Effects of noninvasive ventilation with bilevel positive airway pressure on exercise tolerance and dyspnea in heart failure patients.

BACKGROUND: Heart failure (HF) is a syndrome that results in inadequate blood supply, leading to a number of structural and functional changes. Noninvasive ventilatory support (NIVS) is used as an adjuvant treatment to improve the functional capacity of these patients. OBJECTIVE: To investigate the effect of NIVS with bilevel positive airway pressure ventilation (BiPAP) on exercise tolerance and dyspnea in HF patients. METHODS: Forty patients with New York Heart Association class I/II/III HF were randomly assigned either to a NIVS group (n = 20) or control group (n = 20). All patients underwent two 6-min walk tests (6MWT), with a 30-min interval between them. In the NIVS group, the patients performed the BiPAP with an inspiratory positive airway pressure of 12 cmH2O and expiratory positive airway pressure of 6 cmH2O for 30 min. At baseline, and after the first and second 6MWT, the heart rate, systolic and diastolic blood pressure, peripheral oxygen saturation (SaO2), and dyspnea were evaluated. RESULTS: Forty patients completed the study safely according to the randomization protocol, and no adverse events were reported during the tests. The NIVS group showed a significant improvement in the 6MWT distance (68.3 vs. 9.8 m) and dyspnea (1.3 vs. 3.1) compared with the control group. No serious adverse events were reported. CONCLUSIONS: NIVS/BiPAP showed beneficial effects on exercise tolerance and dyspnea. It was safe and well tolerated by HF patients and should be considered for inclusion in cardiac rehabilitation programs.

Addition of non-invasive ventilatory support to combined aerobic and resistance training improves dyspnea and quality of life in heart failure patients: a randomized controlled trial.

OBJECTIVE: To test the hypothesis that combined aerobic and resistance training and non-invasive ventilatory support result in additional benefits compared with combined aerobic and resistance training alone in heart failure patients. DESIGN: A randomized, single-blind, controlled study. SETTING: Cardiac rehabilitation center. PARTICIPANTS: A total of 46 patients with New York Heart Association class II/III heart failure were randomly assigned to a 10-week program of combined aerobic and resistance training, plus non-invasive ventilatory support ( n = 23) or combined aerobic and resistance training alone ( n = 23). METHODS: Before and after intervention, results for the following were obtained: 6-minute walk test, forced vital capacity, forced expiratory volume at one second, maximal inspiratory muscle pressure, and maximal expiratory muscle pressure, with evaluation of dyspnea by the London Chest Activity of Daily Living scale, and quality of life with the Minnesota Living With Heart Failure questionnaire. RESULTS: Of the 46 included patients, 40 completed the protocol. The combined aerobic and resistance training plus non-invasive ventilatory support, as compared with combined aerobic and resistance training alone, resulted in significantly greater benefit for dyspnea (mean change: 4.8 vs. 1.3, p = 0.004), and quality of life (mean change: 19.3 vs. 6.8, p = 0.017 ). In both groups, the 6-minute walk test improved significantly (mean change: 45.7 vs. 44.1, p = 0.924), but without a statistically significant difference. CONCLUSION: Non-invasive ventilatory support combined with combined aerobic and resistance training provides additional benefits for dyspnea and quality of life in moderate heart failure patients. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02384798. Registered 03 April 2015.

Aspectos histológicos da epífise de crescimento ósseo em resposta ao exercício físico extenuante em camundongos / Histologic aspects of bone growth epiphysis after strenuous physical exercise in mice

Procurou-se identificar se existe alteração histológica na epífise de crescimento ósseo de camundongos submetidos a exercício físico extenuante. Para tanto, foi realizada uma pesquisa experimental com uma amostra de 8 camundongos, que ficaram em condições ambientes em um biotério, alimentados com água e ração comum, ad libitum. A ninhada foi dividida em dois grupos, um grupo controle e um grupo experimental, sendo que, o grupo experimental foi submetido a um exercício físico extenuante, caracterizado pelo aumento do nível de ácido láctico sanguíneo, realizado por 40 minutos/dia, durante 20 dias ininterruptos. Ao final da intervenção, foram confeccionadas lâminas histológicas, com cortes longitudinais do fêmur dos camundongos e analisadas em um microscópio óptico. Os dados obtidos mostraram alteração na estrutura epifisária do grupo experimental com aparente diminuição da zona proliferativa do disco epifisário, articulação mais desenvolvida e aumento das espículas ósseas com diminuição das trabéculas, sugerindo uma maturação precoce da epífise de crescimento. Através da análise dos resultados, conclui-se que o exercício físico extenuante modifica a estrutura da epífise de crescimento ósseo em camundongos.

The aim of this study was to identify histological alterations in bone growth epiphysis of mice submitted to a tiring physical exercise. For so, it was carried out an experimental research with a sample of 8 mice that stayed in environment conditions, fed with water and common feed, ad libitum. The brood was divided in two groups, a control group and an experimental group, being the experimental group submitted to a tiring physical exercise, characterized by the increasing of blood lactate level, carried out by 40 minutes/day, during 20 days uninterrupted. At the end of the intervention, were confectioned histological slides corresponding to the bone growth epiphysis of the femur of the mice and analyzed in an light microscope. Data showed an alteration in the epiphysis structure in the experimental group, with apparent decrease of the proliferation zone of epiphysis disc, an articulation more evolution and an increase of bone specula’s with a decrease of trabeculaes, what suggests an early maturation, accelerating the substitution of cartilaginous woven by bone weave. Through the analysis of the results, it was concluded that the tiring physical exercise modifies the structure of bone growth epiphysis in mice.