Hypotensive Effect of Heated Water-based Exercise in Older Individuals with Hypertension.

Blood pressure (BP) and hemodynamic response to heated water-based (HEx) vs. land-based exercise (LEx) were assessed in 15 (6 men) older hypertensives (age 66.4±4.9 yr) under pharmacological treatment. Participants were randomly assigned to perform 30 min of moderate-intensity HEx (walking inside the pool), LEx (walking on a treadmill) and non-exercise control (CON) intervention. Resting BP, arterial stiffness, endothelial reactivity and heart rate variability (HRV) were measured before, immediately after, and 45 min after interventions. 24-h ambulatory BP monitoring was performed after interventions. Resting systolic (but not diastolic) BP reduced 9.9±3.1 mmHg (P<0.01) 45 min after HEx only. 24-h systolic and diastolic, daytime diastolic and nightime systolic BP were lower (P<0.05) after HEx than both LEx and CON. Daytime systolic BP was also lower (P<0.05) after HEx than CON. Nighttime diastolic was not different between interventions. HEx-induced ambulatory BP reduction ranged 4.5±1.3 mmHg (24-h diastolic BP) to 9.5±3.0 mmHg (nighttime systolic BP), and persisted for 18/11 h in systolic/diastolic BP, when compared with CON. No significant changes in arterial stiffness, endothelial reactivity and HRV were found during any intervention. These results suggest that HEx may have important implications for managing BP in older hypertensive under pharmacological treatment.

Neurohumoral and Endothelial Responses to Heated Water-Based Exercise in Resistant Hypertensive Patients.

BACKGROUND: The neurohumoral and endothelial responses to the blood pressure (BP) lowering effects of heated water-based exercise (HEx) in resistant hypertension (HT) patients remain undefined.Methods and Results:We investigated these in 44 true resistant HT patients (age 53.3±0.9 years, mean±SEM). They were randomized and allocated to 2 groups, 28 to a HEx training protocol, which consisted of callisthenic exercises and walking in a heated pool for 1 h, three times weekly for 12 weeks and 16 patients to a control group maintaining their habitual activities. Measurements made before and after 12 weeks of HEx included clinic and 24-h BP, plasma levels of nitric oxide, endothelin-1, aldosterone, renin, norepinephrine and epinephrine, as well as peak V̇O2, and endothelial function (reactive hyperemia). After 12 weeks of HEx patients showed a significant decrease in clinic and 24-h systolic and diastolic BPs. Concomitantly, nitric oxide increased significantly (from 25±8 to 75±24 µmol/L, P<0.01), while endothelin-1 (from 41±5 to 26±3 pg/mL), renin (from 35±4 to 3.4±1 ng/mL/h), and norepinephrine (from 720±54 to 306±35 pg/mL) decreased significantly (P<0.01). Plasma aldosterone also tended to decrease, although not significantly (from 101±9 to 76±4 pg/mL, P=NS). Peak V̇O2increased significantly after HEx (P<0.01), while endothelial function was unchanged. No significant change was detected in the control group. CONCLUSIONS: The BP-lowering effects of HEx in resistant HT patients were accompanied by a significant reduction in the marked neurohumoral activation characterizing this clinical condition.

MicroRNAs: new players in heart failure.

MicroRNAs (miRNAs) are a class of non-coding small RNAs representing one of the most exciting areas of modern medical science. miRNAs modulate a large and complex regulatory network of gene expression of the majority of the protein-coding genes. Currently, evidences suggest that miRNAs play a crucial role in the pathogenesis of heart failure. Some miRNAs as miR-1, miR-133 and miR-208a are highly expressed in the heart and strongly associated with the development of cardiac hypertrophy. Recent data indicate that these miRNAs as well as miR-206 change their expression quickly in response to physical activity. The differential regulation of miRNAs in response to exercise suggests a potential value of circulating miRNAs (c-miRNAs) as biomarkers of physiological mediators of the cardiovascular adaptation induced by exercise. Likewise, serum levels of c-miRNAs such as miR-423-5p have been evaluated as potential biomarkers in the diagnosis and prognosis of heart failure. On the other hand, the manipulation of miRNAs levels using techniques such as 'miR mimics' and 'antagomiRs' is becoming evident the enormous potential of miRNAs as promising therapeutic strategies in heart failure.

Age-related maximum heart rate among ischemic and nonischemic heart failure patients receiving ß-blockade therapy.

