Comprehensive analysis of cardiopulmonary exercise testing and mortality in patients with systolic heart failure: the Henry Ford Hospital cardiopulmonary exercise testing (FIT-CPX) project

Physical Fitness Is Directly Related to Exercise Capacity and Ventilatory Response to Exercise in Men with HFrEF

Background: Heart failure (HF) patients experience reduced functional fitness level (determining the performance of routine, daily activities) and diminished exercise capacity (linked to more effortful activities). Aim: The aim of the study is to assess this relationship using functional fitness tests compared to peak VO2 and VE/VCO2 slope in the context of exercise capacity and ventilatory response to exercise. Methods: A total of 382 men with stable HFrEF (age: 61 ± 10, NYHA class I/II/III/IV: 16/50/32/2%, LVEF: 30.5 ± 8.3%) underwent cardiopulmonary exercise testing (CPX) and a Senior Fitness Test (SFT). Afterwards, the patients were divided according to the 2capacity with peak VO2 ≥ 18 mL/kg/min, those with higher or lower ventilatory responses (VE/VCO2 slope ≥ 35 vs. <35) to the exercise were compared. Results: Patients who covered shorter distances in the 6 min walking test showed worse results in the functional tests ('stand up and go', 'chair stand' and 'arm curl') and CPX (lower peak VO2, shorter exercise time and higher VE/VCO2 slope). Subjects classified into Class D demonstrated the worst results in all elements of SFT; those in Class A demonstrated the best results. Significant differences that were analogous occurred also between classes B and C. Among the participants who reached peak VO2 ≥ 18 mL/kg/min (n = 170), those with VE/VCO2 slope ≥ 35 were characterized by worse physical fitness as compared to those with VE/VCO2 < 35. Conclusion: Reduced exercise tolerance led to worsening physical function in patients with HFrEF. Moreover, limitations in physical fitness seem to be distinctive for those patients showing excessive ventilatory response to exercise slope VE/VCO2 (≥35). The Senior Fitness Test may be considered as a useful tool for assessing comprehensive functional and clinical status and risk stratification in patients with HFrEF, especially those with extremely low exercise capacity.

Clinical and functional effects of beta-blocker therapy discontinuation in patients with biventricular heart failure

BACKGROUND

Nearly two-thirds of patients with heart failure with reduced ejection fraction (HFrEF) have right ventricular dysfunction, previously identified as an independent predictor of reduced functional capacity and poor prognosis. Beta-blocker therapy (β-BT) reduces mortality and hospitalizations in patients with HFrEF and is approved as first-line therapy regardless of concomitant right ventricular function. However, the exact role of sympathetic nervous system activation in right ventricular dysfunction and the potential usefulness (or harmfulness) of β-BT in these patients are still unclear.

OBJECTIVES

The aim of the study is to evaluate the medium-term effect of β-BT discontinuation on functional capacity and right ventricular remodelling based on cardiopulmonary exercise testing (CPET), echocardiography and serum biomarkers in patients with clinically stable biventricular dysfunction.

METHODS

In this single-centre, open-label, prospective trial, 16 patients were enrolled using the following criteria: patients were clinically stable without signs of peripheral congestion; NYHA II-III while on optimal medical therapy (including β-BT); LVEF 40% or less; echocardiographic criteria of right ventricular dysfunction. Patients were randomized 1 : 1 either to withdraw (group 0) or continue (group 1) β-BT. In group 0, optimal heart rate was obtained with alternative rate-control drugs. Echo and serum biomarkers were performed at baseline, after 3 and 6 months; CPET was performed at baseline and 6 months. Mann--Whitney U test was adopted to determine the relationships between β-BT discontinuation and effects on right ventricular dysfunction.

RESULTS

At 6 months' follow up, S' DTI improved (ΔS': 1.01 vs. -0.92 cm/s; P = 0.03), while estimated PAPs (ΔPAPs: 0.8 vs. -7.5 mmHg; P = 0.04) and echo left ventricular-remodelling (ΔEDVi: 19.55 vs. -0.96 ml/mq; P = 0.03) worsened in group 0. In absolute terms, the only variables significantly affected by β-BT withdrawal were left ventricular EDV and ESV, appearing worse in group 0 (mean EDVi 115 vs. 84 ml/mq; mean ESVi 79 vs. 53.9 ml/mq, P = 0.03). No significant changes in terms of functional capacity were observed after β-BT withdrawal.

