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Idiopathic dilated cardiomyopathy prognosis is influenced by endothelial dysfunction in adults with heart failure but this information is lacking in children.

Background:The origin of dyspnea in chronic heart failure (HF) is multifactorial, and excessive ventilation is thought to play a role in inducing this symptom. Chemosensivity is augmented in HF, correlates with increased pulmonary ventilation (VE), and is an adverse prognostic marker. Despite increased blood levels of natriuretic peptides in clinical conditions associated with dyspnea, their effect on pulmonary VE and chemoreceptor activity remains unexplored. Methods:We tested in a prospective, placebo‐controlled, three‐way cross‐over, double‐blind randomized study the effects of the recombinant form of the natural human B‐type natriuretic peptide (R‐BNP) in comparison with placebo and levosimendan on chemoreflex sensitivity at rest, as well as their effects on pulmonary VE, systemic blood pressure, heart rate and sympathetic serum activity both at rest and during exercise. Results:Eleven stable chronic HF patients were randomized to sessions of 6‐min treadmill‐walking tests during placebo, or levosimendan or R‐BNP intravenous infusion in the following conditions: room air, hypoxia, and hypercapnia. R‐BNP administration determined higher pulmonary ventilatory response at rest and during exercise (P< 0.001) consequent to a boost of respiratory rate (P< 0.001) under room air and hypoxia conditions. Norepinephrine blood levels increased from rest to exercise in all conditions without differences among placebo, levosimendan, and R‐BNP effects. BNP blood levels remained unchanged. Conclusions:The novelty of the present findings is that R‐BNP infusion in HF patients can boost pulmonary ventilatory response at rest and during exercise.

Background:Conventional cardiac rehabilitation program consist of 15 min of warm‐up, 30 min of aerobic exercise and followed by 15 min calisthenics exercise. The Pilates method has been increasingly applied for its therapeutic benefits, however little scientific evidence supports or rebukes its use as a treatment in patients with heart failure (HF). Purpose:Investigate the effects of Pilates on exercise capacity variables in HF. Methods:Sixteen pts with HF, left ventricular ejection fraction 27 ± 14%, NYHA class I–II were randomly assigned to conventional cardiac rehabilitation program (n = 8) or mat Pilates training (n = 8) for 16 weeks of 30 min of aerobic exercise followed by 20 min of the specific program. Results:At 16 weeks, pts in the mat Pilates group and conventional group showed significantly increase on exercise time 11.9 ± 2.5 to 17.8 ± 4 and 11.7 ± 3.9 to 14.2 ± 4 min, respectively. However, only the Pilates group increased significantly the ventilation (from 56 ± 20 to 69 ± 17 L/min, P= 0.02), peak VO2(from 20.9 ± 6 to 24.8 ± 6 mL/kg/min, P= 0.01), and O2pulse (from 11.9 ± 2 to 13.8 ± 3 mL/bpm, P= 0.003). The Pilates group showed significantly increase in peak VO2when compared with conventional group (24.8 ± 6 vs. 18.3 ± 4, P= 0.02). Conclusions:The result suggests that the Pilates method may be a beneficial adjunctive treatment that enhances functional capacity in patients with HF who are already receiving standard medical therapy.

Although it is known that obesity, diabetes, and Kawasaki's disease play important roles in systemic inflammation and in the development of both endothelial dysfunction and cardiomyopathy, there is a lack of data regarding the endothelial function of pre-pubertal children suffering from cardiomyopathy. In this study, we performed a systematic review of the literature on pre-pubertal children at risk of developing cardiomyopathy to assess the endothelial function of pre-pubertal children at risk of developing cardiomyopathy. We searched the published literature indexed in PubMed, Bireme and SciELO using the keywords 'endothelial’, 'children’, 'pediatric’ and 'infant’ and then compiled a systematic review. The end points were age, the pubertal stage, sex differences, the method used for the endothelial evaluation and the endothelial values themselves. No studies on children with cardiomyopathy were found. Only 11 papers were selected for our complete analysis, where these included reports on the flow-mediated percentage dilatation, the values of which were 9.80±1.80, 5.90±1.29, 4.50±0.70, and 7.10±1.27 for healthy, obese, diabetic and pre-pubertal children with Kawasaki's disease, respectively. There was no significant difference in the dilatation, independent of the endothelium, either among the groups or between the genders for both of the measurements in children; similar results have been found in adolescents and adults. The endothelial function in cardiomyopathic children remains unclear because of the lack of data; nevertheless, the known dysfunctions in children with obesity, type 1 diabetes and Kawasaki's disease may influence the severity of the cardiovascular symptoms, the prognosis, and the mortality rate. The results of this study encourage future research into the consequences of endothelial dysfunction in pre-pubertal children.

