Paul Beckers

Combined endurance-resistance training vs. endurance training in patients with chronic heart failure: a prospective randomized study

AIMS This study was designed to compare the effects of combined endurance-resistance training (CT) with endurance training (ET) only on submaximal and maximal exercise capacity, ventilatory prognostic parameters, safety issues, and quality of life in patients with chronic heart failure (CHF). METHODS AND RESULTS Fifty-eight CHF patients (NYHA class II-III) were randomized either to 6 months CT [n = 28, 58 years, left ventricular ejection fraction (LVEF) 26%, VO(2)peak 18.1 mL/kg/min] or ET (n = 30, 59 years, LVEF 23%, VO(2)peak 21.3 mL/kg/min). The increase in steady-state workload (P = 0.007) and the decrease in heart rate at SSW (P = 0.002) were significantly larger in CT- compared with ET-trained patients. Maximal exercise capacity (i.e. VO(2)peak, maximal workload) and work-economy (Wattmax/VO(2)peak) evolved similarly. VO(2)peak halftime was reduced following CT (P = 0.001). Maximal strength in upper limbs increased significantly (P < 0.001) in favour of the CT group. CT also had a beneficial effect on health-related quality of life, i.e. 60% of CT-trained patients vs. 28% of ET-trained patients reported a decrease in cardiac symptoms (OR = 3.86, 95% CI 1.11-12.46, P = 0.03). There were no differences with regard to improved LVEF, evolution of left ventricular dimensions, nor outcome data (mortality and cardiovascular hospital admissions during follow-up). CONCLUSION In CHF patients, CT had a more pronounced effect on submaximal exercise capacity, muscle strength, and quality of life. The absence of unfavourable effects on left ventricular remodelling and outcome parameters is reassuring and might facilitate further implementation of this particular training modality.

Functional Adiponectin Resistance at the Level of the Skeletal Muscle in Mild to Moderate Chronic Heart Failure

Background—Adiponectin is an antiinflammatory, insulin-sensitizing, and antiatherogenic adipocytokine that plays a fundamental role in energy homeostasis. In patients with chronic heart failure (CHF), high circulating adiponectin levels are associated with inverse outcome. Recently, adiponectin expression has been identified in human skeletal muscle fibers. We investigated the expression of adiponectin, the adiponectin receptors, and genes involved in the downstream lipid and glucose metabolism in the skeletal muscle of patients with CHF. Methods and Results—Muscle biopsies (vastus lateralis muscle) were obtained from 13 patients with CHF and 10 healthy subjects. mRNA transcript levels of adiponectin, adiponectin receptors (AdipoR1 and AdipoR2), and downstream adiponectin-related enzymes were quantified by real-time reverse transcriptase polymerase chain reaction. Adiponectin expression in the skeletal muscle of patients with CHF was 5-fold higher than in healthy subjects (P<0.001), whereas AdipoR1 was downregulated (P=0.005). In addition, the expression of the main genes involved in downstream pathway (peroxisome proliferator-activated receptor-&agr; [PPAR-&agr;] and both AMP-activated protein kinase-&agr;1 and -&agr;2 subunits) as well as their target genes in lipid (acyl-coenzyme A dehydrogenase C-14 to C-12 straight chain) and glucose metabolism (hexokinase-2) were significantly reduced in CHF. The strong positive correlation found between AdipoR1 and PPAR-&agr;/AMP-activated protein kinase gene expression was confirmed in PPAR-&agr; null mice, suggesting a cause-and-effect relationship. Immunohistochemical staining confirmed the presence of adiponectin in the skeletal muscle. Conclusions—Despite increased adiponectin expression in the skeletal muscle, patients with CHF are characterized by downregulation of AdipoR1 that is most probably linked to deactivation of the PPAR-&agr;/AMP-activated protein kinase pathway. These facts suggest functional adiponectin resistance at the level of the skeletal muscle in CHF.

Aerobic interval training and continuous training equally improve aerobic exercise capacity in patients with coronary artery disease: the SAINTEX-CAD study.