CONCLUSION

In HFrEF patients with concomitant right ventricular dysfunction, β-BT discontinuation did not produce any beneficial effects. In addition, despite maintenance of optimal heart rate control, β-BT discontinuation induced worsening of left ventricular remodelling. Our study corroborates the hypothesis that improvement in left ventricular function may likewise be a major determinant for improvement in right ventricular function, reducing pulmonary wedge pressure and right ventricular afterload, with only a marginal action of its negative inotropic effect. In conclusion, β-BT appears beneficial also in heart failure patients with biventricular dysfunction.

Cardiopulmonary exercise testing criteria for advanced therapies in patients with heart failure

Many cardiology associations endorse the role of the cardiopulmonary exercise test (CPET) to define the severity of impairment of functional capacity in individuals with heart failure with reduced ejection fraction (HFrEF) and when evaluating the need for advanced therapies for these patients. The focus of the CPET within the cardiology community has been on peak volume of oxygen uptake (VO2). However, several CPET variables are associated with outcomes in individuals with and without chronic disease and can inform clinical decisions in individuals with HFrEF. In this manuscript, we will review the normal cardiopulmonary response to a graded exercise test and review current guideline recommendations relative to CPET in patients with HFrEF.

2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure" replaces the "2013 ACCF/AHA Guideline for the Management of Heart Failure" and the "2017 ACC/AHA/HFSA Focused Update of the 2013 ACCF/AHA Guideline for the Management of Heart Failure." The 2022 guideline is intended to provide patient-centric recommendations for clinicians to prevent, diagnose, and manage patients with heart failure.

METHODS

A comprehensive literature search was conducted from May 2020 to December 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (PubMed), EMBASE, the Cochrane Collaboration, the Agency for Healthcare Research and Quality, and other relevant databases. Additional relevant clinical trials and research studies, published through September 2021, were also considered. This guideline was harmonized with other American Heart Association/American College of Cardiology guidelines published through December 2021. Structure: Heart failure remains a leading cause of morbidity and mortality globally. The 2022 heart failure guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with heart failure, with the intent to improve quality of care and align with patients' interests. Many recommendations from the earlier heart failure guidelines have been updated with new evidence, and new recommendations have been created when supported by published data. Value statements are provided for certain treatments with high-quality published economic analyses.

2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure

AIM

The "2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure" replaces the "2013 ACCF/AHA Guideline for the Management of Heart Failure" and the "2017 ACC/AHA/HFSA Focused Update of the 2013 ACCF/AHA Guideline for the Management of Heart Failure." The 2022 guideline is intended to provide patient-centric recommendations for clinicians to prevent, diagnose, and manage patients with heart failure.

METHODS

A comprehensive literature search was conducted from May 2020 to December 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (PubMed), EMBASE, the Cochrane Collaboration, the Agency for Healthcare Research and Quality, and other relevant databases. Additional relevant clinical trials and research studies, published through September 2021, were also considered. This guideline was harmonized with other American Heart Association/American College of Cardiology guidelines published through December 2021.

STRUCTURE

Heart failure remains a leading cause of morbidity and mortality globally. The 2022 heart failure guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with heart failure, with the intent to improve quality of care and align with patients' interests. Many recommendations from the earlier heart failure guidelines have been updated with new evidence, and new recommendations have been created when supported by published data. Value statements are provided for certain treatments with high-quality published economic analyses.

Low Walking Impairment Questionnaire score after a recent myocardial infarction identifies patients with polyvascular disease

Objectives

To evaluate whether the Walking Impairment Questionnaire score could identify patients with polyvascular disease in a population with recent myocardial infarction and their association with cardiovascular events during two-year follow-up.

Design

A prospective observational study.

Setting

Patients admitted to the acute coronary care unit, the Department of Cardiology, Uppsala University Hospital.

Participants

Patients admitted with acute Non-STEMI- or STEMI-elevation myocardial infarction.

Main outcome measures

The Walking Impairment Questionnaire, developed as a self-administered instrument to assess walking distance, speed, and stair climbing in patients with peripheral artery disease, predicts future cardiovascular events and mortality. Two hundred and sixty-three patients with recent myocardial infarction answered Walking Impairment Questionnaire. Polyvascular disease was defined as abnormal findings in the coronary- and carotid arteries and an abnormal ankle–brachial index. The calculated score for each of all three categories were divided into quartiles with the lowest score in first quartile.

Results

The lowest (worst) quartile in all three Walking Impairment Questionnaire categories was associated with polyvascular disease, fully adjusted; distance, odds ratio (OR) 5.4 (95% confidence interval (CI) 1.8–16.1); speed, OR 7.4 (95% CI 1.5–36.5); stair climbing, OR 8.4 (95% CI 1.0–73.6). In stair climbing score, patients with the lowest (worst) score had a higher risk for the composite cardiovascular endpoint compared to the highest (best) score; hazard ratio 5.3 (95% CI 1.5–19.0). The adherence to medical treatment was high (between 81.7% and 99.2%).