BACKGROUND: Equations to predict maximum heart rate (HR(max)) in heart failure (HF) patients receiving ß-adrenergic blocking (BB) agents do not consider the cause of HF. We determined equations to predict HR(max) 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 HR(max) 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 VO(2) 16.9 ± 4.7 and 16.9 ± 5.2 mL kg(-1) min(-1) (P = NS), and the HR(max) 130.8 ± 23.3 and 125.3 ± 25.3 beats/min (P = .051) in ischemic and nonischemic patients, respectively. We devised the equation HR(max) = 168 - 0.76 × age (R(2) = 0.095; P = .007) for ischemic HF patients, but there was no significant relationship between age and HR(max) in nonischemic HF patients (R(2) = 0.006; P = NS). CONCLUSIONS: Our study suggests that equations to estimate HR(max) should consider the cause of HF.

Effects of ß-blocker therapy on exercise oscillatory ventilation in reduced ejection fraction heart failure patients: A case series study.

BACKGROUND: 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. ß-blockers (ßb) are prescribed for most HF patients; however, their effect on EOV remains unclear. We evaluated the effect of ßb on EOV in HF patients with reduced ejection fraction (HFrEF). METHODS: Fifteen patients diagnosed with HF, ejection fraction < 45%, aged from 18 to 65 years, were included before starting ßb therapy. Patients underwent clinical evaluation, cardiopulmonary exercise testing, echocardiography, laboratory exams (norepinephrine levels, B type natriuretic peptide) at baseline and after ßb 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). RESULTS: 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 ßb therapy from 25.9 ± 2.5% to 33 ± 2.6%, P = 0.02; peak VO2 did not significantly change (21.8 ± 1.7 vs 24.7 ± 1.9, P = 0.4); VE/VCO2 slope changed from 32.1 ± 10.6-27.5 ± 9.1, P = 0.03. Before ßb 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). CONCLUSION: In patients with HF, medical therapy with ßb can reverse EOV. This may explain why these patients experience symptom improvement after ßb therapy.

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.

Contemporary review of exercise in heart transplant recipients.

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.

Effects of the exercise training on skeletal muscle oxygen consumption in heart failure patients with reduced ejection fraction.

AIMS: Skeletal muscle dysfunction is a systemic consequence of heart failure (HF) that correlates with functional capacity. However, the impairment within the skeletal muscle is not well established. We investigated the effect of exercise training on peripheral muscular performance and oxygenation in HF patients. METHODS AND RESULTS: HF patients with ejection fraction ≤40% were randomized 2:1 to exercise training or control for 12 weeks. Muscle tissue oxygen was measured noninvasively by near-infrared spectroscopy (NIRS) during rest and a symptom-limited cardiopulmonary exercise test (CPET) before and after intervention. Measurements included skeletal muscle oxygenated hemoglobin concentration, deoxygenated hemoglobin concentration, total hemoglobin concentration, VO2 peak, VE/VCO2 slope, and heart rate. Muscle sympathetic nerve activity by microneurography, and muscle blood flow by plethysmography were also assessed at rest pre and post 12 weeks. Twenty-four participants (47.5 ± 7.4 years, 58% men, 75% no ischemic) were allocated to exercise training (ET, n = 16) or control (CG, n = 8). At baseline, no differences between groups were found. Exercise improved VO2 peak, slope VE/VCO2, and heart rate. After the intervention, significant improvements at rest were seen in the ET group in muscle sympathetic nerve activity and muscle blood flow. Concomitantly, a significant decreased in Oxy-Hb (from 29.4 ± 20.4 to 15.7 ± 9.0 µmol, p = 0.01), Deoxi-Hb (from 16.3 ± 8.2 to 12.2 ± 6.0 µmol, p = 0.003) and HbT (from 45.7 ± 27.6 to 27.7 ± 13.4 µmol, p = 0.008) was detected at peak exercise after training. No changes were observed in the control group. CONCLUSION: Exercise training improves skeletal muscle function and functional capacity in HF patients with reduced ejection fraction. This improvement was associated with increased oxygenation of the peripheral muscles, increased muscle blood flow, and decreased sympathetic nerve activity.

Residual Impact of Concurrent, Resistance, and High-Intensity Interval Training on Fasting Measures of Glucose Metabolism in Women With Insulin Resistance.

