Primary Prevention Implantable Cardioverter Defibrillators in Patients With Nonischemic Cardiomyopathy
Diminishing Returns With Advancing Age?
This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.
Article, see p 1772
Early randomized clinical trials of primary prevention implantable cardioverter defibrillators (ICDs) in patients with nonischemic cardiomyopathy failed to establish survival benefit from this therapy; however, those trials were too small to provide definitive results.1,2 When the SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial) was published in 2005, it was practice changing. SCD-HeFT showed that primary prevention ICDs significantly improve the survival of patients with a left ventricular ejection fraction ≤35% attributable to ischemic or nonischemic cardiomyopathy and New York Heart Association class II or III heart failure symptoms despite optimal medical therapy.3 Patients with nonischemic cardiomyopathy constituted about half of the 2521 total enrolled patients in SCD-HeFT.3 The results of SCD-HeFT formed the basis of a class I guideline recommendation for primary prevention ICDs in patients with New York Heart Association class II or III heart failure symptoms and a left ventricular ejection fraction ≤35% attributable to nonischemic cardiomyopathy,4,5 a recommendation that has not changed since 2005.
The role of primary prevention ICDs in patients with nonischemic cardiomyopathy was called into question with the recent publication of the DANISH trial (Danish Study to Assess the Efficacy of ICDs in Patients with Nonischemic Systolic Heart Failure on Mortality).6 This trial enrolled patients with New York Heart Association class II or III heart failure symptoms (or New York Heart Association class IV if cardiac resynchronization therapy [CRT] was planned) with a left ventricular ejection fraction ≤35% attributable to nonischemic cardiomyopathy and an increased level of N-terminal pro–brain natriuretic peptide. Participants were required to be on guideline-directed medical therapy.6 The DANISH trial showed a reduction in sudden …