Abstract
BACKGROUND: Chronic heart failure (CHF) is a multifaceted syndrome associated with endothelial dysfunction and increased inflammation. Despite the existing controversies regarding the appropriate training modality, it is widely accepted that supervised cardiac rehabilitation (CR) interventions lead to proinflammatory biomarkers reduction and cellular adhesion molecules in patients with CHF. AIM: The aim of the study was to quantify the effects of 12-week group-based high-intensity aerobic interval training (HIAIT)/modified group-based HIAIT intervention (m-Ullevaal) vs. moderate continuous training (MICT) on serum levels of proinflammatory biomarkers. DESIGN: Single-blind, two-arm, prospective randomized controlled trial conducted on CHF outpatients performing group-based CR interventions throughout a 12-week period. SETTING: The setting of the study was the Medical Center of Outpatient Rehabilitation and Sports Medicine, Plovdiv, Bulgaria. POPULATION: The population included a total of 120 outpatients of both genders, mean age of 63.73±6.68 years, with stable CHF (NYHA classes II to IIIB, were randomly assigned to HIAIT/ m-Ullevaal (N.=60) or to MICT (N.=60) group. METHODS: Functional exercise capacity (FEC) of the eligible subjects was evaluated through 6-minute walk test (6MWT) and peak oxygen uptake. Blood samples were drawn at baseline, after 12 weeks follow-up for analyses of C-reactive protein (CRP), tumor necrosis factor-α (TNFα) and cellular adhesion molecules (CAM). RESULTS: Significant decreases in the serum levels of CRP (P=0.029), TNF-α (P=0.036), and vascular cell adhesion molecule-1 (VCAM-1) (P=0.040), were observed after 48 training sessions in the group-based HIAIT/m-Ullevaal intervention, except for intercellular adhesion molecule-1 (ICAM-1), which was higher in the MICT (P=0.034). FEC was significantly inversely related to CRP (r=-0.72, P<0.05), and the levels of VCAM-1 (r=-0.68, P<0.05). CONCLUSIONS: Both group-based CR interventions (HIAIT/m-Ullevaal and MICT) significantly reduced the serum levels of CRP, TNF- α, ICAM-1 and VCAM in patients with CHF. However, selected proinflammatory biomarkers changes and CAMs favorably decreased in the group-based HIAIT/m-Ullevaal intervention. The responses on serum levels of proinflammatory biomarkers and CAMs are dependent upon the type, intensity, and CR intervention duration. CLINICAL REHABILITATION IMPACT: The group-based high-intensity aerobic interval training reduces significantly the proinflammatory biomarkers and cellular adhesion molecules in patients with chronic heart failure.