BACKGROUND Exercise-based cardiac rehabilitation increases peak oxygen uptake (peak VO₂), which is an important predictor of mortality in cardiac patients. However, it remains unclear which exercise characteristics are most effective for improving peak VO₂ in coronary artery disease (CAD) patients. Proof of concept papers comparing Aerobic Interval Training (AIT) and Moderate Continuous Training (MCT) were conducted in small sample sizes and findings were inconsistent and heterogeneous. Therefore, we aimed to compare the effects of AIT and Aerobic Continuous Training (ACT) on peak VO₂, peripheral endothelial function, cardiovascular risk factors, quality of life and safety, in a large multicentre study. METHODS Two-hundred CAD patients (LVEF >40%, 90% men, mean age 58.4 ± 9.1 years) were randomized to a supervised 12-week cardiac rehabilitation programme of three weekly sessions of either AIT (90-95% of peak heart rate (HR)) or ACT (70-75% of peak HR) on a bicycle. Primary outcome was peak VO₂; secondary outcomes were peripheral endothelial function, cardiovascular risk factors, quality of life and safety. RESULTS Peak VO₂ (ml/kg/min) increased significantly in both groups (AIT 22.7 ± 17.6% versus ACT 20.3 ± 15.3%; p-time<0.001). In addition, flow-mediated dilation (AIT+34.1% (range -69.8 to 646%) versus ACT+7.14% (range -66.7 to 503%); p-time<0.001) quality of life and some other cardiovascular risk factors including resting diastolic blood pressure and HDL-C improved significantly after training. Improvements were equal for both training interventions. CONCLUSIONS Contrary to earlier smaller trials, we observed similar improvements in exercise capacity and peripheral endothelial function following AIT and ACT in a large population of CAD patients.

High-Intensity Interval Training in Patients with Heart Failure with Reduced Ejection Fraction

Background: Small studies have suggested that high-intensity interval training (HIIT) is superior to moderate continuous training (MCT) in reversing cardiac remodeling and increasing aerobic capacity in patients with heart failure with reduced ejection fraction. The present multicenter trial compared 12 weeks of supervised interventions of HIIT, MCT, or a recommendation of regular exercise (RRE). Methods: Two hundred sixty-one patients with left ventricular ejection fraction ⩽35% and New York Heart Association class II to III were randomly assigned to HIIT at 90% to 95% of maximal heart rate, MCT at 60% to 70% of maximal heart rate, or RRE. Thereafter, patients were encouraged to continue exercising on their own. Clinical assessments were performed at baseline, after the intervention, and at follow-up after 52 weeks. Primary end point was a between-group comparison of change in left ventricular end-diastolic diameter from baseline to 12 weeks. Results: Groups did not differ in age (median, 60 years), sex (19% women), ischemic pathogenesis (59%), or medication. Change in left ventricular end-diastolic diameter from baseline to 12 weeks was not different between HIIT and MCT (P=0.45); left ventricular end-diastolic diameter changes compared with RRE were −2.8 mm (−5.2 to −0.4 mm; P=0.02) in HIIT and −1.2 mm (−3.6 to 1.2 mm; P=0.34) in MCT. There was also no difference between HIIT and MCT in peak oxygen uptake (P=0.70), but both were superior to RRE. However, none of these changes was maintained at follow-up after 52 weeks. Serious adverse events were not statistically different during supervised intervention or at follow-up at 52 weeks (HIIT, 39%; MCT, 25%; RRE, 34%; P=0.16). Training records showed that 51% of patients exercised below prescribed target during supervised HIIT and 80% above target in MCT. Conclusions: HIIT was not superior to MCT in changing left ventricular remodeling or aerobic capacity, and its feasibility remains unresolved in patients with heart failure. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00917046.

High Intensity Interval Training in Heart Failure Patients with Reduced Ejection Fraction

Background: Small studies have suggested that high-intensity interval training (HIIT) is superior to moderate continuous training (MCT) in reversing cardiac remodeling and increasing aerobic capacity in patients with heart failure with reduced ejection fraction. The present multicenter trial compared 12 weeks of supervised interventions of HIIT, MCT, or a recommendation of regular exercise (RRE). Methods: Two hundred sixty-one patients with left ventricular ejection fraction ⩽35% and New York Heart Association class II to III were randomly assigned to HIIT at 90% to 95% of maximal heart rate, MCT at 60% to 70% of maximal heart rate, or RRE. Thereafter, patients were encouraged to continue exercising on their own. Clinical assessments were performed at baseline, after the intervention, and at follow-up after 52 weeks. Primary end point was a between-group comparison of change in left ventricular end-diastolic diameter from baseline to 12 weeks. Results: Groups did not differ in age (median, 60 years), sex (19% women), ischemic pathogenesis (59%), or medication. Change in left ventricular end-diastolic diameter from baseline to 12 weeks was not different between HIIT and MCT (P=0.45); left ventricular end-diastolic diameter changes compared with RRE were −2.8 mm (−5.2 to −0.4 mm; P=0.02) in HIIT and −1.2 mm (−3.6 to 1.2 mm; P=0.34) in MCT. There was also no difference between HIIT and MCT in peak oxygen uptake (P=0.70), but both were superior to RRE. However, none of these changes was maintained at follow-up after 52 weeks. Serious adverse events were not statistically different during supervised intervention or at follow-up at 52 weeks (HIIT, 39%; MCT, 25%; RRE, 34%; P=0.16). Training records showed that 51% of patients exercised below prescribed target during supervised HIIT and 80% above target in MCT. Conclusions: HIIT was not superior to MCT in changing left ventricular remodeling or aerobic capacity, and its feasibility remains unresolved in patients with heart failure. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00917046.

