Heart Failure-Induced Diaphragm Myopathy

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Aerobic Exercise Training Prevents Heart Failure-Induced Skeletal Muscle Atrophy by Anti-Catabolic, but Not Anabolic Actions

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of age on aerobic capacity in heart failure patients under beta-blocker therapy: Possible impact in clinical decision-making?

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of N-acetylcysteine on oxidative stress in slow-twitch soleus muscle of heart failure rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Long-term low intensity physical exercise attenuates heart failure development in aging spontaneously hypertensive rats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Aerobic training attenuates nicotinic acetylcholine receptor changes in the diaphragm muscle during heart failure

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Growth hormone influences atrophy pathways in skeletal muscle of heart failure rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Exercise training and MAPK protein expression in rats with heart failure

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Exercise training decreases myocardial collagen III and heart failure signs rate, and improves physical performance in spontaneously hypertensive rats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Myosin heavy chain expression and atrophy in rat skeletal muscle during transition from cardiac hypertrophy to heart failure

The purpose of this investigation was to determine whether changes in myosin heavy chain (MHC) expression and atrophy in rat skeletal muscle are observed during transition from cardiac hypertrophy to chronic heart failure (CHF) induced by aortic stenosis (AS). AS and control animals were studied 12 and 18 weeks after surgery and when overt CHF had developed in AS animals, 28 weeks after the surgery. The following parameters were studied in the soleus muscle: muscle atrophy index (soleus weight/body weight), muscle fibre diameter and frequency and MHC expression. AS animals presented decreases in both MHC1 and type I fibres and increases in both MHC2a and type IIa fibres during late cardiac hypertrophy and CHF. Type IIa fibre atrophy occurred during CHF. In conclusion, our data demonstrate that skeletal muscle phenotype changes occur in both late cardiac hypertrophy and heart failure; this suggests that attention should be given to the fact that skeletal muscle phenotype changes occur prior to overt heart failure symptoms.

Regulation of cardiac microRNAs induced by aerobic exercise training during heart failure

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Hemodynamic response in one session of strength exercise with and without electrostimulation in heart failure patients: a randomized controlled trial

Background: Studies have investigated the influence of neuromuscular electrostimulation on the exercise/muscle capacity of patients with heart failure (HF), but the hemodynamic overload has never been investigated. The aim of our study was to evaluate the heart rate (HR), systolic and diastolic blood pressures in one session of strength exercises with and without neuromuscular electrostimulation (quadriceps) in HF patients and in healthy subjects. Methods: Ten (50% male) HF patients and healthy subjects performed three sets of eight repetitions with and without neuromuscular electrostimulation randomly, with one week between sessions. Throughout, electromyography was performed to guarantee the electrostimulation was effective. The hemodynamic variables were measured at rest, again immediately after the end of each set of exercises, and during the recovery period. Results: Systolic and diastolic blood pressures did not change during each set of exercises among either the HF patients or the controls. Without electrostimulation: among the controls, the HR corresponding to the first (85 ± 13 bpm, p = 0.002), second (84 ± 10 bpm, p < 0.001), third (89 ± 17, p < 0.001) sets and recuperation (83 ± 16 bpm, p = 0.012) were different compared to the resting HR (77 bpm). Moreover, the recuperation was different to the third set (0.018). Among HF patients, the HR corresponding to the first (84 ± 9 bpm, p = 0.041) and third (84 ± 10 bpm, p = 0.036) sets were different compared to the resting HR (80 ± 7 bpm), but this increase of 4 bpm is clinically irrelevant to HF. With electrostimulation: among the controls, the HR corresponding to the third set (84 ± 9 bpm) was different compared to the resting HR (80 ± 7 bmp, p = 0.016). Among HF patients, there were no statistical differences between the sets. The procedure was well tolerated and no subjects reported muscle pain after 24 hours. Conclusions: One session of strength exercises with and without neuromuscular electrostimulation does not promote a hemodynamic overload in HF patients. (Cardiol J 2011; 18, 1: 39-46)

Aerobic training attenuates nicotinic acethylcholine receptor changes in the diaphragm muscle during heart failure

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Exhaled Acetone as a New Biomarker of Heart Failure Severity

Background: Heart failure (HF) is associated with poor prognosis, and the identification of biomarkers of its severity could help in its treatment. In a pilot study, we observed high levels of acetone in the exhaled breath of patients with HF. The present study was designed to evaluate exhaled acetone as a biomarker of HF diagnosis and HF severity. Methods: Of 235 patients with systolic dysfunction evaluated between May 2009 and September 2010, 89 patients (HF group) fulfilled inclusion criteria and were compared with sex- and age-matched healthy subjects (control group, n = 20). Patients with HF were grouped according to clinical stability (acute decompensated HF [ADHF], n = 59; chronic HF, n = 30) and submitted to exhaled breath collection. Identification of chemical species was done by gas chromatography-mass spectrometry and quantification by spectrophotometry. Patients with diabetes were excluded. Results: The concentration of exhaled breath acetone (EBA) was higher in the HF group (median, 3.7 mu g/L; interquartile range [IQR], 1.69-10.45 mu g/L) than in the control group (median, 0.39 mu g/L; IQR, 0.30-0.79 mu g/L; P < .001) and higher in the ADHF group (median, 7.8 mu g/L; IQR, 3.6-15.2 mu g/L) than in the chronic HF group (median, 1.22 mu g/L; IQR, 0.68-2.19 P < .001). The accuracy and sensitivity of this method in the diagnosis of HF and ADHF were about 85%, a value similar to that obtained with B-type natriuretic peptide (BNP). EBA levels differed significantly as a function of severity of HF (New York Heart Association classification, P < .001). There was a positive correlation between EBA and BNP (r = 0.772, P < .001). Conclusions: EBA not only is a promising noninvasive diagnostic method of HF with an accuracy equivalent to BNP but also a new biomarker of HF severity. CHEST 2012; 142(2):457-466