Conclusions

The Walking Impairment Questionnaire is a simple tool to identify myocardial infarction patients with more widespread atherosclerotic disease and although well treated medically, stair climbing predicts cardiovascular events.

Exercise Oscillatory Ventilation: Interreviewer Agreement and a Novel Determination

INTRODUCTION

Determination of exercise oscillatory ventilation (EOV) is subjective, and the interreviewer agreement has not been reported. The purposes of this study were, among patients with heart failure (HF), as follows: 1) to determine the interreviewer agreement for EOV and 2) to describe a novel, objective, and quantifiable measure of EOV.

METHODS

This was a secondary analysis of the HEART Camp: Promoting Adherence to Exercise in Patients with Heart Failure study. EOV was determined through a blinded review by six individuals on the basis of their interpretation of the EOV literature. Interreviewer agreement was assessed using Fleiss kappa (κ). Final determination of EOV was based on agreement by four of the six reviewers. A new measure (ventilation dispersion index; VDI) was calculated for each test, and its ability to predict EOV was assessed with the receiver operator characteristics curve.

RESULTS

Among 243 patients with HF (age, 60 ± 12 yr; 45% women), the interreviewer agreement for EOV was fair (κ = 0.303) with 10-s discrete data averages and significantly better, but only moderate (κ = 0.429) with 30-s rolling data averages. Prevalence rates of positive and indeterminate EOVs were 18% and 30% with the 10-s discrete averages and 14% and 13% with the 30-s rolling averages, respectively. VDI was strongly associated with EOV, with areas under the receiver operator characteristics curve of 0.852 to 0.890.

CONCLUSIONS

Interreviewer agreement for EOV in patients with HF is fair to moderate, which can negatively affect risk stratification. VDI has strong predictive validity with EOV; as such, it might be a useful measure of prognosis in patients with HF.

Exercise Capacity and the Obesity Paradox in Heart Failure: The FIT (Henry Ford Exercise Testing) Project

OBJECTIVES

To assess the influence of exercise capacity and body mass index (BMI) on 10-year mortality in patients with heart failure (HF) and to synthesize these results with those of previous studies.

PATIENTS AND METHODS

This large biracial sample included 774 men and women (mean age, 60±13 years; 372 [48%] black) with a baseline diagnosis of HF from the Henry Ford Exercise Testing (FIT) Project. All patients completed a symptom-limited maximal treadmill stress test from January 1, 1991, through May 31, 2009. Patients were grouped by World Health Organization BMI categories for Kaplan-Meier survival analyses and stratified by exercise capacity (<4 and ≥4 metabolic equivalents [METs] of task). Associations of BMI and exercise capacity with all-cause mortality were assessed using multivariable-adjusted Cox proportional hazards models.

RESULTS

During a mean follow-up of 10.1±4.6 years, 380 patients (49%) died. Kaplan-Meier survival plots revealed a significant positive association between BMI category and survival for exercise capacity less than 4 METs (log-rank, P=.05), but not greater than or equal to 4 METs (P=.76). In the multivariable-adjusted models, exercise capacity (per 1 MET) was inversely associated, but BMI was not associated, with all-cause mortality (hazard ratio, 0.89; 95% CI, 0.85-0.94; P<.001 and hazard ratio, 0.99; 95% CI, 0.97-1.01; P=.16, respectively).

CONCLUSION

Maximal exercise capacity modified the relationship between BMI and long-term survival in patients with HF, upholding the presence of an exercise capacity-obesity paradox dichotomy as observed over the short-term in previous studies.

Cardiopulmonary Exercise Measures of Men and Women with HFrEF Differ in Their Relationship to Prognosis: The Henry Ford Hospital Cardiopulmonary Exercise Testing (FIT-CPX) Project

BACKGROUND

This study evaluated if different prognostic characteristics exist for peak oxygen consumption (VO₂), percent predicted peak VO₂ (ppVO₂), and the slope of the change in minute ventilation to volume of carbon dioxide produced (V_E-VCO₂) slope between men and women with heart failure and reduced ejection fraction (HFrEF).

METHODS

Analysis of the Henry Ford Hospital Cardiopulmonary Exercise Testing database (n = 1085; 33% women, 55% black) of individuals with HFrEF who completed a physician-referred cardiopulmonary exercise testing (CPX) between 1997 and 2010. Primary outcome was a composite of all-cause death, left ventricular assist device placement, and orthotopic heart transplant . Logistic and Cox regressions were performed and Kaplan-Meier survival curves were developed to describe relationships of the CPX variables and the composite outcome within and between men and women.