We sought to assess the residual effects (post 72-h training cessation) on fasting plasma glucose (FPG) and fasting insulin (FI) after 12-weeks of high-intensity interval training (HIIT), resistance training (RT), or concurrent training (CT) in women with insulin resistance (IR). We also aimed to determine the training-induced, post-training residual impact of CT. A total of adult 45 women (age 38.5±9.2years) were included in the final analysis and were assigned to a control (CG; n=13, BMI 28.3±3.6kg/m2), HIIT [n=14, BMI 28.6±3.6kg/m2, three sessions/wk., 80-100% of the maximum heart rate (HRmax)], RT [n=8, BMI 29.4±5.5kg/m2, two sessions/wk., 8-10 points of the modified Borg, corresponding to 20 to 50% range of one maximum repetition test (1RM)], or CT group (n=10, BMI 29.1±3.0kg/m2, three sessions/wk., 80-100% of HRmax, and 8-10 Borg, or 20 to 50% range of 1RM, to each HIIT and RT compounds), with the latter including both HIIT and RT regimens. Training interventions lasted 12-weeks. The main outcomes were FPG and FI measured at pre- and 24-h and 72-h post-training (FPG24h, FI24h, and FPG72h, FI72h, respectively). Secondary endpoints were body composition/anthropometry and the adiposity markers waist circumference (WC) and tricípital skinfold (TSF). The residual effects 72-h post-training [delta (∆)] were significantly poorer (all p<0.01) in the CT group (∆FPG72h+6.6mg/dl, η 2: 0.76) than in the HIIT (∆FPG72h+1.2mg/dl, η 2: 0.07) and RT (∆FPG72h+1.0mg/dl, η 2: 0.05) groups. These findings reveal that HIIT reduces FPG and RT reduces FI 24-h post-training; both exercise interventions alone have remarkably better residual effects on FPG and FI (post-72h) than CT in women with insulin resistance.

Atrial fibrillation in heart failure with reduced ejection fraction: a case report of exercise training.

BACKGROUND: Heart failure (HF) and atrial fibrillation (AF) are often concomitant and act in a vicious cycle. Atrial fibrillation is associated with greater functional limitations and increased morbidity and mortality in patients with HF. Moreover, AF associated with HF increases patients' physical inactivity, worsening their clinical condition, and prognosis. Exercise training is safe and has clear benefits in HF. However, these benefits have not been demonstrated when AF is associated with HF. CASE SUMMARY: We present the case of a 57-year-old man with permanent AF and HF with reduced ejection fraction, who underwent 12 weeks of exercise training that included cardiopulmonary exercise testing, neuromuscular sympathetic activity (NMSA), and muscle blood flow (MBF) before and after training. DISCUSSION: Exercise training was shown to have a potential benefit in reducing the activity of the sympathetic nerve and increasing muscle blood flow, as well as increasing VO2peak and decreasing the VE/VCO2 slope in a patient with AF associated with HF with reduced ejection fraction. These results may indicate favourable clinical implications in this group of patients.

High-Intensity Interval Versus Moderate-Intensity Continuous Training in Individuals With Parkinson's Disease: Hemodynamic and Functional Adaptation.

PURPOSE: To investigate the effect of high-intensity interval training (HIIT) versus moderate-intensity continuous exercise training (MICE) on hemodynamic and functional variables in individuals with Parkinson's disease. METHODS: Twenty participants (13 men) were randomly assigned to a thrice-weekly HIIT (n = 12) or MICE (n = 8) for 12 weeks. Hemodynamic (resting heart rate and blood pressure, carotid femoral pulse wave velocity, endothelial reactivity, and heart rate variability) and functional variables (5-time sit-to-stand, timed up and go, and 6-min walking tests) assessed before and after training. RESULTS: Demographic, hemodynamic and functional variables were similar between groups at baseline. Endothelial reactivity tended to increase after HIIT, but not after MICE, resulting in improved level (∼8%, P < .01) of this variable in HIIT versus MICE during follow-up. Six-minute walking test improved after HIIT (10.4 ± 3.8%, P < .05), but did not change after MICE. Sit to stand improved similarly after HIIT (27.2 ± 6.1%, P < .05) and MICE (21.5 ± 5.4%, P < .05). No significant changes were found after HIIT or MICE in any other variable assessed. CONCLUSION: These results suggest that exercise intensity may influence training-induced adaptation on endothelial reactivity and aerobic capacity in individuals with Parkinson's disease.

The Borg scale as an important tool of self-monitoring and self-regulation of exercise prescription in heart failure patients during hydrotherapy. A randomized blinded controlled trial.

