Heart Failure Training Research Articles

Soluble ST2 in Ambulatory Patients With Heart Failure

Background— ST2 is involved in cardioprotective signaling in the myocardium and has been identified as a potentially promising biomarker in heart failure (HF). We evaluated ST2 levels and their association with functional capacity and long-term clinical outcomes in a cohort of ambulatory patients with HF enrolled in the Heart Failure: A Controlled Trial Investigating Outcomes of Exercise Training (HF-ACTION) study—a multicenter, randomized study of exercise training in HF. Methods and Results— HF-ACTION randomized 2331 patients with left ventricular ejection fraction <0.35 and New York Heart Association class II to IV HF to either exercise training or usual care. ST2 was analyzed in a subset of 910 patients with evaluable plasma samples. Correlations and Cox models were used to assess the relationship among ST2, functional capacity, and long-term outcomes. The median baseline ST2 level was 23.7 ng/mL (interquartile range, 18.6–31.8). ST2 was modestly associated with measures of functional capacity. In univariable analysis, ST2 was significantly associated with death or hospitalization (hazard ratio, 1.48; P <0.0001), cardiovascular death or HF hospitalization (hazard ratio, 2.14; P <0.0001), and all-cause mortality (hazard ratio, 2.33; P <0.0001; all hazard ratios for log 2 ng/mL). In multivariable models, ST2 remained independently associated with outcomes after adjustment for clinical variables and amino-terminal pro-B-type natriuretic peptide. However, ST2 did not add significantly to reclassification of risk as assessed by changes in the C statistic, net reclassification improvement, and integrated discrimination improvement. Conclusions— ST2 was modestly associated with functional capacity and was significantly associated with outcomes in a well-treated cohort of ambulatory patients with HF although it did not significantly affect reclassification of risk. Clinical Trial Information— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00047437.

Körperliches Training bei Herzinsuffizienz

In patients with chronic but stable heart failure (HF) exercise training is a recommended and widely accepted adjunct to an evidence-based management involving pharmacological and non-pharmacological therapies. Various pathophysiological mechanisms, such as central hemodynamics, vasculature, ventilation, skeletal muscle function as well as neurohormonal activation and inflammation are responsible for exercise intolerance described in HF patients. There is sufficient and growing evidence that exercise training in HF with reduced (HFrEF) and with preserved ejection fraction (HFpEF) is effective in improving exercise capacity, HF symptoms and quality of life. The positive effects of exercise training in HF are mediated by an improvement of central hemodynamics, endothelial function, inflammatory markers, neurohumoral activation, as well as skeletal muscle structure and function. In contrast to convincing data from a large meta-analysis, the large HF-ACTION study (Heart Failure-A Controlled Trial Investigating Outcomes of exercise TraiNing) only demonstrated a modest improvement of all cause mortality and hospitalizations in HFrEF. Outcome data in HFpEF are lacking. Whether interval training incorporating variable and higher intensities or the addition of resistance exercise to a standard aerobic prescription is superior in improving clinical status of HF patients is currently being examined. Despite increasing validation of the potential of exercise training in chronic HF, challenges remain in the routine therapeutic application, including interdisciplinary management, financing of long-term exercise programs and the need to improve short-term and long-term adherence to exercise training.

Effects of home versus hospital-based exercise training in chronic heart failure

Many researchers have demonstrated that supervised hospital-based training yields improvements in exercise capacity and quality of life (QoL) for heart failure (HF) sufferers [ 1 Davies E.J. Moxham T. Rees K. et al. Exercise Based Rehabilitation for Heart Failure (Review). in: Cochrane Database of Systematic Reviews. John Wiley, Chichester2010 Google Scholar ]. Though comparatively under-researched, home-training does not involve a potentially tiring return journey to hospital, and can be undertaken whenever the individual feels best able to exercise, therefore may offer a more pragmatic exercise option for this frail group [ 2 Chien C. Lee C. Wu Y. Chen T. Wu Y. Home-based exercise increases exercise capacity but not quality of life in people with chronic heart failure: a systematic review. Aust J Physiother. 2008; 54: 87-93 Google Scholar , 3 Hwang R. Marwick T. Efficacy of home-based exercise programmes for people with chronic heart failure: a meta-analysis. Eur J Cardiovasc Prev Rehabil. 2009; 16: 527-535 Google Scholar ]. Three previous non-controlled trials have compared effects of home and hospital-based exercise training in HF [ 4 Daskapan A. Arikan H. Caglar N. Tunali N. Ataman S. Comparison of supervised exercise training and home-based exercise training in chronic heart failure. Saudi Med J. 2005; 26: 842-847 Google Scholar , 5 Karapolat H. Demir E. Bozkaya Y.T. et al. Comparison of hospital-based versus home-based exercise training in patients with heart failure: effects on functional capacity, quality of life, psychological symptoms, and hemodynamic parameters. Clin Res Cardiol. 2009; 98: 635-642 Google Scholar , 6 Piotrowicz E. Baranowski R. Bilinska M. et al. A new model of home-based telemonitored cardiac rehabilitation in patients with heart failure: effectiveness, quality of life and adherence. Eur J Heart Fail. 2010; 12: 164-171 Google Scholar ]. Two [ 5 Karapolat H. Demir E. Bozkaya Y.T. et al. Comparison of hospital-based versus home-based exercise training in patients with heart failure: effects on functional capacity, quality of life, psychological symptoms, and hemodynamic parameters. Clin Res Cardiol. 2009; 98: 635-642 Google Scholar , 6 Piotrowicz E. Baranowski R. Bilinska M. et al. A new model of home-based telemonitored cardiac rehabilitation in patients with heart failure: effectiveness, quality of life and adherence. Eur J Heart Fail. 2010; 12: 164-171 Google Scholar ] found significant improvements in exercise capacity and QoL of up to 10% with both types of training, whilst the other [ 4 Daskapan A. Arikan H. Caglar N. Tunali N. Ataman S. Comparison of supervised exercise training and home-based exercise training in chronic heart failure. Saudi Med J. 2005; 26: 842-847 Google Scholar ] found that only hospital-training significantly improved exercise capacity (by 19%). To date, this is the only trial to compare effects of home versus hospital-based aerobic exercise training versus control upon exercise capacity and QoL in HF.

