Perspective:

Despite almost two decades of primary prevention ICD therapy being offered to patients with nonischemic cardiomyopathy, there remains some uncertainty about the magnitude of benefit in these patients, especially those who are also the recipients of the CRT. Most notably, the DANISH trial failed to demonstrate statistically significant improvement in all-cause mortality in patients with nonischemic cardiomyopathy undergoing ICD implantation. The authors of the present study used previously unreleased data from the COMPANION trial and provided an analysis of outcomes of nonischemic patients with CRT-D versus CRT-P. The startling lack of all-cause mortality reduction of CRT-D versus CRT-P in patients with ischemic cardiomyopathy appears to be related to older age and greater number of vascular comorbidities as well as noncardiac deaths in this cohort. The authors of the present analysis explain the differences between DANISH- and COMPANION-derived outcomes by highlighting higher rates of more advanced heart failure in the COMPANION trial. Of course, the standard heart failure regimen of neither DANISH nor COMPANION trial included sacubitril/valsartan and sodium-glucose cotransporter-2 inhibitors, and it is not known how these recent pharmacological advances may differentially affect outcomes of patients with CRT-D versus CRT-P.