Effectiveness of Implantable Cardioverter-Defibrillator Therapy for Primary Prevention in Patients with Nonischemic Heart Failure with Reduced Ejection Fraction.
Luis E Rohde, Leandro I Zimerman, Lídia Z Moura et al.
✦ AI-curated · Sources linked
In 30 seconds
This rapid systematic review and meta-analysis assessed primary-prevention implantable cardioverter-defibrillator (ICD) therapy in patients with nonischemic heart failure with reduced ejection fraction, drawing on 18 publications from six pivotal randomized controlled trials. ICD therapy was associated with lower sudden cardiac death (RR 0.41; 95%CI 0.26-0.65) and cardiovascular mortality (RR 0.75; 95%CI 0.59-0.95), both supported by high-certainty evidence. The primary analysis found no statistically significant reduction in all-cause mortality (RR 0.88; 95%CI 0.72-1.07). A subgroup of studies with follow-up < 6.8 years showed lower all-cause mortality.
Key findings
- ICD therapy reduced sudden cardiac death: RR 0.41; 95%CI 0.26-0.65, with high-certainty evidence.
- Cardiovascular mortality was lower with ICD therapy: RR 0.75; 95%CI 0.59-0.95, with high-certainty evidence.
- The primary analysis found no significant all-cause mortality difference: RR 0.88; 95%CI 0.72-1.07.
- In studies with follow-up < 6.8 years, subgroup analysis showed lower all-cause mortality: RR 0.69; 95%CI 0.52-0.92.
Why it matters
The findings distinguish reductions in sudden cardiac death and cardiovascular mortality from the absence of a significant all-cause mortality benefit in the primary analysis. This helps frame the potential benefits of primary-prevention ICD therapy without implying that it improves overall survival for every patient with nonischemic HFrEF.
What to keep in mind
The primary all-cause mortality analysis did not show a statistically significant difference; the reported benefit in that outcome came from a subgroup analysis.