title: Clinical Characteristics and Outcomes of Older Cardiac Resynchronization Therapy Recipients Using a Pacemaker versus a Defibrillator.
abstract: Cardiac resynchronization therapy (CRT) is commonly used to manage heart failure, yet published guidelines do not distinguish between recommendations for pacemakers (CRT-P) and defibrillators (CRT-D) despite significant differences in size, longevity, and cost between these devices. The purpose of this study is to compare the clinical characteristics and outcomes between elderly recipients of CRT-P and CRT-D.
  
  
  
  Data from 512 patients (405 CRT-D, 107 CRT-P) aged ≥75 years with LV ejection fraction ≤35% and QRS duration >120 milliseconds were retrospectively analyzed for baseline characteristics and followed to the primary outcome of all-cause mortality. Cox proportional hazards models were used to adjust for possible confounders. Results were further validated through propensity matching cohorts. Compared to CRT-D recipients, CRT-P patients were older (83 years vs. 81 years, P < 0.001) and had more comorbid conditions (Charlson index = 5 [3-6] vs. 4 [3-5], P = 0.007). During 40.8 months of follow-up, there were 280 deaths. Compared to CRT-D patients, CRT-P recipients had higher unadjusted mortality (HR 1.54, 95% CI 1.15-2.08, P = 0.004). However, this difference lost significance after adjusting for baseline differences between the groups (HR 1.18, 95% CI 0.78-1.77, P = 0.435).
  
  
  
  Higher all-cause mortality in older CRT-P versus CRT-D patients is largely explained by baseline clinical and demographic differences between the two groups, which are likely the drivers of device selection in real-world clinical practice, where the published guidelines remain ambiguous. There is a need for randomized studies to determine optimal CRT device selection.
authors: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors: Muhammad Bilal
authors: MB
authors: Munir
authors: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors: Andrew D
authors: AD
authors: Althouse
authors: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors: Shasank
authors: S
authors: Rijal
authors: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors: Maulin Bharat
authors: MB
authors: Shah
authors: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors: Hussein
authors: H
authors: Abu Daya
authors: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors: Evan
authors: E
authors: Adelstein
authors: Heart and Vascular Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
authors: Samir
authors: S
authors: Saba
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D058406:Cardiac Resynchronization Therapy / Q000009:adverse effects / Q000401:mortality; D058409:Cardiac Resynchronization Therapy Devices; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000295:instrumentation* / Q000401:mortality; D005260:Female; D006333:Heart Failure / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D015999:Multivariate Analysis; D057216:Propensity Score; D016016:Proportional Hazards Models; D011474:Prosthesis Design; D012189:Retrospective Studies; D012307:Risk Factors; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D016277:Ventricular Function, Left
keywords: age; cardiac resynchronization therapy; defibrillator; mortality; pacemaker