The impact of renal function on clinical and biochemical characteristics in advanced heart failure patients

Background: Coexistence of heart failure with reduced ejection fraction (HFrEF) and chronic kidney disease is associated with poor prognosis. We assessed the effect of renal function on exercise capacity and clinical parameters of patients with HF. Material and methods: Forty five patients aged 58.2 ± 10.6 years with stable severe HFrEF were recruited. Patients were divided into 3 groups: group 1 - eGFR: 30-59 ml/min/1.73 m2; group 2 - eGFR: 60-89 ml/min/1.73 m2 and group 3 - eGFR: ≥90 ml/min/1.73 m2. Biochemical analysis, echocardiography, 6-minute walking test and cardiopulmonary stress testing were performed. Results: Patients in group 1 were significantly older than patients in group 3 (60.4 ± 11.1 years vs. 49.25 ± 11.2 years, respectively, p<0.05). Patients in group 2 had significantly higher BMI in comparison to group 3 (29.8 ± 4.4 vs. 25.1 ± 4.2; p<0.05). Interestingly, patients in group 1 had significantly lower peak oxygen uptake (10.2 ± 3.1 ml/kg/min vs. 16.1 ± 3.5 ml/kg/min, p<0.05) and oxygen uptake at anaerobic treshold (7.9 ± 2.4 ml/kg/min vs. 10.7 ± 1.9 ml/kg/min, p<0.05). Conclusions: Diminished renal function in patients with stable, advanced HFrEF may be associated with significantly worse peak VO2 and VO2 in AT.