Effect of Implantable Cardioverter-defibrillators in Nonischemic Heart Failure According to Background Medical
Adelina Yafasova1, Seiko N Doi1, Jens Jakob Thune2
1Department of Cardiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
Journal of Cardiac Failure
|May 16, 2024
Summary
Lower medication scores in heart failure with reduced ejection fraction (HFrEF) predict higher mortality. Implantable cardioverter-defibrillator (ICD) implantation did not improve survival in nonischemic HFrEF patients, irrespective of their medication score.
Area of Science:
- Cardiology
- Heart Failure Research
- Medical Device Efficacy
Background:
- The Heart Failure Collaboratory (HFC) score assesses guideline-directed pharmacotherapies for heart failure with reduced ejection fraction (HFrEF).
- The modified HFC (mHFC) score was used to evaluate its impact in patients with nonischemic HFrEF.
- This study analyzed data from 1116 patients in the Danish Study to Assess the Efficacy of ICDs in Patients with Nonischemic Systolic HF on Mortality (DANISH).
Purpose of the Study:
- To investigate the association between the modified HFC (mHFC) score and mortality in patients with nonischemic HFrEF.
- To determine if implantable cardioverter-defibrillator (ICD) implantation provides survival benefits across different mHFC score strata.
- To assess the impact of ICDs on all-cause, cardiovascular, and sudden cardiovascular death in this patient population.
Main Methods:
- Patients were categorized based on the dosage of renin-angiotensin-system inhibitors, beta-blockers, and mineralocorticoid receptor antagonists, creating an mHFC score (0-6).
- The study compared outcomes between different mHFC score groups and analyzed the effect of ICD implantation versus control.
- Statistical analysis included adjusted hazard ratios (HR) with 95% confidence intervals (CI) and interaction tests to assess effect modification by mHFC score.
Main Results:
- Lower mHFC scores (1-2) were significantly associated with a higher rate of all-cause death compared to scores of 3-4 (adjusted HR 1.67).
- ICD implantation did not significantly reduce all-cause death (HR 0.89) or cardiovascular death (HR 0.87) overall or within any mHFC score subgroup.
- A significant reduction in sudden cardiovascular death was observed in the ICD group (HR 0.60), but this effect was not modified by mHFC score.
Conclusions:
- Lower adherence to guideline-directed medical therapy, as indicated by lower mHFC scores, is linked to increased all-cause mortality in nonischemic HFrEF.
- ICD implantation does not confer an overall survival advantage in patients with nonischemic HFrEF, irrespective of their medication adherence.
- While ICDs reduced sudden cardiac death, this benefit did not translate into improved overall survival in this specific patient cohort.
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