Exercise acutely reverses dysfunction of circulating angiogenic cells in chronic heart failure.

AIMS Recruitment of endothelial progenitor cells (EPCs) and enhanced activity of circulating angiogenic cells (CACs) might explain the benefits of exercise training in reversing endothelial dysfunction in chronic heart failure (CHF) patients. We studied baseline EPC numbers and CAC function and the effect of a single exercise bout. METHODS AND RESULTS Forty-one CHF patients (mild, n = 22; severe, n = 19) and 13 healthy subjects were included. Migratory activity of CACs was evaluated in vitro and circulating CD34+ and CD34+/KDR+ (EPC) cells were quantified by flow cytometry before and after cardiopulmonary exercise testing (CPET). Circulating stromal cell-derived factor-1alpha (SDF-1alpha) and vascular endothelial growth factor (VEGF) concentrations were measured. Both CAC migration as well as CD34+ cell numbers were significantly reduced in CHF, whereas CD34+/KDR+ cells were not different from controls. Endothelial dysfunction was related to impaired CAC migration (r = 0.318, P = 0.023). Cardiopulmonary exercise testing improved CAC migration in severe (+52%, P < 0.005) and mild CHF (+31%, P < 0.005), restoring it to levels similar to controls. Following CPET, SDF-1alpha increased in healthy controls and mild CHF (P < 0.005). Vascular endothelial growth factor, CD34+, and CD34+/KDR+ cell numbers remained unchanged. CONCLUSION The present findings reveal a potent stimulus of acute exercise to reverse CAC dysfunction in CHF patients with endothelial dysfunction.

The effect of endurance training on exercise capacity following cardiac resynchronization therapy in chronic heart failure patients: a pilot trial

Background Both endurance training (ET) and cardiac resynchronization therapy (CRT) improve quality of life (QOL) and exercise tolerance in patients with advanced chronic heart failure (CHF). Design A randomized intervention trial to study the effect on exercise capacity of ET in addition to CRT in patients with CHF and dyssynchrony. Methods Seventeen patients (eight men, aged 59 ± 9 years) with CHF and dyssynchrony were randomized to CRT with (n = 8) or without (n = 9) ET and compared with two matched control CHF groups (standard care with ET: n = 9, standard care only: n = 10). At baseline and after 5 months, exercise tolerance, left ventricular (LV) remodelling, QOL and NT-pro brain natriuretic peptide (NT-proBNP) levels were assessed. Results Peak oxygen consumption (VO2peak), maximal workload (Wattmax), circulatory power, LV ejection fraction, dyssynchrony and QOL improved in both CRT groups. However, the increase in VO2peak (+ 40% versus +16%, P = 0.005), Wattmax (+ 43% versus +13%, P = 0.0005), and circulatory power (+ 74% versus + 32%, P = 0.01), was significantly greater in the trained versus the untrained CRT patients. Comparison of the four patient groups confirmed the cumulative effects of CRT plus ET. Conclusions ET in resynchronized CHF patients is feasible and further enhances exercise tolerance. Patients with severe CHF should be prescribed an exercise training programme after implantation in order to maximize the expected benefit. Eur J Cardiovasc Prev Rehabil 14: 99-106

Unraveling new mechanisms of exercise intolerance in chronic heart failure. Role of exercise training