RESULTS

All patients were followed-up for a minimum of 5 years, during which there were 643 combined events (62%; 499 deaths, 64 left ventricular assist device implants, 80 orthotopic heart transplant). Each CPX variable was significantly related to event-free survival among both men and women. Log-rank assessment of Kaplan-Meier curves noted survival differences for peak VO₂ and V_E-VCO₂ slope (p ≤ .002), but not ppVO₂ (P = .32), between men and women.

CONCLUSIONS

Prognostic values for peak VO₂ and the V_E-VCO₂ slope might be considered separately for men and women, whereas the ppVO₂ value corresponding to 1- and 3-year survival rates may not be different between the sexes.

Relationship between the prognostic value of ventilatory efficiency and age in patients with heart failure

Background

Ventilatory efficiency decreases with age. This study aimed to investigate the prognostic significance and cut-off value of the minute ventilation/carbon dioxide production (VE/VCO2) slope according to age in patients with heart failure.

Methods and results

We analysed 1501 patients with heart failure from our observational cohort who performed maximal symptom-limited cardiopulmonary exercise testing and separated them into three age groups (≤55 years, 56–70 years and ≥71 years) in total and according to the three ejection fraction categories defined by European Society of Cardiology guidelines. The endpoint was set as heart failure events, hospitalisation for heart failure or death from heart failure. The VE/VCO2 slope increased with age. During the median follow-up period of 4 years, 141 heart failure (9%) events occurred. In total, univariate Cox analyses showed that the VE/VCO2 slope (cont.) was significantly related to heart failure events, while on multivariate analysis, the prognostic significance of the VE/VCO2 slope (cont.) was poor, accompanied by a significant interaction with age ( P < 0.0001). The cut-off value of the VE/VCO2 slope increased with the increase in age in not only the total but also the sub-ejection fraction categories. Multivariate analyses with a stepwise method adjusted for estimated glomerular filtration rate, peak oxygen consumption, atrial fibrillation and brain natriuretic peptide, showed that the predictive value of the binary VE/VCO2 slope separated by the cut-off value varied according to age. There was a tendency for the prognostic significance to increase with age irrespective of ejection fraction.

Conclusion

The prognostic significance and cut-off value of the VE/VCO2 slope may increase with advancing age.

Variables Measured During Cardiopulmonary Exercise Testing as Predictors of Mortality in Chronic Systolic Heart Failure

BACKGROUND

Data from a cardiopulmonary exercise (CPX) test are used to determine prognosis in patients with chronic heart failure (HF). However, few published studies have simultaneously compared the relative prognostic strength of multiple CPX variables.

OBJECTIVES

The study sought to describe the strength of the association among variables measured during a CPX test and all-cause mortality in patients with HF with reduced ejection fraction (HFrEF), including the influence of sex and patient effort, as measured by respiratory exchange ratio (RER).

METHODS

Among patients (n = 2,100, 29% women) enrolled in the HF-ACTION (HF-A Controlled Trial Investigating Outcomes of exercise traiNing) trial, 10 CPX test variables measured at baseline (e.g., peak oxygen uptake [Vo2], exercise duration, percent predicted peak Vo2 [%ppVo2], ventilatory efficiency) were examined.

RESULTS

Over a median follow-up of 32 months, there were 357 deaths. All CPX variables, except RER, were related to all-cause mortality (all p < 0.0001). Both %ppVo2 and exercise duration were equally able to predict (Wald chi-square: ∼141) and discriminate (c-index: 0.69) mortality. Peak Vo2 (ml·kg(-1)·min(-1)) was the strongest predictor of mortality among men (Wald chi-square: 129) and exercise duration among women (Wald chi-square: 41). Multivariable analyses showed that %ppVo2, exercise duration, and peak Vo2 (ml·kg(-1)·min(-1)) were similarly able to predict and discriminate mortality. In men, a 10% 1-year mortality rate corresponded to a peak Vo2 of 10.9 ml·kg(-1)·min(-1) versus 5.3 ml·kg(-1)·min(-1) in women.

CONCLUSIONS

Peak Vo2, exercise duration, and % ppVo2 carried the strongest ability to predict and discriminate the likelihood of death in patients with HFrEF. The prognosis associated with a given peak Vo2 differed by sex. (Exercise Training Program to Improve Clinical Outcomes in Individuals With Congestive Heart Failure; NCT00047437).