Exercise training in heart failure with reduced ejection fraction and permanent atrial fibrillation: A randomized clinical trial.

BACKGROUND: Heart failure (HF) associated with atrial fibrillation increases patients' physical inactivity, worsening their clinical condition and mortality. Exercise training is safe and has clear benefits in HF. However, little is known about the effects of exercise training on patients with HF with reduced ejection fraction and permanent atrial fibrillation (HFAF). OBJECTIVE: The purpose of this study was to test the hypothesis that exercise training improves functional capacity, cardiac function, and quality of life in patients with HFAF. METHODS: This randomized clinical trial was conducted at the Heart Institute. Patients with HFAF, left ventricular ejection fraction ≤40%, and resting heart rate (HR) ≤80 beats/min were included in the study. Cardiopulmonary testing, echocardiography, nervous system, and quality of life assessment were performed before and after the 12-week protocol period. RESULTS: Twenty-six patients (mean age 58 ± 1 years) were randomized to exercise training (HFAF-trained group; n = 13) or no training (HFAF-untrained group; n = 13). At baseline, no differences between the groups were found. Exercise improved peak oxygen consumption, slope of ventilation per minute/carbon dioxide production, and quality of life. The HFAF-trained group had significantly decreased resting HR (from 73 ± 2 to 69 ± 2 beats/min; P = .02) and recovery HR (from 148 ± 11 to 128 ± 9 beats/min; P = .001). Concomitantly, left ventricular ejection fraction increased (from 31% ± 1% to 36% ± 0.9%; P = .01), left atrial dimension decreased (from 52 ± 1.2 to 47 ± 1 mm; P = .03), and left ventricular end-systolic volume and left ventricular end-diastolic volume deceased (from 69 ± 2 to 64 ± 1.8 mL/m2 and from 99 ± 2.1 to 91 ± 2 mL/m2, respectively; P < .05). No changes were observed in the HFAF-untrained group. CONCLUSION: Exercise training can improve exercise capacity, quality of life, and cardiac function in patients with HF with reduced ejection fraction and permanent atrial fibrillation.

Nicotinamide attenuates streptozotocin-induced diabetes complications and increases survival rate in rats: role of autonomic nervous system.

BACKGROUND: To evaluate the effect of nicotinamide prior to streptozotocin-induced (STZ) diabetes in baroreflex sensitivity and cardiovascular autonomic modulation, and its association with hemodynamics and metabolic parameters. METHODS: Methods: Male Wistar rats were divided into control (Cont) and STZ-induced diabetes (Diab). Half of the rats from each group received a single dose of nicotinamide (100 mg/Kg) before STZ injection (Cont+NicA and Diab+NicA). All groups were followed-up for 5 weeks. RESULTS: Body weight loss of more than 40% was observed in Diab throughout the period (Diab: 271.00 ± 12.74 g; Diab+NicA: 344.62 ± 17.82). Increased glycemia was seen in Diab rats (541.28 ± 18.68 mg/dl) while Diab+NicA group had a slight decrease (440.87 ± 20.96 mg/dl). However, insulin resistance was observed only in Diab. In relation to Cont, heart rate, mean blood pressure and diastolic function were reduced when compared to Diab, together with parasympathetic modulation and baroreflex sensitivity. All of these parameters were improved in Diab+NicA when compared to Diab. Improved baroreflex sensitivity and parasympathetic modulation were correlated with glycemia, insulin resistance, and body weight mass. Additionally, Diab+NicA group increased survival rate. CONCLUSIONS: Results suggest that the association of nicotinamide in STZ-induced diabetic rats prevents most of the expected derangements mainly by preserving parasympathetic and baroreflex parameters.

Left ventricular basal region involvement in noncompaction cardiomyopathy.

A previously healthy 16-year-old woman experienced progressive dyspnea on exertion. The echocardiogram and cardiac magnetic resonance imaging showed a significant increase in cardiac chambers, severe biventricular systolic dysfunction, and prominent ventricular trabeculations suggesting noncompaction cardiomyopathy (NCC). The patient underwent heart transplantation 5 years after the NCC diagnosis, and the anatomopathological examination evidenced diffuse biventricular hypertrabeculation compromise, including the basal region of the biventricular wall. There is no consensus about the gold-standard diagnostic criteria, which demands a conceptual review and attention to another point: the relation of trabeculation volume and prognosis.