BACKGROUND: The Borg Scale may be a useful tool for heart failure patients to self-monitor and self-regulate exercise on land or in water (hydrotherapy) by maintaining the heart rate (HR) between the anaerobic threshold and respiratory compensation point. METHODS AND RESULTS: Patients performed a cardiopulmonary exercise test to determine their anaerobic threshold/respiratory compensation points. The percentage of the mean HR during the exercise session in relation to the anaerobic threshold HR (%EHR-AT), in relation to the respiratory compensation point (%EHR-RCP), in relation to the peak HR by the exercise test (%EHR-Peak) and in relation to the maximum predicted HR (%EHR-Predicted) was calculated. Next, patients were randomized into the land or water exercise group. One blinded investigator instructed the patients in each group to exercise at a level between "relatively easy and slightly tiring". The mean HR throughout the 30-min exercise session was recorded. The %EHR-AT and %EHR-predicted did not differ between the land and water exercise groups, but they differed in the %EHR-RCP (95 +/-7 to 86 +/-7, P<0.001) and in the %EHR-Peak (85 +/-8 to 78 +/-9, P=0.007). CONCLUSIONS: Exercise guided by the Borg scale maintains the patient's HR between the anaerobic threshold and respiratory compensation point (ie, in the exercise training zone).

Prescribing high-intensity interval exercise by RPE in individuals with type 2 diabetes: metabolic and hemodynamic responses.

We tested the hypothesis that rating of perceived exertion (RPE) is a tool as efficient as the heart rate (HR) response to the cardiopulmonary exercise test (CPX) for prescribing and self-regulating high-intensity interval exercise (HIIE), and that metabolic and hemodynamic response to HIIE is superior than to continuous moderate-intensity exercise (MICE) in individuals with type 2 diabetes mellitus (T2DM). Eleven participants (age = 52.3 ± 3 years) underwent HIIE prescribed and self-regulated by RPE (HIIERPE; 25 min), HIIE prescribed and regulated by an individual's HR response to CPX (HIIEHR; 25 min), MICE prescribed and self-regulated by RPE (30 min) and control (30 min of seated resting) intervention in random order. HR, blood pressure (BP), capillary glucose, endothelial reactivity, and carotid-femoral pulse wave velocity were assessed before, immediately after, and 45 min after each intervention. Exercise HR, speed, and distance were measured during exercise sessions. Twenty-four-hour ambulatory BP was measured after each intervention. Exercise HR, speed, and distance were similar between HIIERPE and HIIEHR. BP response was not different among HIIERPE, HIIEHR, and MICE. Capillary glycaemia reduction was greater (P < 0.05) after HIIERPE (48.6 ± 9.6 mg/dL) and HIIEHR (47.2 ± 9.5 mg/dL) than MICE (29.5 ± 11.5 mg/dL). Reduction (P < 0.05) in 24-h (6.7 ± 2.2 mm Hg) and tendency toward reduction (P = 0.06) in daytime systolic (7.0 ± 2.5 mm Hg) ambulatory BP were found only after HIIERPE. These results suggest that HIIE is superior to MICE for reducing glycaemia and ambulatory BP, and that the 6-20 RPE scale is a useful tool for prescribing and self-regulating HIIE in individuals with T2DM.

Prognostic value of cardiopulmonary exercise testing in children with heart failure secondary to idiopathic dilated cardiomyopathy in a non-beta-blocker therapy setting.

BACKGROUND: Peak oxygen consumption and resting left ventricular ejection fraction (LVEF) are independent predictors of survival in adult heart failure (HF) patients. AIM: To evaluate these factors in children. METHODS: We prospectively studied 31 children with NYHA class I to III HF (mean LVEF 26+/-10%; mean age 8.6+/-1.9 years). All had dilated cardiomyopathy and were awaiting heart transplantation. A cardiopulmonary treadmill exercise test was performed and LVEF determined by radionuclide ventriculography. RESULTS: During a median follow-up of 1282 days, 20 children reached at least one end-point (death or heart transplantation). Clinical data from the 11 children without events and the 20 children with events are as follows: NYHA class 1+/-0 vs. 2+/-0.9 (p<0.01); SBP 118+/-17 vs. 102+/-16 (p=0.01); DBP 70+/-10 vs. 61+/-10 (p=0.02); heart rate 165+/-22 vs. 148+/-22 (NS); double-product 19+/-4 vs. 15+/-4 (p=0.01); end-tidal carbon dioxide tension (PetCO2) 35+/-5 vs. 30+/-6 (NS); oxygen consumption (VO2) 22+/-5.4 vs. 18.3+/-5.7 (NS); exercise time 19+/-4 vs. 13+/-6 (p<0.003), and LVEF 31+/-8 vs. 22+/-10 (p=0.02). These variables all correlated with prognosis on univariate analysis. In multivariate analysis, only decreasing exercise time and LVEF were predictive of events during follow-up (p<0.001 and 0.04). CONCLUSION: These findings suggest that reduction in LVEF and exercise tolerance in children with heart failure is predictive of functional status.

