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.

Effect of Initiating Cardiac Rehabilitation After Myocardial Infarction on Subsequent Hospitalization in Older Adults Purpose: Outpatient cardiac rehabilitation (CR) participation after myocardial infarction (MI) reduces all-cause mortality; however, less is known about effects of CR on post-MI hospitalization. The study objective was to investigate effects of CR on hospitalization following acute MI among older adults. Methods: Medicare beneficiaries aged 65 to 88 yr hospitalized in 2008 with acute MI, who survived at least 60 d post-discharge, had a revascularization procedure during index hospitalization, and did not have an MI in previous year were eligible for this study. CR initiation was assessed in the 60 d post-discharge. Competing risk survival analysis was used to estimate the proportion of discharged beneficiaries hospitalized between the end of 60-d exposure window and December 31, 2009, treating death as a competing event. Results: The mean ± SD age of 32 851 Medicare beneficiaries meeting study criteria was 75 ± 6.0 yr, approximately half were male (52%), and the majority were white (88%). In this study, 21% of beneficiaries initiated CR within the exposure window. At 1 yr post-discharge, CR initiators had a lower risk of recurrent MI (4.2% [95% CI, 3.5-5.1]), cardiovascular (15.7% [95% CI, 14.3-17.2]), and all-cause (30.4% [95% CI, 28.8-32.1]) hospitalization than noninitiators (5.2% [95% CI, 5.0-5.5]; 18.0% [95% CI, 17.6-18.4]; and 33.2% [95% CI, 32.5-33.8], respectively). There was no difference in fracture risk (negative control outcome). Conclusions: This study provides evidence that CR can reduce the 1-yr risk of cardiovascular and all-cause hospital admissions in Medicare aged MI survivors. Correspondence: Montika Bush, PhD, Department of Emergency Medicine, School of Medicine, University of North Carolina, Chapel Hill, 170 Manning Dr, CB# 7594, Chapel Hill, NC 27599 (mbush8@unc.edu). Dr Stürmer receives investigator-initiated research funding and support as Principal Investigator (R01 AG056479) from the National Institute on Aging and as coinvestigator (R01 HL118255, R01 MD011680) from the National Institutes of Health (NIH). He also receives salary support as Director of Comparative Effectiveness Research (CER), NC TraCS Institute, UNC Clinical and Translational Science Award (UL1TR002489), the Center for Pharmacoepidemiology (current members: GlaxoSmithKline, UCB BioSciences, Merck, Takeda), from pharmaceutical companies (GSK, Amgen, AstraZeneca, Novo Nordisk), and from a generous contribution from Dr Nancy A. Dreyer to the Department of Epidemiology, University of North Carolina at Chapel Hill. Dr Stürmer does not accept personal compensation of any kind from any pharmaceutical company. He owns stock in Novartis, Roche, BASF, AstraZeneca, and Novo Nordisk. Dr Brookhart has received investigator-initiated research funding and support as Principal Investigator (NIH, R21 HD080214, R01 AG023178, R01 AG056479); as co-Investigator from the Agency for Healthcare Research, Patient Centered Outcomes Research Institute, AstraZeneca, and Amgen; honoraria paid via UNC for scientific advisory from Merck, GSK, Pfizer, and World Health Information Consultants; and consulting fees from RxAnte. The author others 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.

Characterization of Dyspnea in Veteran Lung Cancer Survivors Following Curative-Intent Therapy Purpose: Dyspnea is highly prevalent in lung cancer survivors following curative-intent therapy. We aimed to identify clinical predictors or determinants of dyspnea and characterize its relationship with functional exercise capacity (EC). Methods: In an analysis of data from a cross-sectional study of lung cancer survivors at the VA San Diego Healthcare System who completed curative-intent therapy for stage I-IIIA disease ≥1 mo previously, we tested a thorough list of comorbidities, lung function, and lung cancer characteristics. We assessed dyspnea using the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire Lung Cancer Module 13 (LC13) and functional EC using the 6-minute walk. We replicated results with the University of California San Diego Shortness of Breath Questionnaire. Results: In 75 participants at a median of 12 mo since treatment completion, the mean ± SD LC13-Dyspnea score was 35.3 ± 26.2; 60% had abnormally high dyspnea. In multivariable linear regression analyses, significant clinical predictors or determinants of dyspnea were (β [95% CI]) psychiatric illness (−20.8 [−32.4 to −9.09]), heart failure with reduced ejection fraction (−15.5 [−28.0 to −2.97]), and forced expiratory volume in the first second of expiration (−0.28 [−0.49 to −0.06]). Dyspnea was an independent predictor of functional EC (−1.54 [−2.43 to −0.64]). These results were similar with the University of California San Diego Shortness of Breath Questionnaire. Conclusion: We identified clinical predictors or determinants of dyspnea that have pathophysiological bases. Dyspnea was independently associated with functional EC. These results have implications in efforts to reduce dyspnea and improve exercise behavior and functional EC in lung cancer survivors following curative-intent therapy. Correspondence: Duc Ha, MD, MAS; Institute for Health Research, Kaiser Permanente Colorado, 2550 S Parker Rd Ste 200, Aurora, CO 80014 (duc.m.ha@kp.org). This work was supported directly by the American Cancer Society (PF-17-020-01-CPPB) and the National Institutes of Health (1T32HL134632-01 from the NHLBI) and indirectly by the National Cancer Institute (L30CA208950). 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.

Cardiopulmonary Exercise Testing Following Open Repair for a Proximal Thoracic Aortic Aneurysm or Dissection Purpose: There are limited data on cardiopulmonary exercise testing (CPX) and cardiorespiratory fitness (CRF), following open repair for a proximal thoracic aortic aneurysm or dissection. The aim was to evaluate serious adverse events, abnormal CPX event rate, CRF (peak oxygen uptake, Vo2peak), and blood pressure. Methods: Patients were retrospectively identified from cardiac rehabilitation participation or prospectively enrolled in a research study and grouped by phenotype: (1) bicuspid aortic valve/thoracic aortic aneurysm, (2) tricuspid aortic valve/thoracic aortic aneurysm, and (3) acute type A aortic dissection. Results: Patients (n = 128) completed a CPX a median of 2.9 mo (interquartile range: 1.8, 3.5) following repair. No serious adverse events were reported, although 3 abnormal exercise tests (2% event rate) were observed. Eighty-one percent of CPX studies were considered peak effort (defined as respiratory exchange ratio of ≥1.05). Median measured Vo2peak was <36% predicted normative values (19.2 mL·kg−1.min−1 vs 29.3 mL·kg−1·min−1, P < .0001); the most marked impairment in Vo2peak was observed in the acute type A aortic dissection group (<40% normative values), which was significantly different from other groups (P < .05). Peak exercise systolic and diastolic blood pressures were 160 mm Hg (144, 172) and 70 mm Hg (62, 80), with no differences noted between groups. Conclusions: We observed no serious adverse events with an abnormal CPX event rate of only 2% 3 mo following repair for a proximal thoracic aortic aneurysm or dissection. Vo2peak was reduced among all patient groups, especially the acute type A aortic dissection group, which may be clinically significant, given the well-established prognostic importance of reduced cardiorespiratory fitness. Correspondence: Bo Yang, MD, PhD, Department of Cardiac Surgery, University of Michigan, Michigan Medicine, 1500 East Medical Center Dr, 5155 Frankel Cardiovascular Center, Ann Arbor, MI, 48109 (boya@med.umich.edu). External financial support: Bo Yang is supported by the National Institutes of Health (K08HL130614 and R01HL141891) and The Phil Jenkins and Darlene & Stephen J. Szatmari Funds. Cristen J. Willer is supported by the National Institutes of Health (R01-HL127564, R35-HL135824, and R01-HL142023). Himanshu J. Patel is supported by The Joe D. Morris Collegiate Professorship, the David Hamilton Fund, and the Phil Jenkins Breakthrough Fund in Cardiac Surgery. Kim A. Eagle is consultant for NHLBI and has a research grant from Gore. Lee W. Jones is supported by the National Cancer Institute, AKTIV Against Cancer, and the Kavli Trust. Sara Saberi is the site principal investigator for 2 clinical trials funded by Myokardia and receives financial support from Myokardia. Internal financial support: Whitney E. Hornsby, Bo Yang, Cristen J. Willer, and Sara Saberi are supported by the University of Michigan, Michigan Medicine, Frankel Cardiovascular Center, Aikens Fund for Aortic Research. Himanshu J. Patel is a consultant for WL gore Edwards and Medtronic. All other 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.

