Estimating maximum work rate during cardiopulmonary exercise testing from the six-minute walk distance in patients with heart failure.

Background: Exercise is recommended for patients with chronic heart failure (CHF) and its intensity is usually set as a percentage of the maximal work rate (MWR) during cardiopulmonary exercise testing (CPX) or a symptom-limited incremental test (SLIT). As these tests are not always available in cardiac rehabilitation due to logistic/cost constraints, we aimed to develop a predictive model to estimate MWR at CPX (estMWR@CPX) in CHF patients using anthropometric and clinical measures and the 6-min walk test (6 MWT), the most widely used exercise field test. Methods: This is a multicentre cross-sectional retrospective study in a cardiac rehabilitation setting. Six hundred patients with HF in New York Heart Association (NYHA) functional class I-III underwent both CPX and 6 MWT and, through multivariable linear regression analysis, we defined several predictive models to define estMWR@CPX. Results: The best model included 6 MWT, sex, age, weight, NYHA class, left ventricular ejection fraction (LVEF), smoking status and chronic obstructive pulmonary disease COPD (adjusted R2 = 0.55; 95% LoA -39 to 33 W). When LVEF was excluded as a predictor, the resulting model performed only slightly worse (adjusted R2 = 0.54; 95% LoA -42 to 34 W). Only in 34% of cases was the percentage difference between estMWR@CPX and real MWR@CPX <10% in absolute value. EstMWR@CPX tended to overestimate low values and underestimate high values of true MWR@CPX. Conclusions: Our results showed a lack of accuracy in the predictive model evaluated; therefore, for an accurate prescription of cycle-ergometer exercise training, it is necessary to assess MWR by CPX or SLIT.

Revisiting a Prognosticating Algorithm from Cardiopulmonary Exercise Testing in Chronic Heart Failure (from the MECKI Score Population).

Cardiopulmonary exercise testing is a prognostic tool in heart failure with reduced left ventricular ejection fraction (HFrEF). Prognosticating algorithms have been proposed, but none has been validated. In 2017, a predictive algorithm, based on peak oxygen consumption (VO2), ventilatory response to exercise (ventilation [VE] carbon dioxide production [VCO2], the VE/VCO2 slope), exertional oscillatory ventilation (EOV), and peak respiratory exchange ratio, was recommended, according treatment with ß blockers: patients with HFrEF registered in the metabolic exercise test data combined with cardiac and kidney indexes (MECKIs) database were used to validated this algorithm. According to the inclusion/exclusion criteria, 4,683 MECKI patients with HFrEF were enrolled. At 3 years follow-up, the end point was cardiovascular death and urgent heart transplantation (cardiovascular events [CV]). CV events occurred in 25% in patients without ß blockers, whereas those with ß-blockers had 11% (p <0.0001). In patients without ß blockers, 36%, 24%, and 7% CV events were observed in those with peak VO2 ≤10, with peak VO2 >10 <18, and with peak VO2 ≥18 ml/kg/min (p = 0.0001), respectively; in MECKI patients with peak VO2 ≤10 and patients with intermediate exercise capacity, a peak respiratory exchange ratio (≥1.15) and VE/VCO2 slope (≥35) were diriment, respectively (p = 0.0001). EOV, when occurred, increased risk. In MECKI patients on ß blockers, 29%, 17%, and 8% CV events were noticed in those with a peak VO2 ≤8, with peak VO2 = 8 to 12, and patients with peak VO2 ≥12 ml/kg/min, respectively (p = 0.0000); when EOV was monitored an increment of risk was witnessed. In conclusion, the outcome of this algorithm was confirmed with the MECKI cohort.

Pick Your Threshold: A Comparison Among Different Methods of Anaerobic Threshold Evaluation in Heart Failure Prognostic Assessment.

