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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. [ABSTRACT FROM AUTHOR]

Abstract: Background: Equations to predict maximum heart rate (HRmax) in heart failure (HF) patients receiving β-adrenergic blocking (BB) agents do not consider the cause of HF. We determined equations to predict HRmax in patients with ischemic and nonischemic HF receiving BB therapy. Methods and Results: Using treadmill cardiopulmonary exercise testing, we studied HF patients receiving BB therapy being considered for transplantation from 1999 to 2010. Exclusions were pacemaker and/or implantable defibrillator, left ventricle ejection fraction (LVEF) >50%, peak respiratory exchange ratio (RER) <1.00, and Chagas disease. We used linear regression equations to predict HRmax based on age in ischemic and nonischemic patients. We analyzed 278 patients, aged 47 ± 10 years, with ischemic (n = 75) and nonischemic (n = 203) HF. LVEF was 30.8 ± 9.4% and 28.6 ± 8.2% (P = .04), peak VO2 16.9 ± 4.7 and 16.9 ± 5.2 mL kg−1 min−1 (P = NS), and the HRmax 130.8 ± 23.3 and 125.3 ± 25.3 beats/min (P = .051) in ischemic and nonischemic patients, respectively. We devised the equation HRmax = 168 − 0.76 × age (R 2 = 0.095; P = .007) for ischemic HF patients, but there was no significant relationship between age and HRmax in nonischemic HF patients (R 2 = 0.006; P = NS). Conclusions: Our study suggests that equations to estimate HRmax should consider the cause of HF. [Copyright &y& Elsevier]

Heart transplantation (HTx) is a therapeutic option for a selected group of patients with end-stage heart failure. Although secondary prevention including exercise therapy is recommended in the management of patients following HTx, little information is available on their metabolic and physiological consequences in HTx. Therefore, we aimed to conduct a contemporary review the effectiveness of exercise therapy on functional capacity, cardiovascular health and health-related quality of life for adult HTx patients. We searched the database MEDLINE for articles published between January 2015 and October 2020 and were able to include 6 studies involving 202 patients. Larger improvements in exercise capacity were seen after high-intensity interval training and in patients with evidence of cardiac reinnervation. Clinically relevant reductions were observed for daytime and 24 h ambulatory blood pressure after exercise training and following a single bout of aerobic exercise. Finally, limited data suggest that quality of life is higher in HTx patients following high-intensity training. In summary, the available evidence shows the potential for exercise as a vital treatment in patients following HTx. Yet, the scant data calls for more well-designed and adequately powered studies to support its effectiveness and to unravel optimal exercise characteristics, which would allow for more effective and person-tailored exercise prescription. • Exercise training is a safe and effective tool to promote favorable physiological adaptations. • Exercise intensity and cardiac reinnervation can modulate the improvement in cardiorespiratory fitness and blood pressure. • High intensity exercise training is associated with a higher quality of life. • There is no evidence about the effect of exercise intensity on the immune response. [ABSTRACT FROM AUTHOR]

