IMPACT OF CHRONIC KIDNEY DISEASE ON HEART FAILURE SEVERITY IN HYPERTENSION AND ATRIAL FIBRILLATION PATIENTS

Abstract

Objective: Given the frequent association of chronic kidney disease (CKD) to cardiovascular disorders and the coexistence of heart failure (HF) with atrial fibrillation (AF), especially in elderly, hypertension being a contributor, our main objective was to assess the effect of kidney dysfunction on the heart failure progression in hypertension and atrial fibrillation patients. Design and method: We conducted a retrospective analytic-observational study that included 258 AF patients, mean age 73.48 yr (SD = 10.4), 51.6% females. In order to classify the CKD, we divided the study population in two groups based on the estimated glomerular filtration rate (eGFR): higher or equal than 60, respectively below 60 ml/min/1.73 square meters, comparing the estimations of Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations. We used the NYHA classification to identify the HF severity. Results: Of all patients, according to the presence or absence of the hypertension, 210 patients (81.4%) presented high blood pressure values. In terms of the eGFR using the MDRD equation, 117 patients presented a value higher or equal than 60 ml/min/1.73 square meters, while 93 had an eGFR below 60 ml/min/1.73 square meters. The median value of NYHA class was 3 in both groups (SD = 1.03; 0.96) and there was no statistical significance (p = 0.13) between them. By comparison, estimation using the CKD-EPI equation, indicated a statistically significant difference (p = 0.03), 109 patients presented higher than 60 ml/min/1.73 square meters and 101 patients were below this cut off value even though the median NYHA class was 3 as well (SD = 1.04; 0.94). Conclusions: These results reinforce the well-known superiority in the accuracy of the CKD-EPI equation. But, in terms of the influence of renal dysfunction severity on the heart failure severeness, our results suggest that decreasing in the eGFR is not correlated with the progression of the heart failure in AF patients. However, given the severity of complications and importance of proper treatment in atrial fibrillation, the development of an estimation equation that relates to the presence of atrial fibrillation should be considered.