Impact of optimal medical therapy with SGLT2 inhibitor on left ventricular ejection fraction recovery in a pre vs post guideline era in HFrEF patients fitted with a wearable cardioverter defibrillator

Introduction

Patients with heart failure and severely reduced left ventricular ejection fraction (LVEF) ≤ 35% (HFrEF) are at elevated risk for arrhythmias and sudden cardiac death. To evaluate potential recovery in LVEF under optimal guideline-directed medical therapy (GMDT) after initial diagnosis, patients can be provided with a wearable cardioverter-defibrillator (WCD) within the first 3 months to bridge this time. According to the ESC-HF guideline (HF-GL) introduced in 2021, GMDT consists of the “fantastic four” including Sodium-Glucose-linked-transporter-2 inhibitors (SGLT-2i) being a cornerstone of this therapy. Objective of this analysis was to evaluate the change/adherence in GMDT therapy before/after HF-GL including the rate of LVEF recovery to >35% in a well-defined WCD patient cohort.

Methods 

We retrospectively analyzed all patients in our tertiary care center fitted with a WCD from 03/2018 until 03/2024. 54 patients were included before and 66 patients after release of the most recent HF-GL in 09/2021. Baseline (BL) characteristics can be seen in table 1. For every patient we calculated Quad Medical Score (QMS). QMS is an objective measure to evaluate guideline adherence in heart failure therapy. The score is calculated on the presence of all four substance classes. Higher values represent higher guideline adherence. Further, LVEF was assessed at baseline and 3 months (FU) after the initiation of GDMT evaluating the change in LVEF before/after HF-GL implementation.

Results 

A total of 120 patients were analyzed: Men 80% (n= 96), ischemic heart disease (ICM) in 51% of included patients. Median LVEF overall at baseline was 24.4% and after a median of 84 days of follow up (FU)LVEF improved to 33.9% with ΔLVEF of +9.6%. 

Patients treated with WCD before HF-GL implantation LVEF was 24.0% at baseline and 31.4% with ΔLVEF of +7.5% at FU, while patients treated after HF-GL implementation had mean LVEF 24.0% at baseline and 35.1% (FU) resulting in a ΔLVEF of 10.1% (p<0.001 BL vs. FU). Analysis of change of LVEF at BL and FU revealed a significant difference between the groups only for the ICM cohort (p<0.05 before vs. after HF-GL; figure 1A), while for all entities (ICM + non-ICM) statistical significance was not reached. Mean QMS in all patients before and after guideline initiation was 6.2 vs. 7.6, respectively (p<0.001). QMS distribution before and after HF-GL is shown in figure 1B. 

Conclusion 

In patients with HFrEF equipped with a WCD significantly more patients were prescribed with a SGLT-2 inhibitor after HF-GL update 2021, these patients showed higher QMS and significantly higher rate of LVEF recovery. These results highlight the potential impact of the recent HF-GL including SGLT-2 inhibitors as addition to GDMT especially in ICM patients further underlying the rationale for WCD use in these patients allowing LVEF recovery while providing SCD protection. 

Table 1: Baseline characteristics 

Figure 1: