Promoting Patient Utilization of Outpatient Cardiac Rehabilitation: A JOINT INTERNATIONAL COUNCIL AND CANADIAN ASSOCIATION OF CARDIOVASCULAR PREVENTION AND REHABILITATION POSITION STATEMENT Purpose: Cardiac rehabilitation (CR) is a recommendation in international clinical practice guidelines given its benefits; however, use is suboptimal. The purpose of this position statement was to translate evidence on interventions that increase CR enrollment and adherence into implementable recommendations. Methods: The writing panel was constituted by representatives of societies internationally concerned with preventive cardiology and included disciplines that would be implementing the recommendations. Patient partners served, as well as policy makers. The statement was developed in accordance with AGREE II, among other guideline checklists. Recommendations were based on our update of the Cochrane review on interventions to promote patients' utilization of CR. These were circulated to panel members, who were asked to rate each on a 7-point Likert scale in terms of scientific acceptability, actionability, and feasibility of assessment. A Web call was convened to achieve consensus and confirm strength of the recommendations (based on Grading of Recommendations Assessment, Development, and Evaluation [GRADE]). The draft underwent external review and public comment. Results: The 3 drafted recommendations were that to increase enrollment, health care providers, particularly nurses (strong), should promote CR to patients face-to-face (strong), and that to increase adherence, part of CR could be delivered remotely (weak). Ratings (mean ± SD) for the 3 recommendations were 5.95 ± 0.69, 5.33 ± 1.12, and 5.64 ± 1.08, respectively. Conclusions: Interventions can significantly increase utilization of CR and hence should be widely applied. We call upon cardiac care institutions to implement these strategies to augment CR utilization and to ensure that CR programs are adequately resourced to serve enrolling patients and support them to complete programs. Correspondence: Sherry L. Grace, PhD, FCCS, CRFC, School of Kinesiology and Health Science, York University, Bethune 368, 4700 Keele St, Toronto, ON M3J 1P3, Canada (sgrace@yorku.ca). Endorsed by American Society for Preventive Cardiology, Association Francophone de Cardiologie Préventive, Australian Cardiovascular Health and Rehabilitation Association, Brazilian Association of Cardiorespiratory and Intensive Care Physiotherapy, Brazilian Group of Cardiopulmonary and Metabolic Rehabilitation, British Association for Cardiovascular Prevention and Rehabilitation, Canadian Association of Cardiovascular Prevention and Rehabilitation, Canadian Cardiovascular Society, Canadian Council of Cardiovascular Nurses, Cardiac Health Foundation of Canada, Cardiac Society Brunei Darussalam, Indonesian Heart Association, International Council of Cardiovascular Prevention and Rehabilitation, International Society of Physical and Rehabilitation Medicine, Iranian Heart Foundation, Grupo Latinoamericano de Trabajo en Prevencion y Rehabilitacion Cardiaca, Nepal Physiotherapy Society, Philippine Heart Association, Preventive Cardiovascular Nurses Association, Russian National Society of Preventive Cardiology, Society of Indian Physiotherapists, South African Sports Medicine Association, and Taiwan Academy of Physical Medicine and Rehabilitation. All authors declare no conflicts of interest. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Web site (www.jcrpjournal.com). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Pathophysiology of Exercise Intolerance and Its Treatment With Exercise-Based Cardiac Rehabilitation in Heart Failure With Preserved Ejection Fraction Heart failure with preserved ejection fraction (HFpEF) is the fastest growing form of heart failure in the United States. The cardinal feature of HFpEF is reduced exercise tolerance (peak oxygen uptake, VO2peak) secondary to impaired cardiac, vascular, and skeletal muscle function. There are currently no evidence-based drug therapies to improve clinical outcomes in patients with HFpEF. In contrast, exercise training is a proven effective intervention for improving VO2peak, aerobic endurance, and quality of life in HFpEF patients. This brief review discusses the pathophysiology of exercise intolerance and the role of exercise training to improve VO2peak in clinically stable HFpEF patients. It also discusses the mechanisms responsible for the exercise training–mediated improvements in VO2peak in HFpEF. Finally, it provides evidence-based exercise prescription guidelines for cardiac rehabilitation specialists to assist them with safely implementing exercise-based cardiac rehabilitation programs for HFpEF patients. Correspondence: Corey R. Tomczak, PhD, Russ Kisby Physical Activity and Health Promotion Laboratory: Integrative Cardiovascular Physiology Research Program, College of Kinesiology, University of Saskatchewan, 87 Campus Dr, Saskatoon, SK S7N 5B2, Canada (corey.tomczak@usask.ca). The authors declare no conflicts of interest. