Related Experiment Video
Updated: Feb 25, 2026
Cutoff Value of Phase Angle by Bioelectrical Impedance Analysis at Admission as a Prognostic Factor in Patients with Acute Heart Failure
Published on: June 10, 2025
Predicting appropriate shocks in patients with heart failure: Patient level meta-analysis from SCD-HeFT and MADIT II
Emily P Zeitler1, Sana M Al-Khatib1,2, Daniel J Friedman1,2
1Duke University Hospital, Durham, NC, USA.
Insights
Predicting appropriate shocks in primary prevention implantable cardioverter defibrillators (ICDs) is crucial. Higher NYHA class, lower LVEF, no beta-blocker therapy, and single-chamber ICDs predict appropriate shocks.
Area of Science:
- Cardiology
- Medical Devices
- Clinical Trials
Background:
- Primary prevention implantable cardioverter defibrillators (ICDs) lack precise tools for predicting appropriate shocks.
- Identifying predictors of appropriate shocks is essential for optimizing patient selection and device programming.
Purpose of the Study:
- To identify clinical and demographic characteristics that predict appropriate shocks in patients receiving primary prevention ICDs.
Main Methods:
- A meta-analysis of patient-level data from the Multicenter Automatic Defibrillator Implantation Trial II (MADIT II) and the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT).
- Logistic regression analysis was used to identify predictors of appropriate shocks.
Main Results:
- Of 1,463 patients randomized to an ICD, 285 (19%) experienced at least one appropriate shock over a median follow-up of 2.59 years.
- Predictors of appropriate shocks included higher NYHA class, lower left ventricular ejection fraction (LVEF), absence of beta-blocker therapy, and single-chamber ICDs.
Conclusions:
- Higher NYHA class, lower LVEF, no beta-blocker therapy, and single-chamber ICDs are significant predictors of appropriate shocks in primary prevention patients.
- These findings can aid in refining patient selection and management strategies for ICD therapy.
Background:
No precise tools exist to predict appropriate shocks in patients with a primary prevention ICD. We sought to identify characteristics predictive of appropriate shocks in patients with a primary prevention implantable cardioverter defibrillator (ICD).
Methods:
Using patient-level data from the Multicenter Automatic Defibrillator Implantation Trial II (MADIT II) and the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT), we identified patients with any appropriate shock. Clinical and demographic variables were included in a logistic regression model to predict appropriate shocks.
Results:
There were 1,463 patients randomized to an ICD, and 285 (19%) had ≥1 appropriate shock over a median follow-up of 2.59 years. Compared with patients without appropriate ICD shocks, patients who received any appropriate shock tended to have more severe heart failure. In a multiple logistic regression model, predictors of appropriate shocks included NYHA class (NYHA II vs. I: OR 1.65, 95% CI 1.07-2.55; NYHA III vs. I: OR 1.74, 95% CI 1.10-2.76), lower LVEF (per 1% change) (OR 1.04, 95% CI 1.02-1.06), absence of beta-blocker therapy (OR 1.61, 95% CI 1.23-2.12), and single chamber ICD (OR 1.67, 95% CI 1.13-2.45).
Conclusion:
In this meta-analysis of patient level data from MADIT-II and SCD-HeFT, higher NYHA class, lower LVEF, no beta-blocker therapy, and single chamber ICD (vs. dual chamber) were significant predictors of appropriate shocks.
More Related Videos
Related Concept Videos
01:30Heart Failure V: Medical Management
01:30Heart Failure IV: Classification and Diagnostic Evaluation
01:29Heart Failure II: Pathophysiology
01:22Heart Failure VI: Adjunct Therapies
01:29Cardiomyopathy III: Hypertrophic Cardiomyopathy
01:26Heart Failure Drugs: Inhibitors of Renin-Angiotensin System