Aerobic Exercise Effects on Quality of Life and Psychological Distress After an Implantable Cardioverter Defibrillator Purpose: The purpose of this study was to evaluate quality of life (QOL), psychological function, and self-efficacy outcomes in the Anti-Arrhythmic Effects of Exercise After an ICD Trial. Methods: In the Anti-Arrhythmic Effects of Exercise After an ICD Trial, 160 patients (124 men and 36 women) who had an implantable cardioverter defibrillator for primary (43%) or secondary (57%) prevention were randomized to exercise (EX, n = 84) or usual care (UC, n = 76). The EX consisted of 8 wk of home walking 1 hr/d 5 d/wk, followed by 16 wk of maintenance home walking for 150 min/wk. Adherence was determined from exercise logs, ambulatory HR recordings, and phone calls. Assessments were conducted at baseline, 8, and 24 wk for QOL: Patient Concerns Assessment and Short Form-36; anxiety: State Trait Anxiety Inventory; depression: Physician Health Questionnaire-Depression; and self-efficacy: Self-Efficacy for Walking Scale. Results: Participants averaged 55 ± 12 yr of age with ejection fraction = 40.6 ± 15.7%. The EX significantly decreased depression severity (EX: 1.33 ± 0.64; UC: 1.51 ± 0.86, P = .05) and improved self-efficacy (EX: 7.65 ± 1.97; UC: 6.85 ± 2.40, P = .05) at 8 wk. There were no significant effects at 24 wk. Adherent exercisers had significant improvements in QOL, psychological, and self-efficacy outcomes at 8 and 24 wk compared with those who were nonadherent. There were no implantable cardioverter defibrillator shocks associated with exercise. Conclusions: The EX conferred significant effects on depression and self-efficacy at 8 wk, without effects on QOL. Adherent exercisers experienced significant improvements in outcomes over those who were nonadherent or received UC. Correspondence: Cynthia M. Dougherty, ARNP, PhD, University of Washington, School of Nursing, Box 357266, 1959 NE Pacific St, HSB T615A, Seattle, WA 98195 (cindyd@uw.edu). The authors declare no conflicts of interest. Clinical Trial Registration Information: ClinicalTrials.gov number: NCT 00522340, https://trialbulletin.com/lib/entry/ct-00522340 Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Functional and Cardiovascular Measurements in Patients With Peripheral Artery Disease: COMPARISON BETWEEN MEN AND WOMEN Purpose: To compare functional and cardiovascular variables of men and women with peripheral artery disease (PAD). Methods: This observational, cross-sectional study included 67 women and 144 men (age 66 ± 9 and 67 ± 10 yr, respectively) with PAD. Patients were submitted to a clinical evaluation, 6-min walk test (6MWT) and cardiovascular evaluation, including blood pressure, arterial stiffness variables, and heart rate variability. Results: Women had lower claudication onset distance (P = .033) and 6MWT distance (P < .001), and similar percentage of the predicted 6MWT distance (P > .05). Women had higher pulse pressure (P = .002), augmentation index (P < .001), augmentation index corrected by 75 bpm (P < .001), and brachial and central systolic blood