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Role of Left Ventricle Function in Cardiac Rehabilitation Outcomes in Stage B Heart Failure Patients Purpose: To study the role of left ventricle systolic function in cardiac rehabilitation program (CRP) response in stage B heart failure patients. Methods: A retrospective analysis was completed of 691 patients with previous myocardial infarction that underwent a CRP, classified in 3 groups: preserved ejection fraction (pEF), mid-range ejection fraction (mrEF), and reduced ejection fraction (rEF). We compared the response to CRP analyzing the relative changes of estimated cardiorespiratory fitness (CRFe), resting heart rate (HR), and chronotropic index (CI). Results: After exercise training (median [interquartile range]) mrEF (23.9% [9.7, 40.8]) and rEF (23.9% [9.7, 41.2]) groups had a better CRFe response to CRP than pEF groups (17.6% [0.0, 35.9]), P = .009. CI increased similarly in all groups. We found a small effect of CRP on resting HR. Conclusion: Exercise-based CRP yields notable benefits to mrEF and rEF groups and the magnitude of its benefits is, at least, similar to that found in pEF patients. Correspondence: Marta Braga, MD, Serviço de Cardiologia, Centro Hospitalar São João, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal (martabraga.hsj@gmail.com). Supplemental digital content is available for this article. Direct URL citation appears in the printed text and is provided in the HTML and PDF versions of this article on the journal's Web site (www.jcrpjournal.com). The authors declare no conflicts of interest. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Physiological Responses to the 6-min Step Test in Patients With Chronic Obstructive Pulmonary Disease Purpose: To describe physiological responses during the 6-min step test (6MST) in patients with chronic obstructive pulmonary disease (COPD), to investigate whether COPD severity and test interruptions could determine different physiological responses, and to test the reproducibility of 6MST performance. Methods: Cross-sectional study. Patients with moderate to very severe COPD underwent lung function assessment and 2 6MSTs, with physiological responses measurement by a gas analyzer and a near-infrared spectroscopy device. Results: Thirty-six patients (29 men; forced expiratory volume in the first second of expiration [FEV1] = 51.1 ± 13.6%pred) participated in the study. Most of the physiological variables stabilized between the second and fourth minutes of the 6MST, except the respiratory rate and heart rate (HR), which stabilized after the fifth minute. The patients who interrupted the 6MST showed higher minute ventilation to maximal voluntary ventilation ratio (VE/MVV; all test minutes) and HR (first and second minutes) (P < .05) and worse pulmonary function (FEV1 = 1.37 ± 0.37 L vs 1.82 ± 0.41 L, P = .002, and 47.2 ± 13.2%pred vs 56.6 ± 12.4%pred, P = .04, respectively) than those who did not interrupt the 6MST. However, their performance was similar (P = .11). 6MST performance and physiological variables were reproducible, and there was a learning effect of 6.28%. Conclusions: The 6MST showed a stabilization of the most physiological variables. In addition, interruptions were usually made by patients with a greater impairment of lung function and they presented greater increased ventilatory demand during the 6MST. However, these interruptions do not interfere with 6MST physiological responses. Moreover, the 6MST is a reliable test to evaluate the functional capacity of patients with COPD. Correspondence: Anamaria F. Mayer, PhD, Núcleo de Assistência, Ensino e Pesquisa em Reabilitação Pulmonar—NuReab, Universidade do Estado de Santa Catarina, Rua Pascoal Simone, 358. CEP 88080-350, Florianópolis-SC, Brazil (anamaria.mayer@udesc.br). The authors certify that there are no conflicts of interest with any financial organization regarding the material discussed in this article. All authors have read and approved the manuscript. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Effect of Home-Based Cardiac Rehabilitation in a Lower-Middle Income Country: RESULTS FROM A CONTROLLED TRIAL Purpose: Cardiovascular disease is the leading cause of mortality and morbidity in lower-middle income countries (LMICs), including Bangladesh. Cardiac rehabilitation (CR) as part of secondary prevention of cardiovascular disease has been shown to reduce mortality and morbidity and improve quality of life and exercise capacity. However, to date, very few controlled trials of CR have been conducted in LMICs. Methods: A quasi-randomized controlled trial comparing home-based CR plus usual care with usual care alone was undertaken with patients following coronary artery bypass graft surgery. Participants in the CR group received an in-hospital CR class and were introduced to a locally developed educational booklet with details of a home-based exercise program and then received monthly telephone calls for 12 mo. Primary outcomes were coronary heart disease (CHD) risk factors, health-related quality of life (HRQOL), and mental well-being. Maximal oxygen uptake as a measure of exercise capacity was a secondary outcome. Results: In total, 142 of 148 eligible participants took part in the trial (96%); 71 in each group. At 12-mo follow-up, 61 patients (86%) in the CR group and 40 (56%) in the usual care group provided complete outcome data. Greater reductions in CHD risk factors and improvements in HRQOL, mental well-being, and exercise capacity were seen for the CR group compared with the usual care group. Conclusions: In the context of a single-center LMIC setting, this study demonstrated the feasibility of home-based CR programs and offers a model of service delivery that could be replicated on a larger scale. Correspondence: Vicky L. Joshi, MSc, Danish Knowledge Centre for Rehabilitation and Palliative Care (REHPA), Odense University Hospital and University of Southern Denmark, Studiestrade 6, 1455, Copenhagen, Denmark (victoria.louise.joshi@rsyd.dk). All authors have read and approved the manuscript. The authors declare no conflicts of interest. Supplemental digital content is available for this article. Direct URL citation appears in the printed text and is provided in the HTML and PDF versions of this article on the journal's Web site (www.jcrpjournal.com). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Diagnostic Validity of Cardiopulmonary Exercise Testing for Screening Pulmonary Hypertension in Patients With Chronic Obstructive Pulmonary Disease Purpose: To determine diagnostic validity of cardiopulmonary exercise testing (CPX) parameters for detecting pulmonary hypertension (PH) in patients with chronic obstructive pulmonary disease (COPD) and to investigate association between CPX parameters and indices of PH. Methods: This cross-sectional study enrolled 48 moderate to very severe COPD patients in whom PH was confirmed by echocardiography. Symptom-limited CPX was performed using an incremental exercise protocol. Relevant CPX parameters were derived and were tested for their diagnostic ability for diagnosing PH. Logistic regression was applied to examine the effect of various clinical covariates on the diagnostic ability of exercise test variables for detecting PH. Results: Of the 48 patients, 29 were diagnosed with PH and 19 were negative for PH based on echocardiographic testing. CPX measures including peak oxygen uptake (% predicted VO2peak, VO2peak [mL/min], VO2/kg), oxygen pulse (VO2/HR % predicted, VO2/HR mL/beat), and peak minute ventilation (VEpeak [L/m]) were inversely correlated with mean pulmonary arterial pressure (mPAP). Peak VO2/HR and VO2peak were found to be significant predictors of PH in univariate analysis. VO2peak (%), VO2/HR (mL/beat), and desaturation (%) were identified as independent predictors of PH adjusted for age, forced expiratory volume in 1 sec (%), and forced vital capacity (L). Conclusion: The present study validates the use of CPX parameters such as VO2peak and VO2/HR as a diagnostic tool for correctly identifying PH in COPD patients. Therefore, CPX may be used as an adjunct to echocardiographic measurement of PH where there is unavailability of equipment and expertise. Correspondence: Jamal Ali Moiz, PhD, MPT, Centre for Physiotherapy and Rehabilitation Sciences, Jamia Millia Islamia, New Delhi 110 025, India (jmoiz@jmi.ac.in). Conflict of Interest: None. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Type 2 Diabetes Mellitus, Glycated Hemoglobin Levels, and Cardiopulmonary Exercise Capacity in Patients With Ischemic Heart Disease Purpose: Diabetes mellitus (DM) is associated with long-term cardiovascular complications, including ischemic heart disease (IHD). Nonetheless, DM may directly impair myocardial and lung structure and function. The aim of this study was to assess the impact of type 2 DM (T2DM) and glycemic control on cardiopulmonary exercise capacity in patients with IHD. Methods: The study involved a cross-sectional analysis of 91 consecutive patients (57 ± 10 yr, 90% men) who underwent a cardiopulmonary exercise test at the beginning of an exercise-based standard phase-II cardiac rehabilitation program, 2 to 3 mo after an acute coronary syndrome. Association of T2DM with cardiopulmonary exercise test parameters was assessed using multiple linear regression analysis controlling for prespecified potential confounders. Results: There were 26 (29%) diabetic subjects among IHD patients included in the study. After adjustment, T2DM was an independent predictor of a reduced peak oxygen uptake (VO2peak) (P = .005), a reduced pulse O2 trajectory (P = .001), a steeper minute ventilation to carbon dioxide output (VE/VCO2) slope (P = .046), and an increased dead space-to-tidal volume ratio (VD/VT) at peak exercise (P = .049). Glycated hemoglobin (HbA1c) levels were significantly associated with a reduced forced expiratory volume in the first second of expiration (FEV1) (P = .013), VE (P = .001), and VT (P = .007). VO2peak (P trend < .001), VO2 at anaerobic threshold (P trend < .001), and pulse O2 trajectory (P trend < .001) decreased among HbA1c tertiles. Conclusions: Patients with IHD and a previous diagnosis of T2DM had a reduced aerobic capacity and a ventilation-perfusion mismatch compared with nondiabetic patients. Poor glycemic control in men further deteriorates aerobic capacity probably due to ventilatory inefficiency. Correspondence: Ramón Arroyo-Espliguero, MD, PhD, Department of Cardiology, University Hospital, Guadalajara, Spain, C/Donantes de Sangre, s/n Guadalajara, 19002 (rarroyo@sescam.jccm.es). The authors report no relationships with respect to the research, authorship, and/or publication of this article that could be construed as a conflict of interest. Supplemental digital content is available for this article. Direct URL citation appears in the printed text and is provided in the HTML and PDF versions of this article on the journal's Web site (www.jcrpjournal.com). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

The Effect and Safety of Aerobic Interval Training According to Exercise Intensity in Acute Coronary Syndrome Purpose: To evaluate the effect of increasing the maximal oxygen uptake (VO2max) and the safety of maximal-intensity aerobic interval training (MAIT) compared with high-intensity aerobic interval training (HAIT). Methods: Forty-seven patients with first-ever acute coronary syndrome were assigned to MAIT or HAIT. Subjects underwent adaptation period during the first 2 wk of cardiac rehabilitation and then MAIT at 95-100% of the heart rate reserve or HAIT at 85% of the heart rate reserve, 3 d/wk for 4 wk. The primary outcome was VO2max. The secondary outcomes were major cardiovascular complications, hemodynamic responses, myocardial oxygen demand, cardiometabolic health, and echocardiographic findings. Results: A total of 670.5 hr of MAIT and HAIT were completed. After 6 wk of aerobic interval training, VO2max was significantly increased in both groups. However, the increment of VO2max was significantly greater in the MAIT group than in the HAIT group (P < .05). The percentage increases for MAIT and HAIT were 31% and 17%, respectively. No major cardiovascular or musculoskeletal complications were noted. Conclusions: The results of this study indicate that 6 wk of MAIT resulted in statistically significantly better improvement in VO2max than 6 wk of HAIT at a similar total work in patients with acute coronary syndrome. Moreover, both MAIT and HAIT may be safe to use in the cardiac rehabilitation setting. Correspondence: Hee Eun Choi, MD, Department of Rehabilitation Medicine, Haeundae Paik Hospital, Inje University College of Medicine, 875, Haeun-daero, Haeundae-gu, Busan, Korea (solideogloria@paik.ac.kr). The authors declare no conflicts of interest. