Renal function and the long term clinical outcomes of cardiac resynchronization therapy with or without defibrillation.

BACKGROUND AND AIMS: Patients with moderate-to-severe chronic kidney disease (CKD) are underepresented in clinical trials of cardiac resynchronization therapy (CRT)-defibrillation or CRT-pacing (CRT-P). We sought to determine whether outcomes after CRT-D are better than after CRT-P over a wide spectrum of CKD.

METHODS AND RESULTS: Clinical events were quantified in relation to pre-implant estimated glomerular filtration rate (eGFR) after CRT-D (n = 410 [39.2%]) or CRT-P (n = 636 [60.8%]) implantation. Over a follow-up period of 3.7 years (median, interquartile range: 2.1-5.7), the eGFR<60 group (n = 598) had a higher risk of total mortality (adjusted hazard ratio [aHR]:1.28; p = 0.017), total mortality or heart failure (HF) hospitalization (aHR:1.32; p = 0.004), total mortality or hospitalization for major adverse cardiac events (MACEs, aHR:1.34; p = 0.002) and cardiac mortality (aHR:1.33; p = 0.036), compared to the eGFR≥60 group (n = 448), after covariate adjustment. In analyses of CRT-D vs CRT-P, CRT-D was associated with a lower risk of total mortality (eGFR≥60 HR: 0.65; p = 0.028; eGFR<60 HR 0.64, p = 0.002), total mortality or HF hospitalization (eGFR≥60: aHR:0.66; p = 0.021; eGFR<60 aHR: 0.69, p = 0.007), total mortality or hospitalization for MACEs (eGFR≥60: aHR:0.70; p = 0.039; eGFR<60 aHR: 0.69, p = 0.005) and cardiac mortality (eGFR≥60: aHR:0.60; p = 0.026; eGFR<60 aHR:0.55; p = 0.003).

CONCLUSION: In CRT recipients, moderate CKD is associated with a higher mortality and morbidity compared to normal renal function or mild CKD. Despite less favourable absolute outcomes, patients with moderate CKD had better outcomes after CRT-D than after CRT-P. This article is protected by copyright. All rights reserved.