)
Authors: Asya Bookal, Danielle McPherson, Michelle Dillon

Background/Objective: Advanced heart failure (HF) poses a significant and increasing burden, affecting around 15% of all HF patients. Treatment options for patients with advanced HF include durable left ventricular assist devices (LVAD) which improve 2-year survival by 80% and may be used either as a bridge to heart transplantation or as destination therapy. There are currently three generations of LVADs; newer generations like the HeartMate 3 (HM3) device have a continuous and fully magnetic levitation which improves hemocompatibility and thus safety. Although newer generation devices have less risk of thrombosis, all devices inherently have some; therefore, long-term anticoagulation is recommended. In the acute perioperative period, the competing risks of bleeding and thrombosis must be balanced, which may delay anticoagulation initiation. Institutional anticoagulation strategies have also been impacted post ARIES-HM3 trial. This study aims to evaluate the incidence of thrombotic and bleeding events after HM3 implantation. 

Methods: This retrospective review includes adults who underwent durable LVAD placement with a HM3 device at AdventHealth Orlando between August 1, 2022 and August 31, 2025. Patients were excluded if they received an alternate device, required additional mechanical circulatory support with device placement, had delayed chest closure, or history of heparin-induced thrombocytopenia (HIT). The primary endpoint is incidence of thrombotic events after HM3 implantation, defined as deep vein thrombosis (DVT), pulmonary embolism (PE), cardioembolic stroke, thrombus induced acute coronary syndrome (ACS), or device-associated thrombus. Secondary endpoints include bleeding defined by the Mechanical Circulatory Support Academic Research Consortium (MCS-ARC), time to therapeutic anticoagulation, anticoagulation time in the therapeutic range (TTR), and time to initiation of warfarin.  

Results: Of 124 patients screened, 88 were included in the study. Patients were on average 58 years old (SD ±13), 65 (74%) were male, 42 (48%) had history of atrial fibrillation, 13 (15%) had history of DVT/PE, 44 (50%) were on therapeutic anticoagulation, and 29 (33%) required MCS preoperatively. Bleeding events occurred in 24 (27%) patients with 12 (50%) being type 2 requiring intervention, but no type 5 fatal bleeding events occurred. Fourteen (16%) patients experienced a thrombotic event with 12 (86%) being upper extremity DVT, 1 (7%) cardioembolic stroke, and 1 (7%) pulmonary embolism. Patients were split into aspirin use pre- and post- ARIES-HM3 trial with all 21 (100%) pre-trial receiving aspirin and 35 (52%) post-trial receiving aspirin. Median time to warfarin initiation was 5 days (IQR 3, 7), time to therapeutic INR was 6 days (IQR 4, 7), and time to therapeutic aPTT was 12 hours (IQR 6, 15). Median TTR for warfarin days 6-10 was 60% (IQR 35, 1), median TTR for parenteral anticoagulation days 1-5 was 49% (IQR 33, 64), and time in subtherapeutic aPTT range was 46% (IQR 24, 60).

Conclusions: Patients who underwent HM3 implantation experienced low rates of thrombotic events despite changes in anticoagulation strategies and did not experience fatal bleeding.