BACKGROUND: In clinical practice, anaerobic threshold (AT) is used to guide training and rehabilitation programs, to define risk of major thoracic or abdominal surgery, and to assess prognosis in heart failure (HF). AT of oxygen uptake (V.O2; V.O2AT) has been reported as an absolute value (V.O2ATabs), as a percentage of predicted peak V.O2 (V.O2AT%peak_pred), or as a percentage of observed peak V.O2 (V.O2AT%peak_obs). A direct comparison of the prognostic power among these different ways to report AT is missing. RESEARCH QUESTION: What is the prognostic power of these different ways to report AT? STUDY DESIGN AND METHODS: In this observational cohort study, we screened data of 7,746 patients with HF with a history of reduced ejection fraction (< 40%) recruited between 1998 and 2020 and enrolled in the Metabolic Exercise Combined With Cardiac and Kidney Indexes register. All patients underwent a maximum cardiopulmonary exercise test, executed using a ramp protocol on an electronically braked cycle ergometer. RESULTS: This study considered 6,157 patients with HF with identified AT. Follow-up was median, 4.2 years (25th-75th percentiles, 1.9-5.0 years). Both V.O2ATabs (mean ± SD, 823 ± 305 mL/min) and V.O2AT%peak_pred (mean ± SD, 39.6 ± 13.9%), but not V.O2AT%peak_obs (mean ± SD, 69.2 ± 17.7%), well stratified the population regarding prognosis (composite end point: cardiovascular death, urgent heart transplant, or left ventricular assist device). Comparing area under the receiver operating characteristic curve (AUC) values, V.O2ATabs (0.680) and V.O2AT%peak_pred (0.688) performed similarly, whereas V.O2AT%peak_obs (0.538) was significantly weaker (P < .001). Moreover, the V.O2AT%peak_pred AUC value was the only one performing as well as the AUC based on peak V.O2 (0.710), with an even a higher AUC (0.637 vs 0.618, respectively) in the group with severe HF (peak V.O2 < 12 mL/min/kg). Finally, the combination of V.O2AT%peak_pred with peak V.O2 and V. per CO2 production shows the highest prognostic power. INTERPRETATION: In HF, V.O2AT%peak_pred is the best way to report V.O2 at AT in relationship to prognosis, with a prognostic power comparable to that of peak V.O2 and, remarkably, in patients with severe HF.

Functional capacity assessment and Minimal Clinically Important Difference in post-acute cardiac patients: the role of Short Physical Performance Battery.

BACKGROUND: The Short Physical Performance Battery (SPPB) test is a well-established tool to assess physical performance, and to identify frail patients. Assessment of the SPPB in a specific population of elder patients in cardiac rehabilitation phase after a cardiac event is missing. AIM: The aim of this study was to correlate SPPB and the cardiac rehabilitation outcome in a group of elder patients after a cardiac event and to identify the Minimal Clinically Important Difference (MCID) of the SPPB. METHODS: Consecutive (n = 392) patients aged ≥75 years, in the rehabilitation phase after cardiac surgery (70.1%), congestive heart failure (7.4%), or acute coronary syndrome (22.5%), were enrolled. SPPB was performed twice: on admission and discharge. The MCID was assessed with the 'anchor method', and the Patient Global Impression of Change was employed as the anchor. RESULTS: On admission, SPPB classified 56, 117, 116, and 94 patients as severe, moderate, mild, or minimal/no limitations, respectively. Patients with the lower SPPB had the longer length of stay, and the higher complications rate. At receiver operating characteristic analysis, an SPPB improvement >1 was identified as the MCID (area-under-curve 0.77, 95% CI 0.67-0.85). Overall, 285 patients (74.2%) had a 'clinically significant' improvement in SPPB, with a rate of improvement higher in patients with severe/moderate limitations (83.0%) and lower in those with mild (78.9%) or minimal/no limitations (53.6%). CONCLUSION: A lower SPPB score is associated with a higher complications rate in the post-acute phase. An improvement >1 point of SPPB was identified as the MCID; this reference value could serve as the goal for rehabilitation interventions.