Abstract 180: The Effectiveness of a HF Training Program among Primary Care Physicians

Background: Heart failure (HF) guidelines recommend beta-blockers (BB) to reduce morbidity and mortality. BB doses are often suboptimal, which do not provide maximum benefit for HF patients. Differences in BB management patterns may exist between family practice (FP) and internal medicine (IM) physicians due to differences in specialty interest and training. Objectives: 1) To determine the effectiveness of a one-day training intervention for primary care physicians (PCPs) designed to optimize BB titration for patients with systolic HF. 2) To compare BB titration rates of FP and IM physicians. We hypothesized the intervention would result in increased PCP BB titration rates for experimental patients, with a more significant benefit in the FP group. Methods: A prospective cohort study was conducted at a county hospital with low-income, underserved HF patients (mean age 54.1±13.1, males 70%, mean ejection fraction 28.2±9.8, mean serum creatinine 1.5±1.0) for up to 7 clinic visits. Twelve participating PCPs, including 5 FP and 7 IM physicians, received a one-day training intervention on HF management with a focus on BB titration. Medical records of control patients who received care 2 years prior to the intervention (n=54) were compared to experimental patients after the intervention (n=81). A linear mixed model examined differences in BB dose between the experimental and control groups and the FP and IM physicians. Results: No sociodemographic or clinical differences were noted between HF patients treated before or after the intervention or between IM and FP physicians (p>0.05). The test of the group by time interaction showed no difference between the experimental and control groups in linear change trajectories for BB dose change (t= -0.12, p=0.91). However, FP physicians showed a significant change in BB titration rates for experimental patients (p=0.04) when compared to IM physicians. Conclusions: There was no difference in BB titration rates between the experimental and control groups following a HF training intervention for PCPs, although the clinical reasons for restricting maximal dosage were not explored. Teaching interventions targeting FP physicians may benefit HF patients in achieving higher BB doses and should be examined further.

Exercise training suppresses central command‐evoked sympathoexcitation in rats with heart failure

Sympathoexcitation evoked by central command, a parallel activation of the locomotor and autonomic neural circuits in the brain, has been shown to become exaggerated in heart failure (HF). In the present study, we tested whether exercise training (ET) in HF normalizes central command‐evoked sympathoexcitation. HF was induced in rats > 6 wks after coronary artery ligation. A subset of the HF rats was treadmill trained (20 m/min, 5% grade, 60 min/day, 5 days/wk, 8–14 wks) (HF+ET). Central command was activated by fictive locomotion in decerebrate rats. Fictive locomotion induced by 30‐s electrical stimulation at 35 μA of the mesencephalic locomotor region evoked a larger (P<0.05) increase in renal sympathetic nerve activity in HF rats [269 ± 45 arbitrary unit (AU), fractional shortening (FS) = 20 ± 3%, N12] than that in HF+ET (121 ± 33 AU, FS = 20 ± 2%, N10) and sham (111 ± 37 AU, FS=46 ± 3%, N6) rats. The sympathoexcitation in the HF rats was significantly reduced by bilateral injection into the rostral ventrolateral medulla of Tempol (10 mM, 100 nl), a superoxide dismutase mimetic. In the HF+ET and sham rats, Tempol had no effect on the response. These results suggest that ET has a therapeutic effect to suppress sympathoexcitation evoked by central command in HF. Further, the role played by central superoxide in amplifying central command‐evoked sympathoexcitation in HF may be altered by ET. Supported by JSPS Kaken 22790226 (SK).