Exercise oscillatory ventilation (EOV) is an abnormal breathing pattern that occurs in ~20% of patients with heart failure (HF) and is associated with poor prognosis and exercise intolerance. β-blockers (βb) are prescribed for most HF patients; however, their effect on EOV remains unclear. We evaluated the effect of βb on EOV in HF patients with reduced ejection fraction (HFrEF). Fifteen patients diagnosed with HF, ejection fraction < 45%, aged from 18 to 65 years, were included before starting βb therapy. Patients underwent clinical evaluation, cardiopulmonary exercise testing, echocardiography, laboratory exams (norepinephrine levels, B type natriuretic peptide) at baseline and after βb therapy optimized for six months. Presence of exercise oscillatory breathing was determined by two experienced observers who were blinded to the moment of the test (pre or post). Fifteen patients (1 female), aged 49.5 ± 2.5 years, with HFrEF, NYHA I-III enrolled in the study. The etiologies of the HFrEF were idiopathic (n = 8) and hypertensive (n = 7). LVEF increased after βb therapy from 25.9 ± 2.5% to 33 ± 2.6%, P = 0.02; peak VO 2 did not significantly change (21.8 ± 1.7 vs 24.7 ± 1.9, P = 0.4); VE/VCO 2 slope changed from 32.1 ± 10.6–27.5 ± 9.1, P = 0.03. Before βb initiation, nine patients (60%) had EOV, but only two (13%) did after optimized therapy. McNemar test was used to evaluate the significance of the association between the two moments (P = 0.02). In patients with HF, medical therapy with βb can reverse EOV. This may explain why these patients experience symptom improvement after βb therapy. [Display omitted] • The pattern of presentation and the clinical course of EOV suggest distinct pathophysiological mechanisms during sleep and exercise. • Carvedilol appears to play an important role in normalizing EOV. This effect is independent of the beneficial effects of digoxin, diuretics, and ACE inhibitors. • Patients with HF, especially those experiencing EOV, the maximum tolerated dose of carvedilol should be considered. • Heart failure patients with reduced ejection fraction may merit special attention in the presence of EOV. [ABSTRACT FROM AUTHOR]

Abstract: Background: Some trials suggest that the titration of Carvedilol is based on rest heart rate from 50 to 60 bpm and a target daily dose of 50 mg/day. Aim: To evaluate the heart rate dynamic in heart failure patients with different sensibilities of the Carvedilol therapy during an exercise test. Methods: Patients were divided into four groups and submitted a treadmill cardiopulmonary exercise test: heart rate >60 bpm and Carvedilol60 bpm and Carvedilol >=50 mg/day (19 patients) (non-optimized low-sensibility); heart rate between 50 and 60 bpm and Carvedilol >=50 mg/day (16 patients) (optimized); heart rate between 50 and 60 bpm and Carvedilol<50 mg/day (10 patients) (optimized high-sensible group). Results: The heart rate peak and the percentage of the peak heart rate in relation with the maximum heart rate predicted for age during the cardiopulmonary exercise test were the same between the non-optimized (128±13, bpm; 74±7%) and non-optimized low-sensibility (136±20, bpm; 78±8%) groups, and between the optimized (105±25, bpm; 60±13%) and optimized high-sensible (108±16, bpm; 62±8%) groups. The heart rate reserve was the same. Conclusion: The heart rate dynamic was almost the same between groups with rest heart rate >60 bpm and between groups <60 bpm, independently of the Carvedilol dose. Based on these findings, we propose a new method to titrate carvedilol therapy by the cardiopulmonary exercise test. [Copyright &y& Elsevier]

Abstract: Background: In healthy subjects, the percentage of heart rate reserve (%HRR) versus the percentage of oxygen consumption reserve (%VO2R) is the closest relationship between heart rate and VO2 and it seems also to be true to heart failure patients only if they are under optimized beta-blocker therapy. Aim: To evaluate the closest relationship between heart rate and VO2 (%peak heart rate versus %peak VO2; %HRR versus %VO2R or absolute heart rate versus absolute VO2) in heart transplant recipients during a treadmill cardiopulmonary exercise test. Methods: A total of 19 sedentary heart transplant recipients (5.4±3.3years after transplant) in a stable condition (for, at least, 3months), were recruited to perform a cardiopulmonary exercise test. The relationship between %HRR–%VO2R, %peak heart rate versus %peak VO2 and absolute heart rate versus absolute VO2 were tested. Results: The strongest relationship was found between %HRR–%VO2R (r =0.95, p <0.0001), followed by %peak heart rate versus %peak VO2 (r =0.91, p <0.0001) and absolute heart rate versus absolute VO2 (r =0.67, p <0.0001). The mean regression line did not coincide with the line of identity in any group (p <0.0001 for all groups). Conclusion: The %HRR versus %VO2R showed the closest relationship followed by %peak heart rate versus %peak VO2 and absolute heart rate versus absolute VO2. Despite this, the perfect reliability of the heart rate versus VO2 was not found. [ABSTRACT FROM AUTHOR]