Residual Heart Failure on Mechanically Assisted Circulation: A Call to Action

Validation of the HeartMate 3 survival risk score in a large left ventricular assist device center

OBJECTIVE

The HeartMate 3 survival risk score was recently validated in the Multicenter study Of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3 to predict patient-specific survival in HeartMate 3 left ventricular assist device candidates. The HeartMate 3 survival risk score stratifies individuals into tertiles according to survival probability.

METHODS

We performed a single-center retrospective review of all HeartMate 3 left ventricular assist device recipients between September 2017 and August 2022. Baseline characteristics were collected from the electronic medical records. HeartMate 3 survival risk scores were calculated for all eligible patients. One- and 2-year Kaplan-Meier survival analyses were conducted. A univariate and multivariable Cox regression model was used to identify predictors.

RESULTS

A total of 181 patients were included in this final analysis. The median age was 62 years, 83% were male, and 26% were Interagency Registry for Mechanically Assisted Circulatory Support Profile 1. The mean HeartMate 3 survival risk score for the entire cohort was 2.66 ± 0.66. Two-year survivals in the high, average, and low survival groups were 93.5% ± 3.2%, 81.6% ± 7.4%, and 82.0% ± 6.6%, respectively. As a continuous variable, the unadjusted HeartMate 3 survival risk score was a significant predictor of mortality (hazard ratio, 2.20; 95% CI, 1.08-4.45; P = .029). The areas under the curve were 0.70 and 0.66 at 1 and 2 years, respectively. We were unable to demonstrate the discriminatory ability of the HeartMate 3 survival risk score using the original stratification, but we found significantly increased survival in the high survival group using a binary cutoff (hazard ratio, 4.8; 95% CI, 1.01-20.9; P = .038).

CONCLUSIONS

The unadjusted HeartMate 3 survival risk score was associated with postimplant survival in patients outside of the Multicenter study Of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3 but did not remain an independent predictor after adjusting for ischemic etiology and severe diabetes. The HeartMate 3 survival risk score was able to identify patients at high survival using a binary cutoff, but we were unable to demonstrate its discriminatory ability among the previously published risk tertiles.

Treatment Strategies and Outcomes of Right Ventricular Failure Post Left Ventricular Assist Device Implantation: An INTERMACS Analysis

Right heart failure (RHF) management after left ventricular assist device (LVAD) implantation includes inotropes, right ventricular mechanical support, and heart transplantation. The purpose of this study is to compare different RHF treatment strategies in patients with a magnetically levitated centrifugal LVAD. A total of 6,632 Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) patients from 2013 to 2020 were included. Of which, 769 (69.6%) patients (group 1) were supported with inotropes (≥14 days post-LVAD implantation), 233 (21.1%) patients (group 2) were supported with temporary right ventricular assist device (RVAD) that was implanted during LVAD implant, 77 (7.0%) patients (group 3) with durable centrifugal RVAD implanted during the LVAD implant, and 26 (2.4%) patients (group 4) were supported with RVAD (temporary or permanent), which was implanted at a later stage. Groups 1 and 4 had higher survival rates in comparison with group 2 (hazard ratio [HR] = 0.513, 95% confidence intervals [CIs] = 0.402-0.655, p < 0.001, versus group 1) and group 3 (HR = 0.461, 95% CIs = 0.320-0.666, p < 0.001, versus group 1). Patients in group 3 showed higher heart transplantation rates at 12 and 36 months as compared with group 1 (40.4% and 46.6% vs. 21.9% and 37.4%, respectively), group 2 (40.4% and 46.6% vs. 25.8% and 39.3%, respectively), and group 4 (40.4% and 46.6% vs. 3.8% and 12.0%, respectively). Severe RHF post-LVAD is associated with poor survival. Patients with LVAD who during the perioperative period are in need of right ventricular temporary or durable mechanical circulatory support constitute a group at particular risk. Improvement of devices tailored for right ventricular support is mandatory for further evolution of the field.