Update on cardiovascular prevention in clinical practice: A position paper of the European Association of Preventive Cardiology of the European Society of Cardiology.

European guidelines on cardiovascular prevention in clinical practice were first published in 1994 and have been regularly updated, most recently in 2016, by the Sixth European Joint Task Force. Given the amount of new information that has become available since then, components from the task force and experts from the European Association of Preventive Cardiology of the European Society of Cardiology were invited to provide a summary and critical review of the most important new studies and evidence since the latest guidelines were published. The structure of the document follows that of the previous document and has six parts: Introduction (epidemiology and cost effectiveness); Cardiovascular risk; How to intervene at the population level; How to intervene at the individual level; Disease-specific interventions; and Settings: where to intervene? In fact, in keeping with the guidelines, greater emphasis has been put on a population-based approach and on disease-specific interventions, avoiding re-interpretation of information already and previously considered. Finally, the presence of several gaps in the knowledge is highlighted.

Exercise gas exchange in continuous-flow left ventricular assist device recipients.

Exercise ventilation/perfusion matching in continuous-flow left ventricular assist device recipients (LVAD) has not been studied systematically. Twenty-five LVAD and two groups of 15 reduced ejection fraction chronic heart failure (HFrEF) patients with peak VO2 matched to that of LVAD (HFrEF-matched) and ≥14 ml/kg/min (HFrEF≥14), respectively, underwent cardiopulmonary exercise testing with arterial blood gas analysis, echocardiogram and venous blood sampling for renal function evaluation. Arterial-end-tidal PCO2 difference (P(a-ET)CO2) and physiological dead space-tidal volume ratio (VD/VT) were used as descriptors of alveolar and total wasted ventilation, respectively. Tricuspid annular plane systolic excursion/pulmonary artery systolic pressure ratio (TAPSE/PASP) and blood urea nitrogen/creatinine ratio were calculated in all patients and used as surrogates of right ventriculo-arterial coupling and circulating effective volume, respectively. LVAD and HFrEF-matched showed no rest-to-peak change of P(a-ET)CO2 (4.5±2.4 vs. 4.3±2.2 mm Hg and 4.1±1.4 vs. 3.8±2.5 mm Hg, respectively, both p >0.40), whereas a decrease was observed in HFrEF≥14 (6.5±3.6 vs. 2.8±2.0 mm Hg, p <0.0001). Rest-to-peak changes of P(a-ET)CO2 correlated to those of VD/VT (r = 0.70, p <0.0001). Multiple regression indicated TAPSE/PASP and blood urea nitrogen/creatinine ratio as independent predictors of peak P(a-ET)CO2. LVAD exercise gas exchange is characterized by alveolar wasted ventilation, i.e. hypoperfusion of ventilated alveoli, similar to that of advanced HFrEF patients and related to surrogates of right ventriculo-arterial coupling and circulating effective volume.

Gait speed has comparable prognostic capability to six-minute walk distance in older patients with cardiovascular disease.

Background Although gait speed and six-minute walk distance are used to assess functional capacity in older patients with cardiovascular disease, their prognostic capabilities have not been directly compared. Methods The study population was identified from the Kitasato University Cardiac Rehabilitation Database and consisted of 1474 patients ≥60 years old with a mean age of 72.2 ± 7.1 years that underwent evaluation of both usual gait speed and six-minute walk distance in routine geriatric assessment between 1 June 2008-30 September 2015. Both gait speed and six-minute walk distance were determined on the same day at hospital discharge. Results Mean gait speed and six-minute walk distance in the whole population were 1.04 m/s and 381 m, respectively, and were strongly positively correlated ( r = 0.80, p < 0.001). A total of 180 deaths occurred during a follow-up of 2.3 ± 1.9 years. After adjusting for confounding factors, both gait speed (adjusted hazard ratio per 0.1 m/s increase: 0.87, 95% confidence interval: 0.81-0.93, p < 0.001) and six-minute walk distance (adjusted hazard ratio per 10-metre increase: 0.96, 95% confidence interval: 0.94-0.97, p < 0.001) were independent predictors of all-cause mortality. There was no significant difference in prognostic capability between gait speed and six-minute walk distance (c-index: 0.64 (95% confidence interval: 0.60-0.69) and 0.66 (95% confidence interval: 0.61-0.70), respectively, p = 0.357). Conclusions Gait speed and six-minute walk distance showed similar prognostic predictive ability for all-cause mortality in older cardiovascular disease patients, indicating the potential utility of gait speed as a simple risk stratification tool in older cardiovascular disease patients.