Reproducibility of the self-controlled six-minute walking test in heart failure patients.

INTRODUCTION: 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. PURPOSE: To test the reproducibility of the six-minute treadmill cardiopulmonary walk test (6CWT) using the Borg scale and to make sure that all patients undergo a submaximal test. METHODS: Twenty-three male heart failure patients (50+/-9 years) were included; these patients had both ischemic (5) and non-ischemic (18) heart failure with a left ventricle ejection fraction of 23+/-7%, were diagnosed as functional class NYHA II-III and were undergoing optimized drug therapy. Patients were guided to walk at a pace between "relatively easy and slightly tiring" (11 and 13 on Borg scale). The 6CWT using the Borg scale was performed two times on a treadmill with zero inclination and patient control of speed with an interval of 24 hours. During the sixth minute, we analyzed ventilation (VE, L/min), respiratory quotient, Oxygen consumption (VO2, ml/kg/min), VE/VCO2 slope, heart rate (HR, bpm), systolic blood pressure (SBP, mmHg), diastolic (DBP, mmHg) blood pressure and distance. RESULTS: The intraclass correlation coefficients at the sixth minute were: HR (r i=0.96, p<0.0001), VE (r i=0.84, p<0.0001), SBP (r i=0.72, p=0.001), distance (r i=0.88, p<0.0001), VO2 (r i=0.92, p<0.0001), SlopeVE/VCO2 (r i=0.86, p<0.0001) and RQ<1 (r i=0.6, p=0.004). CONCLUSION: Using the 6CWT with the Borg scale was reproducible, and it seems to be an appropriate method to evaluate the functional capacity of heart failure patients while making sure that they undergo a submaximal walking test.

Heart rate dynamics during a treadmill cardiopulmonary exercise test in optimized beta-blocked heart failure patients.

BACKGROUND: 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. AIM: The aim of this study was to evaluate heart rate dynamics (basal, peak and % heart rate increase) in optimized beta-blocked heart failure patients compared to sedentary, normal individuals (controls) during a treadmill cardiopulmonary exercise test. METHODS: Twenty-five heart failure patients (49+/-11 years, 76% male), with an average LVEF of 30+/-7%, and fourteen controls were included in the study. Patients with atrial fibrillation, a pacemaker or noncardiovascular functional limitations or whose drug therapy was not optimized were excluded. Optimization was considered to be 50 mg/day or more of carvedilol, with a basal heart rate between 50 to 60 bpm that was maintained for 3 months. RESULTS: Basal heart rate was lower in heart failure patients (57+/-3 bpm) compared to controls (89+/-14 bpm; p<0.0001). Similarly, the peak heart rate (% maximum predicted for age) was lower in HF patients (65.4+/-11.1%) compared to controls (98.6+/-2.2; p<0.0001). Maximum respiratory exchange ratio did not differ between the groups (1.2+/-0.5 for controls and 1.15+/-1 for heart failure patients; p=0.42). All controls reached the maximum heart rate for their age, while no patients in the heart failure group reached the maximum. Moreover, the % increase of heart rate from rest to peak exercise between heart failure (48+/-9%) and control (53+/-8%) was not different (p=0.157). CONCLUSION: No patient in the heart failure group reached the maximum heart rate for their age during a treadmill cardiopulmonary exercise test, despite the fact that the percentage increase of heart rate was similar to sedentary normal subjects. A heart rate increase in optimized beta-blocked heart failure patients during cardiopulmonary exercise test over 65% of the maximum age-adjusted value should be considered an effort near the maximum. This information may be useful in rehabilitation programs and ischemic tests, although further studies are required.

Safety profile and efficacy of ivabradine in heart failure due to Chagas heart disease: a post hoc analysis of the SHIFT trial.

