Impact of Preoperative Temporary Mechanical Circulatory Support on Durable LVAD Outcomes: An Analysis of The Society of Thoracic Surgeons National Intermacs Database.

BACKGROUND

An increasing number of patients undergoing durable left ventricular assist device (LVAD) implantation are supported with temporary mechanical circulatory support (tMCS) devices. The impact of tMCS on post-LVAD outcomes in the contemporary era is poorly described.

OBJECTIVES

This study aims to define characteristics and outcomes in patients undergoing LVAD implantation while on tMCS support from the Society of Thoracic Surgeons Intermacs (Interagency Registry for Mechanically Assisted Circulatory Support) database. The authors hypothesized that mortality rates and adverse events would vary based on tMCS type.

METHODS

Adult patients who underwent implantation of a fully magnetically levitated LVAD from 2020 to 2024 as Intermacs profiles 1-3 were included. Primary outcomes analyzed were 1- and 2-year mortality and rates of stroke. Outcomes were compared in cohorts with no tMCS, intra-aortic balloon pump (IABP), high-flow micro-axial flow pump (HF-MP), and venoarterial extracorporeal membrane oxygenation. A multivariable proportional hazards model was used to determine preoperative and perioperative characteristics associated with patient survival. A propensity score matching (PSM) analysis was performed to compare HF-MP with no tMCS.

RESULTS

A total of 5,787 LVAD patients met inclusion criteria; 3,863 (66.7%) were supported on tMCS at the time of LVAD implantation. The use of the HF-MP increased significantly over the study period (19.1% to 35.1%, P < 0.001) whereas the use of IABP decreased (41.2% to 27.3%, P < 0.001). Overall patient survival was 82.9% and 77.9% at 1 and 2 years, respectively. Patients on extracorporeal membrane oxygenation had the lowest 1- and 2-year survival (70.6% and 67.1%) whereas patients on IABP (85.7% and 81.2%) and HF-MP (82.9% and 77.5%) had survival rates comparable to patients without tMCS therapy (82.4% and 77%, respectively). In the adjusted multivariable model, both HF-MP (HR: 0.71 [95% CI: 0.59-0.84]; P = 0.001) and IABP (HR: 0.74 [95% CI: 0.63-0.86]; P = 0.001) were associated with improved survival compared to no tMCS. In the propensity score matching cohort, rates of survival at 1 and 2 years were 85.2% vs 80.5%, respectively, and 79.9% vs 74.3% for HF-MP, respectively, vs no tMCS therapy (P = 0.009), whereas rates of freedom from stroke at 1 year were similar at 93.1% and 93.9% (P = 0.33), respectively.

CONCLUSIONS

An increasing number of patients undergoing durable LVAD are supported on tMCS at the time of implantation. Use of HF-MP and IABP were associated with improved survival and equivalent rate of stroke compared to no tMCS.