P0807THE IMPACT OF GLOMERULAR FILTRATION RATE IN HEART FAILURE PATIENTS WITH CARDIAC IMPLANTABLE DEVICES - MYTH OR FACT?
Authors: Rodrigues Natacha , N Ferreira Afonso , António Pedro , Carrington Mafalda , De Sousa João , Lopes José António , Guerra José , J Pinto Fausto , Marques Pedro 
Published: June 2020

Abstract

Background and Aims
Heart Failure (HF) and chronic kidney disease (CKD) are both epidemic, frequently simultaneous and sharing well knowned risk factors. Implantable devices can improve quality of life and reduce mortality in a selected population. Data derived from meta-analyses show both survival benefit in CKD patients receiving devices and increased risk of death in device patients with CKD. Little is Known about the impact of glomerular filtration rate (GFR) across the different stages of CKD in the vital prognoses of HF patients submitted to cardiac resynchronization therapy (CRT) or implantable cardiac defibrillator (ICD) implants.
To evaluate the impact of CKD in all-cause mortality in HF patients who implanted a CRT or ICD.

Method
Prospective single-center study of patients who implanted CRT or ICD between 2015 and 2019. Clinical characteristics were evaluated at baseline and mortality was assessed using the national registry. CKD was evaluated according to the GFR by CKD-EPI equation according to the KDIGO guidelines. We performed univariate and multivariate analysis to compare clinical characteristics of patients who died and who survived using the Cox regression and Kaplan-Meier methods. For the predictor GFR levels, and according to the KDIGO classification, we assessed the best cut-off value for mortality using the area under the ROC curve (AUC) method.

Results
From 2015-2019, 974 devices were implanted, 414 ICDs and 560 CRTs (23.3% female, 67.6±12.1, follow-up duration 26.4±16.5 months). A total of 161 patients (16.5%) died during follow-up. GFR at the time of device implant was significantly lower in patients who died compared to those who survived (49.7 vs 67.3ml/min/1.73m2, p&lt;0.001). When evaluating predictors for all-cause mortality by multivariate analysis, GFR at the time of device implant was an independent predictor of mortality, even when adjusted for age, gender, arterial hypertension and diabetes (HR 1.12; 95% CI 1.04-1.16, p&lt;0.001). The best GFR cut-off value to predict mortality with a 69% sensitivity and 65% specificity was 75ml/min/1.73m2 (AUC 0.70). Patients with a GFR &lt; 75ml/min/1.73m2 at the time of implant have a 2.5-fold higher risk of death (HR 2.5; 95% CI 1.6-3.9, p&lt;0.001). Risk of death significantly increases along GFR decline, almost doubling each stage, with 2.7 for stage 3a (p=0.2), 5.5 for stage 3b, 9.5 for stage 4 and 14.7-fold higher risk of death for stage 5 (p&lt;0.001).

Conclusion
In our cohort of HF patients who underwent CRT or ICD implant, glomerular filtration rate was an independent predictor for all-cause mortality. Additionally, GFR&lt;75ml/min/1.73m2 at the time of device implant increased by 2.5-fold the risk of death, the risk doubles for each CKD stage increase, reaching a dramatic 14.7- fold higher risk of death for stage 5 patients.
CKD should not postpone device implant, as its deterioration significantly increases the risk of death.