Characteristics of structured physical training currently provided in cardiac patients: insights from the Exercise Training in Cardiac Rehabilitation (ETCR) Italian survey.

BACKGROUND: Uncertainty exists about current delivery levels of exercise training (ET) during Cardiac Rehabilitation (CR) programmes. AIM OF THE STUDY: To evaluate ET modalities in the real world of CR facilities in Italy. METHODS: This was an observational survey of aggregate data, collected from CR facilities on a voluntary basis. Snapshots of a single working day at a local site were made, in terms of characteristics of patients and ET programmes delivered. RESULTS. Overall, 612 patients from 26 CR units were included, with an in-patient vs. out-patient ratio of 3:1. Coronary artery disease (57.6%), heart failure (20.3%), and valve disease/surgery (22.1%) were the most represented target groups. The prevalence of endurance continuous training, interval training, and resistance/strength training was 66.7%, 11.1%, and 9.0%; other non-aerobic endurance and non-resistance training modalities such as respiratory muscle training and calisthenics were reported in 39.9% and 42.9% of cases respectively. Workloads for endurance exercise training were determined by cardiopulmonary test, conventional 12-leads ECG exercise testing, 6min-walking test, theoretical determination of heart rate, and rating of perceived exertion in 9%, 8%, 27%, 9%, and 40% of cases respectively. The average duration of the programmes (on an intention to treat basis) was 25 sessions of 42±11  minutes, with a frequency of >4 sessions/week in 67% of patients. CONCLUSIONS: Despite advances in CR interventions, there is a significant need for improvement of functional evaluation and exercise training prescription, and consideration of a wider range of training modalities in Italy. .

Cardiopulmonary Exercise Testing in Patients with Heart Failure with Specific Comorbidities.

Exercise capacity is one of the most powerful predicting factors of life expectancy, both in patients with and those without cardiac disease. Cardiopulmonary exercise testing provides a global assessment of the integrative exercise responses involving the pulmonary, cardiovascular, hematopoietic, neuropsychological, and skeletal muscle systems, which are not adequately reflected through the measurement of individual organ system function. This relatively noninvasive, dynamic, physiologic overview allows the evaluation of both submaximal and peak exercise responses, providing the physician with relevant information for clinical decision-making. Chronic heart failure is a significant cause of worldwide mortality and morbidity, whose clinical picture is characterized by exercise intolerance and impaired quality of life. The purpose of this review is to provide an update of the role of cardiopulmonary exercise testing in patients with heart failure with specific comorbidities. Patients with heart failure frequently present concomitant clinical conditions, such as obesity, anemia, lung or kidney disease, diabetes mellitus, cancer, depression, and psychogenic disorders, which could affect length and quality of life, including everyday activities and exercise performance. Poor effort and malingering may be suspected when early discontinuation of the exercise test with irregular breathing occurs.

Frailty and cardiac rehabilitation: A call to action from the EAPC Cardiac Rehabilitation Section.

