Tachycardia therapy outcomes of ischemic versus nonischemic cardiomyopathy on cardiac resynchronization therapy: A propensity score-matched analysis

Abstract

Objective This investigation aimed to investigate differences between dilated cardiomyopathy (DCM) and ischemic cardiomyopathy (ICM) patients treated with cardiac resynchronization therapy with defibrillator (CRT-D) for tachycardia therapy-related outcomes as well as mortality during follow-up of at least 1 year. Methods Seventy-eight patients with DCM (n=42) and ICM (n=36) with implantation or upgradation to CRT-D were included in this study and analyzed for incidence of non-sustained ventricular tachycardia (NSVT), non-sustained ventricular fibrillation (NSVF), defibrillator therapies, anti-tachycardia pacing (ATP), and mortality. Results DCM was the underlying etiology in 42 (53.84%) and ICM in 36 (46.15%). Time to first therapy was numerically longer in DCM than in ICM (9.5 ± 2.4 vs. 7.1 ± 3.2; P-value = 0.088). DCM patients had significantly higher therapy-free survival and mortality compared with ICM patients (OR(95%CI): 0.238(0.155 - 0.424); log-rank P = 0.017) and (OR(95%CI): 0.612(0.254 - 0.924); log-rank P = 0.029). ICM (HR(95%CI): 0.529(0.243 - 0.925); P-value = 0.014) CAD (HR(95%CI): 0.326 (0.122 - 0.691): P-value = 0.003), and NSVT (HR(95%CI): 0.703(0.513 - 0.849): P-value = 0.005) were demonstrated as independent predictors of the primary endpoint of appropriate therapy in CRT-D and ICM (HR(95%CI): 0.421(0.321 - 0.524); P-value = 0.037), chronic kidney disease (CKD; HR(95%CI): 0.289(0.198 - 0.380); P-value = 0.013), and CAD (HR(95%CI): 0.786(0.531 - 0.967); P-value = 0.003) were predictors of mortality. Conclusion The clinical course of ICM and DCM cohorts who were treated with CRT-D differs significantly during follow-up, with increased tachycardia therapy and increased incidence of mortality in ICM patients