Benefits of cardiac rehabilitation in cardio-renal patients: a retrospective study of heart failure 578 patients with reduced ejection fraction

Type of funding sources: None.

Chronic kidney disease (CKD) is common during the course of heart failure (HF). It is often associated with worse prognosis and complicates the management of these patients. Moreover CKD is accompanied by sarcopenia, which may limit the benefits of cardiac rehabilitation (CR) in the cardio-renal syndrome (CRS).

The aim of this study was to evaluate the effect of CR on the physical capacities according to the stage of CKD assessed by a cardiorespiratory exercise test (CPET) at the beginning and end of the program in patients with reduced ejection fraction (HFrEF).

This is a retrospective study, conducted from January 2004 to December 2019 on 573 consecutive HFrEF patients, who benefited from a 4-week CR.

Patients were divided into 4 groups according to their GFR (group (G) 1 >= 60; G2: 45-59; G3: 30-44; G4 < 30 ml/min/1.73m². We compared these groups (ANOVA test) and looked with multivariate analysis for factors associated with an improvement in peak VO2 (VO2p).

Of the general population, 38% of patients had a GFR<60ml/min. After CR, there was an improvement in VO2p (15.4 vs 17.8, p=0.00009), SV1 (10.5 vs12.4, p=0.0001), watts (77 vs 93.6, p<0.000), and BNP (688 vs 488, p=0.00002). With decreasing stages of CKD, there was a deterioration in VO2p (16.2, 14.3, 13.6, 13.3), SV1 (10.9, 10.1, 9.3, 9.1), watts (83.4, 69.2, 66.3, 55.2), and an increase BNP levels (570, 885, 771, 1235 pg/ml). The improvement in VO2p, SV1, watts, BNP was statistically significant for all stages of CKD except in group 4 for VO2p (13.3 vs 14.4, p=0.1).

In multivariate analysis factors predicting improvement in VO2p were baseline VO2p and maximal systolic blood pressure.

CR is beneficial in HFrEF patients with CKD. CRS should not be a barrier to prescribing CR.