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Web site (www.jcrpjournal.com). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Pedometer Feedback Interventions Increase Daily Physical Activity in Phase III Cardiac Rehabilitation Participants Purpose: To determine the effects of individually tailored interventions designed to increase physical activity (PA) in cardiac patients. Methods: A total of 99 (77 men and 22 women, 61.5 ± 10.7 yr) patients entering a phase III cardiac rehabilitation program completed a 12-wk PA intervention. Patients were randomized to usual care (UC, time-based recommendation), pedometer feedback (PF), newsletter-based motivational messaging (MM), or PF + MM. Both PF groups were given a goal of increasing steps/d by 10% of individual baseline value each week. If the goal for the week was not reached, the same goal was used for the next week. Physical activity was assessed for 7 d before beginning and after completing the program. The change in steps/d, moderate to vigorous intensity PA minutes, and sedentary time were compared among intervention groups. Results: Average change in steps/d was found to be significantly greater (P < .01) in the PF (2957 ± 3185) and the PF + MM (3150 ± 3007) compared with UC (264 ± 2065) and MM (718 ± 2415) groups. No group experienced changes in moderate to vigorous intensity PA time and only the PF intervention group decreased sedentary time (baseline 470.2 ± 77.1 to postintervention 447.8 ± 74.9 min/d, P = .01). Conclusion: The findings from this study demonstrate that using PF was superior to the usual time–based PA recommendations and to newsletter-based MM in patients starting a phase III CR program. Cardiac rehabilitation programs are encouraged to implement PA feedback with individualized PA goals in order to support the increase in PA. Correspondence: Cemal Ozemek, PhD, FACSM, ACSM-CEP, RCEP, Department of Physical Therapy, College of Applied Health Sciences, The University of Illinois at Chicago, 1919 W Taylor St, Chicago, IL 60612 (ozemek@uic.edu). The authors declare no conflicts of interest. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Low-Volume High-Intensity Aerobic Interval Training Is an Efficient Method to Improve Cardiorespiratory Fitness After Myocardial Infarction: PILOT STUDY FROM THE INTERFARCT PROJECT Purpose: To analyze the changes in cardiorespiratory fitness (CRF) and body composition following 2 different (low-volume vs high-volume) high-intensity aerobic interval training (HIIT) programs with Mediterranean diet (Mediet) recommendations in individuals after myocardial infarction (MI) and compared with an attention control group (AC). Methods: Body composition and CRF were assessed before and after a 16-wk intervention in 70 participants (58.4 ± 8.5 yr) diagnosed with MI. All participants received Mediet recommendations and were randomly assigned to the AC group (physical activity recommendations, n = 14) or one of the 2 supervised aerobic exercise groups (2 d/wk training): high-volume (40 min) HIIT (n = 28) and low-volume (20 min) HIIT (n = 28). Results: Following the intervention, no significant changes were seen in the AC group and no differences between HIIT groups were found in any of the studied variables. Only HIIT groups showed reductions in waist circumference (low-volume HIIT, Δ=−4%, P < .05; high-volume HIIT, Δ=−2%, P < .001) and improvements in CRF (low-volume HIIT, Δ= 15%, P < .01; high-volume HIIT, Δ= 22%; P < .001) with significant between-group differences (attention control vs HIIT groups). Conclusions: Results suggest that a 16-wk intervention (2 d/wk) of different HIIT volumes with Mediet recommendations could equally improve CRF and waist circumference after MI. Low-volume HIIT may be a potent and time-efficient exercise training strategy to improve functional capacity. Correspondence: Sara Maldonado-Martín, PhD, Physical Activity and Sport Science Section, Department of Physical Education and Sport, Faculty of Education and Sport, University of the Basque Country (UPV/EHU), Portal de Lasarte, 71, 01007 Vitoria-Gasteiz (Araba/Alava)-Basque Country, Spain (sara.maldonado@ehu.eus). The authors declare no conflicts of interest. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal's Web site (www.jcrpjournal.com). Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.