Despite remarkable progress in the therapeutic approach of patients with chronic heart failure (CHF), exercise intolerance remains one of the hallmarks of the disease. During the past two decades, evidence has accumulated to underscore the key role of both endothelial dysfunction and skeletal muscle wasting in the process that gradually leads to physical incapacity. Whereas reverse ventricular remodeling has been attributed to aerobic exercise training, the vast majority of studies conducted in this specific patient population emphasize the reversal of peripheral abnormalities. In this review, we provide a general overview on underlying pathophysiological mechanisms. In addition, emphasis is put on recently identified pathways, which contribute to a deeper understanding of the main causes of exercise tolerance and the potential for reversal through exercise training. Recently, deficient bone marrow-related endothelial repair mechanisms have received considerable attention. Both acute exercise bouts, as well as exercise training, affect the mobilization of endothelial progenitor cells and their function. The observed changes following exercise training are believed to significantly contribute to improvement of peripheral endothelial function, as well as exercise capacity. With regard to skeletal muscle dysfunction and energy deprivation, adiponectin has been suggested to play a significant role. The demonstration of local skeletal muscle adiponectin resistance may provide an interesting and new link between the insulin resistant state and skeletal muscle wasting in CHF patients.

Circulating CD34+/KDR+ endothelial progenitor cells are reduced in chronic heart failure patients as a function of Type D personality

The aim of the present study was to assess whether EPC (endothelial progenitor cell) number/function might be an explanatory factor for the observed relationship between Type D personality (a joint tendency towards negative affectivity and social inhibition) and poor cardiovascular prognosis. We also assessed whether the effect of a single exercise bout on EPC number/function was affected by Type D personality. A total of 35 sedentary men with CHF (chronic heart failure; left ventricular ejection fraction <or=45%) underwent CPET (cardiopulmonary exercise testing) and personality assessment with the 14-item Type D scale. CD34+/KDR (kinase insert domain-containing receptor)+ cells were quantified by flow cytometry before and immediately after CPET. Migration of early EPC towards VEGF (vascular endothelial growth factor) and SDF-1alpha (stromal-cell-derived factor-1alpha) was investigated. Type D (n=10) and non-Type D (n=25) patients were comparable with regards to demographics, disease severity and Framingham risk factor score. Circulating EPC numbers were reduced by 54% in Type D compared with non-Type D patients (0.084+/-0.055 and 0.183+/-0.029% of lymphocytes respectively; P=0.006). Exercise led to a 60% increase in EPC in Type D patients, whereas the EPC number remained unchanged in the non-Type D group (P=0.049). Baseline migratory capacity was related to disease severity, but was not different between Type D and non-Type D patients. Exercise induced a highly significant enhancement of migratory capacity in both groups. In conclusion, reduced EPC numbers might explain the impaired cardiovascular outcome in Type D patients. The larger increase in circulating EPCs observed in these patients suggests that acute exercise elicits a more pronounced stimulus for endothelial repair.

Optimising exercise training in prevention and treatment of diastolic heart failure (OptimEx-CLIN): rationale and design of a prospective, randomised, controlled trial.

Background Heart failure with preserved left ventricular ejection fraction (HFpEF) currently affects more than seven million Europeans and is the only cardiovascular disease increasing in prevalence and incidence. No pharmacological agent has yet been shown to improve symptoms or prognosis. The most promising way to improve pathophysiology and deprived exercise-tolerance in HFpEF patients seems to be exercise training, but the optimal approach and dose of exercise is still unknown. Objectives The major objective of the optimising exercise training in prevention and treatment of diastolic heart failure study (OptimEx-CLIN) is to define the optimal dose of exercise training in patients with HFpEF. In order to optimise adherence, supervision and economic aspects of exercise training a novel telemedical approach will be introduced and investigated. Study design In a prospective randomised multi-centre study, 180 patients with stable symptomatic HFpEF will be randomised (1:1:1) to moderate intensity continuous training, high intensity interval training, or a control group. The training intervention includes three months supervised followed by nine months of telemedically monitored home-based training. The primary endpoint is change in exercise capacity, defined as change in peak oxygen uptake (VO2peak) after three months, assessed by cardiopulmonary exercise testing. Secondary endpoints include diastolic filling pressure (E/e′) and further echocardiographic and cardiopulmonary exercise testing (CPX) parameters, biomarkers, quality of life and endothelial function. Training sessions and physical activity will be monitored and documented throughout the study with accelerometers and heart rate monitors developed on a telemedical platform for the OptimEx-CLIN study. Inclusion of patients started in July 2014, first results are expected in 2017.