The effect of a heart failure training intervention assessed via clinical simulation

Prehospital differential diagnosis of heart failure (HF) by paramedics is sometimes unreliable ( Schaider et al, 1995 ) and may lead to therapeutic interventions being withheld ( Jenkinson et al, 2008 ) or the initiation of inappropriate and potentially harmful treatment ( Wuerz and Meador, 1992 ). To date, no studies have evaluated the effect of participation in a HF training intervention on diagnostic accuracy among undergraduate UK paramedics assessed through clinical simulation. In this study, 17 paramedics were exposed to three mannequin based scenarios designed to simulate HF, pneumonia and chronic obstructive pulmonary disease (COPD). Participants were given up to 10 minutes to examine each mannequin and scrutinize clinical data before recording a diagnosis. Participant demographics and self reported confidence relating to assessment and management of HF were collected via a questionnaire. Two weeks later, participants attended a 90 minute targeted HF training intervention. Two weeks post training, the paramedics repeated the clinical simulation exercise and questionnaire. Initial diagnostic sensitivity and specificity for HF were higher than that reported in a previous UK clinical study, and improved following participation in a training intervention, although this failed to reach significance (83% vs 100% and 91.67 vs 100%, P>0.05). A significant improvement in self reported confidence relating to use of ECG findings in assessment of HF patients was noted (z=-2.309, P=0.021). In this study, paramedic differential diagnosis of HF assessed through clinical simulation demonstrated a non-significant trend towards improved sensitivity and specificity following participation in a targeted training intervention.

012 Does the introduction of a targeted heart failure training intervention improve diagnostic accuracy amongst undergraduate paramedics assessed through medical simulation?

BackgroundPrehospital diagnosis of Heart Failure (HF) by paramedics is sometimes unreliable and may lead to therapeutic interventions being unintentionally withheld, or the initiation of inappropriate and potentially harmful treatment. To...

Relationship of Doppler-Echocardiographic left ventricular diastolic function to exercise performance in systolic heart failure: The HF-ACTION study

Patients with systolic heart failure often have concomitant left ventricular (LV) diastolic dysfunction. Although in animal models diastolic dysfunction is associated with worsening exercise capacity and prognosis, information regarding these relationships in patients with established systolic heart failure (HF) is sparse. HF-ACTION was a large, multicenter National Institutes of Health-funded trial of exercise training in systolic HF (LV ejection fraction [LVEF] < or = 35%) and included detailed Doppler-echocardiographic (echo) and cardiopulmonary exercise testing at baseline. We tested the hypothesis that echo measures of LV diastolic function predict key cardiopulmonary exercise outcomes, including aerobic exercise capacity (peak exercise oxygen consumption, VO(2)), distance in the 6-minute walk test (6MWD), and ventilatory efficiency (VE/VCO(2) slope) in patients with systolic HF. Overall, 2,331 patients (28% women, median age 59 years, median LVEF 25%) were enrolled. There were significant bivariate correlations between echo diastolic function variables and peak VO(2) (inverse) and VE/VCO(2) slope (direct) that were strongest for ratio of early diastolic peak transmitral (MV) to myocardial tissue velocity (E/E'), peak MV early-to-late diastolic velocity ratio (E/A), and left atrial dimension (range of absolute r = 0.16-0.28). Both MV E/A and E/E' were more strongly related to all 3 exercise variables than was LVEF. The relationships of E/A and E/E' with 6MWD were weaker than with peak VO(2) or VE/VCO(2) slope. A multivariable model with peak VO(2) as the dependent variable, which included MV E/A and 9 demographic predictors including age, sex, race, body mass index, and New York Heart Association class, explained 40% of the variation in peak VO(2), with MV E/A explaining 6% of the variation. Including LVEF in the model explained less than an additional 1% of the variance in peak VO(2). In a multivariable model for VE/VCO(2) slope, MV E/A was the strongest independent echo predictor, explaining 10% of the variance. The relationship of LV diastolic function variables with 6MWD was weaker than with peak VO(2) or VE/VCO(2) slope. In patients with systolic HF, LV early diastolic function is a modest independent predictor of aerobic exercise capacity and appears to be a better predictor than LVEF.

Exercise training reduces sympathetic nerve activity in heart failure patients treated with carvedilol

Evidence suggests that carvedilol decreases muscle sympathetic nerve activity (MSNA) in patients with heart failure (HF) but carvedilol fails to improve forearm vascular resistance and overall functional capacity. Exercise training in HF reduces MSNA and improves forearm vascular resistance and functional capacity. To investigate whether the beneficial effects exercise training on MSNA are maintained in the presence of carvedilol. Twenty seven HF patients, NYHA Class II-III, EF <35%, peak VO(2) <20 ml/kg/min, treated with carvedilol were randomly divided into two groups: exercise training (n=15) and untrained (n=12). MSNA was recorded by microneurography. Forearm blood flow (FBF) was measured by venous occlusion plethysmography. The four-month training program consisted of three 60-min exercise/week on a cycloergometer. Baseline parameters were similar between groups. Exercise training reduced MSNA (-14+/-3.3 bursts/100 HB, p=0.001) and increased forearm blood flow (0.6+/-0.1 mL/min/100 g, p<0.001) in HF patients on carvedilol. In addition, exercise training improved peak VO(2) in HF patients (20+/-6%, p=0.002). MSNA, FBF and peak VO(2) were unchanged in untrained HF patients on carvedilol. Exercise training reduces MSNA in heart failure patients treated with carvedilol. In addition, the beneficial effects of exercise training on muscle blood flow and functional capacity are still realized in patients on carvedilol.