Frailty is a geriatric syndrome characterised by a vulnerability status associated with declining function of multiple physiological systems and loss of physiological reserves. Two main models of frailty have been advanced: the phenotypic model (primary frailty) or deficits accumulation model (secondary frailty), and different instruments have been proposed and validated to measure frailty. However measured, frailty correlates to medical outcomes in the elderly, and has been shown to have prognostic value for patients in different clinical settings, such as in patients with coronary artery disease, after cardiac surgery or transvalvular aortic valve replacement, in patients with chronic heart failure or after left ventricular assist device implantation. The prevalence, clinical and prognostic relevance of frailty in a cardiac rehabilitation setting has not yet been well characterised, despite the increasing frequency of elderly patients in cardiac rehabilitation, where frailty is likely to influence the onset, type and intensity of the exercise training programme and the design of tailored rehabilitative interventions for these patients. Therefore, we need to start looking for frailty in elderly patients entering cardiac rehabilitation programmes and become more familiar with some of the tools to recognise and evaluate the severity of this condition. Furthermore, we need to better understand whether exercise-based cardiac rehabilitation may change the course and the prognosis of frailty in cardiovascular patients.

Healthy lifestyle interventions to combat noncommunicable disease-a novel nonhierarchical connectivity model for key stakeholders: a policy statement from the American Heart Association, European Society of Cardiology, European Association for Cardiovascular Prevention and Rehabilitation, and American College of Preventive Medicine.

Noncommunicable diseases (NCDs) have become the primary health concern for most countries around the world. Currently, more than 36 million people worldwide die from NCDs each year, accounting for 63% of annual global deaths; most are preventable. The global financial burden of NCDs is staggering, with an estimated 2010 global cost of $6.3 trillion (US dollars) that is projected to increase to $13 trillion by 2030. A number of NCDs share one or more common predisposing risk factors, all related to lifestyle to some degree: (1) cigarette smoking, (2) hypertension, (3) hyperglycemia, (4) dyslipidemia, (5) obesity, (6) physical inactivity, and (7) poor nutrition. In large part, prevention, control, or even reversal of the aforementioned modifiable risk factors are realized through leading a healthy lifestyle (HL). The challenge is how to initiate the global change, not toward increasing documentation of the scope of the problem but toward true action-creating, implementing, and sustaining HL initiatives that will result in positive, measurable changes in the previously defined poor health metrics. To achieve this task, a paradigm shift in how we approach NCD prevention and treatment is required. The goal of this American Heart Association/European Society of Cardiology/European Association for Cardiovascular Prevention and Rehabilitation/American College of Preventive Medicine policy statement is to define key stakeholders and highlight their connectivity with respect to HL initiatives. This policy encourages integrated action by all stakeholders to create the needed paradigm shift and achieve broad adoption of HL behaviors on a global scale.

Healthy Lifestyle Interventions to Combat Noncommunicable Disease­A Novel Nonhierarchical Connectivity Model for Key Stakeholders: A Policy Statement From the American Heart Association, European Society of Cardiology, European Association for Cardiovascular Prevention and Rehabilitation, and American College of Preventive Medicine.

Noncommunicable diseases (NCDs) have become the primary health concern for most countries around the world. Currently, more than 36 million people worldwide die from NCDs each year, accounting for 63% of annual global deaths; most are preventable. The global financial burden of NCDs is staggering, with an estimated 2010 global cost of $6.3 trillion (US dollars) that is projected to increase to $13 trillion by 2030. A number of NCDs share one or more common predisposing risk factors, all related to lifestyle to some degree: (1) cigarette smoking, (2) hypertension, (3) hyperglycemia, (4) dyslipidemia, (5) obesity, (6) physical inactivity, and (7) poor nutrition. In large part, prevention, control, or even reversal of the aforementioned modifiable risk factors are realized through leading a healthy lifestyle (HL). The challenge is how to initiate the global change, not toward increasing documentation of the scope of the problem but toward true action-creating, implementing, and sustaining HL initiatives that will result in positive, measurable changes in the previously defined poor health metrics. To achieve this task, a paradigm shift in how we approach NCD prevention and treatment is required. The goal of this American Heart Association/European Society of Cardiology/European Association for Cardiovascular Prevention and Rehabilitation/American College of Preventive Medicine policy statement is to define key stakeholders and highlight their connectivity with respect to HL initiatives. This policy encourages integrated action by all stakeholders to create the needed paradigm shift and achieve broad adoption of HL behaviors on a global scale.