Background:Heart transplantation is a gold‐standard treatment for selected patients in the terminal stages of heart failure and it can improve patients' quality of life, exercise capacity, and survival. Despite of the exercise performance in heart transplant recipients increases with respect to pre‐transplantation, it still remains subnormal when compared with healthy subjects. Exercise training is an important nonpharmacological tool in heart transplant recipients to improve the exercise capacity, muscle strength, quality of life, and the chronotropic response. Despite this there is no consensus about what methods of aerobic exercise prescription are more adequate. Aim:The purpose of this review is to provide an up‐to‐date summary of the direct and indirect methods of prescription of aerobic exercise training in heart transplant recipients. Conclusion:The indirect methods of aerobic exercise prescription seem to be very frail and they do not seem to be reliable in heart transplant recipients.

We sought to evaluate the neurohormonal activity in heart transplant recipients and compare it with that in heart failure patients and healthy subjects during rest and just after a 6-minute walking test.

In recent years, beta‐blocker therapy has become a primary pharmacologic intervention in patients with heart failure by blocking the sympathetic activity. To compare the exercise training's sympathetic blockade in healthy subjects (athletes) and the carvedilol's sympathetic blockade in sedentary heart failure patients by the evaluation of the heart rate dynamic during an exercise test. A total of 26 optimized and 49 nonoptimized heart failure patients in a stable condition (for, at least, 3 months), 15 healthy athletes and 17 sedentary healthy subjects were recruited to perform a cardiopulmonary exercise test. The heart rate dynamic (rest, reserve, peak and the peak heart rate in relation to the maximum predicted for age) was analyzed and compared between the four groups. The heart rate reserve was the same between optimized (48 ± 15) and nonoptimized (49 ± 18) heart failure patients (P< 0.0001). The athletes (188 ± 9) showed a larger heart rate reserve compared to sedentary healthy subjects (92 ± 10, P< 0.0001). Athletes and healthy sedentary reached the maximum age‐predicted heart ratefor their age, but none of the heart failure patients did. The carvedilol's sympathetic blockade occurred during the rest and during the peak effort in the same proportion, but the exercise training's sympathetic blockade in healthy subjects occurred mainly in the rest.

In recent years, beta-blocker therapy has become a primary pharmacologic intervention in patients with heart failure by blocking the sympathetic activity. To compare the exercise training's sympathetic blockade in healthy subjects (athletes) and the carvedilol's sympathetic blockade in sedentary heart failure patients by the evaluation of the heart rate dynamic during an exercise test. A total of 26 optimized and 49 nonoptimized heart failure patients in a stable condition (for, at least, 3 months), 15 healthy athletes and 17 sedentary healthy subjects were recruited to perform a cardiopulmonary exercise test. The heart rate dynamic (rest, reserve, peak and the peak heart rate in relation to the maximum predicted for age) was analyzed and compared between the four groups. The heart rate reserve was the same between optimized (48 ± 15) and nonoptimized (49 ± 18) heart failure patients (P< 0.0001). The athletes (188 ± 9) showed a larger heart rate reserve compared to sedentary healthy subjects (92 ± 10, P< 0.0001). Athletes and healthy sedentary reached the maximum age-predicted heart ratefor their age, but none of the heart failure patients did. The carvedilol's sympathetic blockade occurred during the rest and during the peak effort in the same proportion, but the exercise training's sympathetic blockade in healthy subjects occurred mainly in the rest.

The relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients either on non-optimized or off beta-blocker therapy is known to be unreliable. The aim of this study was to evaluate the relationship between the percentage of oxygen consumption reserve and percentage of heart rate reserve in heart failure patients receiving optimized and non-optimized beta-blocker treatment during a treadmill cardiopulmonary exercise test.

Calculating the maximum heart rate for age is one method to characterize the maximum effort of an individual. Although this method is commonly used, little is known about heart rate dynamics in optimized beta-blocked heart failure patients.

The six-minute walk test (6WT) has been proposed to be a submaximal test, but could actually demand a high level of exercise intensity from the patient, expressed by a respiratory quotient >1.0, following the guideline recommendations. Standardizing the 6WT using the Borg scale was proposed to make sure that all patients undergo a submaximal walking test.

To determine and compare the cardiopulmonary responses of healthy children and children with heart failure due to idiopathic dilated cardiomyopathy (IC) to progressive treadmill exercise testing.