Assessing the Hemocompatibility of a microaxial, surgically implanted heart pump and safety of anticoagulation with Direct thrombin inhibitors

10119 

Abstract Submission 

Fabian Jimenez Contreras (1), Griffin Stinson (1), Carlos Valdes (1), Omar Sharaf (1), Alex Parker (1), Mohammad Al-Ani (1), Juan Vilaro (1), Mustafa Ahmed (1), Eric Jeng (1)

(1) University of Florida, Gainesville, FL

Fabian Jimenez Contreras    -  Contact Me
University of Florida

Griffin Stinson    -  Contact Me
University of Florida

Carlos Valdes    -  Contact Me
University of Florida

Omar Sharaf    -  Contact Me
University of Florida

Alex Parker    -  Contact Me
University of Florida

Mohammad Al-Ani    -  Contact Me
University of Florida

Juan Vilaro    -  Contact Me
University of Florida

Mustafa Ahmed    -  Contact Me
University of Florida

Eric Jeng    -  Contact Me
University of Florida

Fabian Jimenez Contreras    -  Contact Me
N/A

Objective: The novel microaxial, surgically implanted heart pump (MSIHP) has become one of the most clinically utlized temporary left ventricular assist devices since its FDA approval in late 2019. It is critical to assess the hemocompatibility in pursuit of limiting thrombotic and hemorrhagic events. The safety of anticoagulation (AC) with direct thrombin inhibitors (DTI) during support has not been well described.
Methods: We retrospectively reviewed adult patients (≥18 years old) supported with MSIHP at our institution (May 2020–April 2023) used as bridge to durable support, and/or transplantation. Baseline demographics were collected on all patients. Number of blood products given during Impella support was recorded. Haptoglobin, plasma free hemoglobin, lactate dehydrogenase, and unconjugated bilirubin were collected, at several time points. Rates of in-hospital mortality, 30-day mortality, MSIHP-associated access site complications, and arterial thromboembolic events were recorded.
Results:
A total of 31 patients were supported with Impella 5.5 during the study period. There was no difference in baseline demographics. The duration of support was 28.06±32.56 days. The AC agent was heparin in 27 and DTI in 4 patients. Vascular access was axillary artery in 77% and direct aortic placement in 23%. There was no different in baseline characteristics between groups. In 19% of patients, there was concomitant veno-arterial ECMO support. In-hospital mortality was 33% for heparin and 25% for DTI patients (p=0.739). The mean number of blood products given during support was 7.71±11.76 units; however, 42% of the entire cohort and 75% of the DTI cohort required no transfusions. The heparin group required a greater mean number of transfusions 8.7 vs 1 units (p=0.133). Aggregate total blood products per day of MSIHP support was low at 0.28 units/day. DTI patients had lower rates of total product transfusions per day 0.03 vs 0.32, p-value=0.0329, lower pRBC 0.03 vs 0.22, p-value=0.0332, lower platelets 0.00 vs 0.07, p-value=0.0466 (Table 1). Hemolysis markers were not significantly different pre and post-implant or by AC strategy. Overall thromboembolic event rate was low at 3% and not different among AC strategy.
Conclusion: Support with MSIHP showed high rates of hemocompatibility with many patients requiring no transfusions during their support. In this limited cohort, we found anticoagulation with DTI to be associated with fewer transfusions than heparin.

ECMO/Mechanical Support