pressure (P = .041 and P = .029). Diastolic blood pressure, pulse wave velocity, and heart rate variability were similar between sexes (P > .05). Conclusion: Although predicted 6MWT performance was similar between sexes, women had higher blood pressure and wave reflection variables compared with men. Interventions to reduce blood pressure and wave reflection should be emphasized in women with PAD. Correspondence: Raphael M. Ritti-Dias, PhD, Universidade Nove de Julho, São Paulo, SP, Brazil (raphaelritti@gmail.com) The authors declare no conflicts of interest. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Wearable Cardioverter Defibrillator–Guided 6-Min Walk Test Performed at Home Is Accurate and Reliable: RESULTS OF THE TRENDS STUDY Purpose: The 6-min walk test (6MWT) is broadly used to evaluate the functional ability of patients with heart failure (HF). The purpose of this study was to evaluate the accuracy and reliability of the wearable cardioverter defibrillator (WCD)–guided 6MWT performed at home by patients with HF versus in-clinic testing. Methods: Patients (n = 197) with HF and a low ejection fraction prescribed a WCD were randomized to 2 groups. Group 1 completed an in-clinic clinician-guided 6MWT while wearing the WCD; results were recorded by the clinician. Group 2 completed a WCD-guided 6MWT, also performed in the clinic; results were recorded by the WCD accelerometer. Both groups performed weekly unsupervised WCD-guided 6MWTs at home, with results recorded by the WCD. Results: The initial in-clinic 6MWT showed no significant group difference in distance walked (group 1 = 306 m; group 2 = 297 m). For patients in group 2 who completed at least one 6MWT at home, there was a 15-step decrease between the in-clinic WCD-guided 6MWT and the first at-home 6MWT, 558 and 543 median steps (P = .001), respectively. Among patients with at least 8 weekly home WCD-guided 6MWTs (n = 70), there was no significant difference in the number of steps walked during the 6MWT from week to week. Conclusions: Results of the in-clinic 6MWT are similar between clinician-guided and WCD-guided patients across objective distances. Distances walked with a WCD-guided walk test were consistent whether conducted in the clinic or at home and were reliable over time. Correspondence: Ashley E. Burch, PhD, Department of Psychology, East Carolina University, 104 Rawl Bldg, Greenville, NC 27858 (burchas15@ecu.edu). Ashley E. Burch, PhD: research grants: Medtronic, ZOLL Medical. All funds are directed to East Carolina University. Andreas J. Rieth, MD: research grants: Pfizer, directed to Kerckhoff-Klinik Forschungs GmbH; Biotest, directed to Kerckhoff Herzforschungsinstitut; speaker fees and/or honoraria: St Jude Medical, Actelion, Novartis, and Orion Pharma. Nicole R. Bianco, PhD, Employee, ZOLL Medical. Samuel F. Sears, PhD: honoraria/consulting fees: Medtronic, Boston Scientific, St Jude Medical, ZOLL Medical; research grants: Medtronic, ZOLL Medical. All funds are directed to East Carolina University. The rest of 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.

