# Outcomes in Heart Failure With Improved Ejection Fraction Following Implantable Cardioverter-Defibrillator Placement for Primary Prevention

## TL;DR

Patients with improved heart function after ICD/CRT implantation had fewer hospitalizations and lower mortality compared to those with ongoing heart failure.

## Contribution

This study evaluates outcomes in heart failure patients with improved ejection fraction following ICD/CRT implantation using the 2022 AHA/ACC definition.

## Key findings

- HFimpEF patients had significantly lower one-year and overall hospitalization rates compared to HFrEF patients.
- Mortality was lower in the HFimpEF group, though not statistically significant.
- Lower BNP levels predicted improved ejection fraction and reduced mortality.

## Abstract

Background

Limited data exist on outcomes in heart failure with improved ejection fraction (HFimpEF) following implantation of cardiac devices, such as implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy (CRT). In this contemporary analysis, we utilize the most current American Heart Association (AHA)/American College of Cardiology (ACC) 2022 definition of HFimpEF to evaluate hospitalization and mortality in this population.

Methods

This retrospective study analyzed patients who received ICD or CRT for primary prevention at a non-tertiary hospital between 2019 and 2022. Data were extracted from the Device Implant Registry, assessing demographics, clinical parameters, echocardiography, and device type. Improvement in ejection fraction (EF) was assessed using a follow-up echocardiogram performed at least six months after device implantation. The outcomes measured included the one-year and overall (3.6 years) rates of hospitalization and mortality from the date of ICD/CRT insertion to October 1, 2024.

Results

Our study comprised 54 patients with a repeat echocardiogram after at least six months post-ICD/CRT placement to assess left ventricular ejection fraction (EF). Those with HFimpEF had fewer one-year admissions (22.2%) compared to those with persistent heart failure with reduced EF (HFrEF) (48.2%) (p < 0.05). Overall hospitalization rates were also significantly lower (59.3%) in HFimpEF versus 85.19% in HFrEF (p < 0.05). Heart failure accounted for 50% of the cardiac-related hospitalizations. Mortality rates were reduced (14.8%) in the HFimpEF group compared with 29.63% in HFrEF, but there was no significant statistical difference between the groups. A lower brain natriuretic peptide (BNP) is predictive of both improved EF (p < 0.01) and decreased mortality (p < 0.01).

Conclusions

Patients with myocardial recovery post-ICD/CRT have better prognoses than those with persistent HFrEF. Uncontrolled heart failure remains the predominant factor contributing to hospitalization after device implantation among our cohort. Implementing an outpatient standardized clinical interval summary that incorporates scheduled BNP assessment may represent a cost-effective strategy to enhance the care of patients with HFimpEF in non-tertiary healthcare.