Aerobic exercise effect on prognostic markers for systolic heart failure patients: a systematic review and meta-analysis.

From previous systematic reviews and meta-analyses, there is consensus about the positive effect of exercise training on exercise capacity for systolic heart failure (HF); however, the effect on actual prognostic markers such as NTproBNP and minute ventilation/carbon dioxide production (VE/VCO2) slope has not been evaluated. The primary aim of the proposed study is to determine the effect of aerobic exercise training (AEX) on the VE/VCO2 slope and NTproBNP. The following databases (up to February 30, 2013) were searched with no language limitations: CENTRAL (The Cochrane Library 2013, issue 2), MEDLINE (from January 1966), EMBASE (from January 1980), and Physiotherapy Evidence Database (PEDro) (from January 1929). We screened reference lists of articles and also conducted an extensive hand search of the literature. Randomized controlled trials of exercise-based interventions with 2-month follow-up or longer compared to usual medical care or placebo were included. The study population comprised adults aged between 18 and 65 years, with evidence of chronic systolic heart failure (LVEF < 45 % and baseline NTproBNP > 300 pg/ml). Two review authors independently extracted data on study design, participants, interventions, and outcomes. We assessed the risk of bias using PEDro scale. We calculated mean differences (MD) or standardized mean differences between intervention and control groups for outcomes with sufficient data; for other outcomes, we described findings from individual studies. Eight studies involving a total of 408 participants met the inclusion criteria across the NTproBNP (5 studies with 191 patients) and VE/VCO2 slope (4 studies with 217 patients). Aerobic exercise significantly improved NTproBNP by a MD of -817.75 [95 % confidence interval (CI) -929.31 to -706.19]. Mean differences across VE/VCO2 slope were -6.55 (95 % CI -7.24 to -5.87). Those patients' characteristics and exercise were similar (frequency = 3-5 times/week; duration = 20-50 min/day; intensity = 60-80 % of VO2 peak) on the included studies. Moreover, the risk of bias across all studies was homogeneous (PEDro scale = 7-8 points). However, based on the statistical analysis, the heterogeneity among the studies was still high, which is related to the variable characteristics of the studies. Aerobic exercise may be effective at improving NTproBNP and the VE/VCO2 slope in systolic HF patients, but these effects are limited to a specific HF population meeting specific inclusion criterion in a limited number of studies. Future randomized controlled studies including diastolic and HF overleap with pulmonary diseases are needed to better understand the exact influence of AEX.

Noninvasive ventilation improves the cardiovascular response and fatigability during resistance exercise in patients with heart failure.

PURPOSE: Noninvasive ventilation may improve cardiovascular function and exercise performance. We evaluated the physiologic impact of noninvasive ventilation during isokinetic knee extension resistance exercise in patients with heart failure. METHODS: This clinical trial included 10 male compensated patients with ischemic heart failure (age, 57 ± 9.1 years; ejection fraction, 28.5 ± 5.8%). Subjects underwent 2 bouts of exercise on an isokinetic dynamometer, separated by 72 hours of rest. The resistance exercise was concentric knee extension, at a speed of 60°/s. Five sets of 10 repetitions were performed during the 2 exercise bouts, and each set was separated by 2 minutes of rest. Subjects were administered either bilevel positive airway pressure ventilation (BV) or sham ventilation 20 minutes before and during the 2 exercise sessions in a randomized fashion. Heart rate, systolic blood pressure, and diastolic blood pressure were measured at rest, during exercise, and into recovery. Changes in peak torque (ΔPT), total work (ΔTW), and power (ΔPw) between the fifth and first sets were also measured. RESULTS: Compared with the sham intervention, BV significantly decreased heart rate, systolic blood pressure, and diastolic blood pressure at rest and during exercise (P < .01). There were no significant differences in these variables during recovery. Bi-level positive airway pressure ventilation also significantly reduced ΔPT, ΔTW, and ΔPw compared with the sham intervention (P < .01). CONCLUSIONS: Bi-level positive airway pressure ventilation significantly improved the cardiovascular response and fatigability during resistance exercise in patients with heart failure. These results suggest that use of BV during exercise training may be beneficial in this population with chronic disease.