Baseline creatinine level and long-term outcomes in patients with heart failure undergoing cardiac resynchronization therapy

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background Renal dysfunction has been shown as an independent predictor of mortality in patients with heart failure (HF). However, data on the long-term outcomes of cardiac resynchronization therapy (CRT) in patients with chronic kidney disease is scarce due to underrepresentation of such patients in clinical trials on CRT. Aim To determine outcome and mortality predictors in patients with HF and elevated creatinine level treated with cardiac resynchronization therapy. Methods Study population consisted of 1059 consecutive patients with CRT implanted between 2002 and 2019 in a tertiary care university hospital, in a densely inhabited, urban region of Poland (949 subjects [89.6%] with CRT-D; 110 patients with CRT-P [10.4%]; 832 men [78.6%]). Results The median creatinine level before CRT implantation was 96 umol/L (10th and 90th percentile: 67-160). We divided all CRT patients into quartiles per creatinine level: I <79 umol/L, II 79 to less than 96 umol/L, III 96 to less than 118 umol/L, and IV ≥118 umol/L. During the median follow-up of 1661 days (10th and 90th percentile: 323-3995), mortality rates for quartiles I-IV were 36.8, 44.9, 60.1, and 71.7%, respectively (P<0.05) [Figure 1]. The creatinine level ≥118 umol/L (quartile IV) appeared to be an independent risk factor for death (HR 1.004, 95%CI 1.003-1.006, P<0.001). On multivariable analysis, lower left ventricular ejection fraction (HR 0.97, 95%CI 0.95-0.99, P=0.04), higher NT-proBNP level (HR 1.00, 95%CI 1.0001-1.0005, P=0.04), and diabetes treated with insulin (HR 1.64, 95%CI 1.07-2.53, P=0.02) were independent risk factors for death in quartile IV. The mortality rate in those with creatinine level ≥118 umol/L and left ventricular ejection fraction ≤ 20% was 88% during the observation. Conclusions Compared to patients without renal dysfunction prior to CRT implantation, mortality rates of those with creatinine level ≥118 umol/L are significantly higher and reach 70% in 4.5 years of median observation. Almost 9 out of 10 CRT recipients with creatinine level ≥118 umol/L and left ventricular ejection fraction ≤ 20% die within 4.5 years since CRT implantation. Figure 1. Kaplan-Meier curves for survival of patients treated with cardiac resynchronization therapy as a function of creatinine level