AIMS: The SHIFT trial showed that ivabradine reduced heart rate (HR) and the risk of cardiovascular outcomes. Concerns remain over the efficacy and safety of ivabradine on heart failure (HF) due to Chagas disease (ChD). We therefore conducted a post hoc analysis of the SHIFT trial to investigate the effect of ivabradine in these patients. METHODS AND RESULTS: SHIFT was a randomized, double-blind, placebo-controlled trial in symptomatic systolic stable HF, HR ≥ 70 b.p.m., and in sinus rhythm. The ChD HF subgroup included 38 patients, 20 on ivabradine, and 18 on placebo. The ChD HF subgroup showed high prevalence of bundle branch right block and, compared with the overall SHIFT population, lower systolic blood pressure; higher use of diuretics, cardiac glycosides, and antialdosterone agents; and lower use of angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker or target daily dose of beta-blocker. ChD HF presented a poor prognosis (all-cause mortality at 2 years was ~60%). The mean twice-daily dose of ivabradine was 6.26 ± 1.15 mg and placebo 6.43 ± 1.55 mg. Ivabradine reduced HR from 77.9 ± 3.8 to 62.3 ± 10.1 b.p.m. (P = 0.005) and improved functional class (P = 0.02). A trend towards reduction in all-cause death was observed in ivabradine arm vs. placebo (P = 0.07). Ivabradine was not associated with serious bradycardia, atrioventricular block, hypotension, or syncope. CONCLUSIONS: ChD HF is an advanced form of HF with poor prognosis. Ivabradine was effective in reducing HR in these patients and improving functional class. Although our results are based on a very limited sample and should be interpreted with caution, they suggest that ivabradine may have a favourable benefit-risk profile in ChD HF patients.

High-Intensity Interval Training in Heart Transplant Recipients: A Systematic Review with Meta-Analysis.

Heart transplantation (HTx) is considered an efficient and gold-standard procedure for patients with end-stage heart failure. After surgery, patients have lower aerobic power (VO2max) and compensatory hemodynamic responses. The aim of the present study was to assess through a systematic review with meta-analysis whether high-intensity interval training (HIIT) can provide benefits for those parameters. This is a systematic review with meta-analysis, which searched the databases and data portals PubMed, Web of Science, Scopus, Science Direct and Wiley until December 2016 (pairs). The following terms and descriptors were used: "heart recipient" OR "heart transplant recipient" OR "heart transplant" OR "cardiac transplant" OR "heart graft". Descriptors via DeCS and Mesh were: "heart transplantation'' OR "cardiac transplantation". The words used in combination (AND) were: "exercise training" OR "interval training" OR "high intensity interval training" OR "high intensity training" OR "anaerobic training" OR "intermittent training" OR "sprint training". The initial search identified 1064 studies. Then, only those studies assessing the influence of HIIT on the post-HTx period were added, resulting in three studies analyzed. The significance level adopted was 0.05. Heart transplant recipients showed significant improvement in VO2peak, heart rate and peak blood pressure in 8 to 12 weeks of intervention.

Hypotensive Effect of Heated Water-Based Exercise Persists After 12-Week Cessation of Training in Patients With Resistant Hypertension.

BACKGROUND: Heated water-based exercise (HEx) promotes a marked reduction of blood pressure (BP), but it is not entirely clear whether its effects on BP persist after cessation of HEx. METHODS: We analyzed the effects of cessation of HEx on 24-hour ambulatory BP monitoring (ABPM) in patients with resistant hypertension (RH). Thirty-two patients (aged 53 ± 6 years) with RH (4 to 6 antihypertensive drugs) were randomly assigned to HEx (n = 16) or control (n = 16) groups. Antihypertensive therapy remained unchanged during the protocol. The HEx group participated in 36 sessions (60 minutes) in a heated pool (32oC [89.6°F]) for 12 weeks (training), followed by 12 weeks of cessation of training. The control group was evaluated during the same period and instructed to maintain their habitual activities. RESULTS: HEx and control groups had similar BP levels at baseline. HEx training reduced the 24-hour systolic (-19.5 ± 4.6 vs 3.0 ± 0.7 mm Hg, P = 0.001) and diastolic BP (-11.1 ± 2.4 vs 2.06 ± 0.9 mm Hg, P = 0.001) at week 12, compared with the control group. After 12 weeks of training cessation (week 24), 24-hour BP remained significantly lower in the HEx group than in the control group (-9.6 ± 3.8 vs 6.3 ± 3.5 mm Hg, P = 0.01 and -7.5±2.2 vs 2.2 ± 1.0 mm Hg, P = 0.009, for systolic and diastolic BP, respectively), although these differences were attenuated. CONCLUSIONS: BP remained lower after cessation of 12-week training among patients with RH who underwent HEx compared with the controls. The carryover effects of HEx on BP may help to overcome the challenging problem of exercise compliance in long-term follow-up.