Secondary prevention through cardiac rehabilitation: physical activity counselling and exercise training: key components of the position paper from the Cardiac Rehabilitation Section of the European Association of Cardiovascular Prevention and Rehabilitation.

Cardiac patients after an acute event and/or with chronic heart disease deserve special attention to restore their quality of life and to maintain or improve functional capacity. They require counselling to avoid recurrence through a combination of adherence to a medication plan and adoption of a healthy lifestyle. These secondary prevention targets are included in the overall goal of cardiac rehabilitation (CR). Cardiac rehabilitation can be viewed as the clinical application of preventive care by means of a professional multi-disciplinary integrated approach for comprehensive risk reduction and global long-term care of cardiac patients. The CR approach is delivered in tandem with a flexible follow-up strategy and easy access to a specialized team. To promote implementation of cardiac prevention and rehabilitation, the CR Section of the EACPR (European Association of Cardiovascular Prevention and Rehabilitation) has recently completed a Position Paper, entitled 'Secondary prevention through cardiac rehabilitation: A condition-oriented approach'. Components of multidisciplinary CR for seven clinical presentations have been addressed. Components include patient assessment, physical activity counselling, exercise training, diet/nutritional counselling, weight control management, lipid management, blood pressure monitoring, smoking cessation, and psychosocial management. Cardiac rehabilitation services are by definition multi-factorial and comprehensive, with physical activity counselling and exercise training as central components in all rehabilitation and preventive interventions. Many of the risk factor improvements occurring in CR can be mediated through exercise training programmes. This call-for-action paper presents the key components of a CR programme: physical activity counselling and exercise training. It summarizes current evidence-based best practice for the wide range of patient presentations of interest to the general cardiology community.

Exercise intolerance in chronic heart failure: mechanisms and therapies. Part I.

Muscular fatigue and dyspnoea on exertion are among the most common symptoms in chronic heart failure; however their origin is still poorly understood. Several studies have shown that cardiac dysfunction alone cannot fully explain their origin, but the contribution of the multiorgan failure present in this syndrome must be highlighted. In this study, divided in two parts (see part II: pp. 643­648), we aimed to summarize the existing evidence and the most controversial aspects of the complex interplay of different factors involved in symptom generation. In this first part of the review, six key factors are revised: the heart, the lung, the skeletal muscle, the hormonal changes, the O2 delivery to the periphery, the endothelium. In the second part, the role of the excitatory reflexes and the cardiac cachexia will be presented, and finally, the potential therapeutic implications are discussed. We believe that a better knowledge of the pathophysiology of this syndrome may contribute to the management of the patients and to the improvement in their stress tolerance and quality of life.

Exercise intolerance in chronic heart failure: mechanisms and therapies. Part II.

Muscular fatigue and dyspnoea on exertion are among the most common symptoms in chronic heart failure; however their origin is still poorly understood. Several studies have shown that cardiac dysfunction alone cannot fully explain their origin, but the contribution of the multiorgan failure present in this syndrome must be highlighted. We aimed to summarize the existing evidence and the most controversial aspects of the complex interplay of different factors involved in the symptom generation. In the first part of the review, six key factors were revised (the heart, the lung, the skeletal muscle, the hormonal changes, the O2 delivery to the periphery, the endothelium). In this second part, the role of the excitatory reflexes and the cardiac cachexia are presented. Finally, potential therapeutic implications are discussed here. We believe that a better knowledge of the pathophysiology of this syndrome may contribute to the management of the patients and to the improvement in their stress tolerance and quality of life.