Interval Endurance and Resistance Training as Part of a Community-Based Secondary Prevention Program for Patients With Diabetes Mellitus and Coronary Artery Disease Purpose: High-intensity interval training (HIIT) has been observed to improve health and fitness in patients with cardiovascular disease. High-intensity interval training may not be appropriate in community-based settings. Moderate-intensity interval training (MIIT) and resistance training (RT) are emerging as effective alternatives to HIIT. These have not been well investigated in a community-based cardiac maintenance program. Methods: Patients with coronary artery disease and/or diabetes mellitus participated in clinical examinations and a 6-mo exercise program. Center-based MIIT and home-based moderate continuous intensity exercise were performed for 3-5 d/wk for 30-40 min/session. RT, nutritional counseling, coping, and behavioral change strategies were offered to all patients. Within-group changes in clinical metrics and exercise performance were assessed on a per-protocol basis after 6 mo. Results: Two hundred ninety-two patients (74%) concluded the 6-mo program. There were no serious adverse events. The peak oxygen uptake and peak workload increased significantly, 21.8 ± 6.1 to 22.8 ± 6.3 mL/kg/min and 128 ± 39 to 138 ± 43 W, respectively (both P < .001). Submaximal exercise performance increased from 68 ± 19 to 73 ± 22 W (P < .001). Glycated hemoglobin decreased from 6.57 ± 0.93% to 6.43 ± 0.12%, (P = .023). Daily injected insulin dosage was reduced from 42 IU (interquartile range: 19.0, 60.0) to 26 IU (interquartile range: 0, 40.3, P < .001). Conclusions: MIIT and RT were feasible and effective in a community-based cardiac maintenance program for patients with cardiovascular disease, improving exercise performance, and blood glucose control. Correspondence: Jeffrey W. Christle, PhD, Division of Cardiovascular Medicine, Department of Medicine, Stanford University, Falk Cardiovascular Research Building, 870 Quarry Road Ext, Palo Alto, CA 94304 (christle@stanford.edu). The authors declare no conflicts of interest. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Effects of a Cardiac Rehabilitation Program Versus Usual Care on Cardiopulmonary Function in Patients With Cardiac Syndrome X Purpose: Because of uncertainty in the pathophysiological process, the treatment of cardiac syndrome X (CSX) is still under study. Addressing the effects of cardiac rehabilitation (CR) can help promote the prescription of this modality as an adjuvant therapy for these patients. Methods: This study was performed on 30 patients with effort-induced angina pectoris using a positive exercise test and/or myocardial perfusion scan in the absence of obvious stenosis or a stenosis of <50% on coronary angiography. The patients were divided into the CR and usual care (UC) groups and underwent cardiopulmonary exercise testing with gas exchange analysis before and after the study. The Duke Treadmill Score was used to compare prognosis and survival estimates of patients. Results: An increase in peak oxygen uptake (Vo2) was significantly higher in the CR group than in the control group (P = .017). Resting Vo2 was also increased in the CR group, but its difference with the UC group was not statistically significant. Resting O2 pulse was increased in the CR group, which significantly differed between groups (P = .041). Exercise test duration and the Duke Treadmill Score significantly increased in the CR group as compared with the UC group (P = .003 and P = .002, respectively). Also, recovery heart rate in the first minute was significantly improved in CR group. Conclusion: Adding a 4-wk course of CR to UC for patients with CSX not only increased the Duke Treadmill Score and exercise test duration but also improved the resting O2 pulse, peak Vo2, and first-minute recovery heart rate. Correspondence: Reza Mazaheri, MD, Sports Medicine Research Center, Tehran University of Medical Sciences, Imam Khomeini Hospital Complex, Tehran, Iran 1419733141 (mazaheri_md@tums.ac.ir). The authors declare no conflicts of interest. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.

Changes in Physical Performance and Their Association With Health-Related Quality of Life in a Mixed Nonischemic Cardiac Population That Participates in Rehabilitation Purpose: Exercise-based cardiac rehabilitation improves physical performance and health-related quality of life (HRQoL). However, whether improvements in physical performance are associated with changes in HRQoL has not been adequately investigated in a nonischemic cardiac population. Methods: Patients who were ablated for atrial fibrillation, who underwent heart valve surgery or who were treated for infective endocarditis, and who participated in 1 of 3 randomized controlled rehabilitation trials were eligible for the current study. Change in physical performance and HRQoL were measured before and after a 12-wk exercise intervention. Physical performance was assessed using a cardiopulmonary exercise test, a 6-min walk test, and a sit-to-stand test. Health-related quality of life was assessed using the generic 36-Item Short Form Health Survey and the disease-specific HeartQoL questionnaire. Spearman correlation coefficient (ρ) and linear regressions quantified the association between changes in physical outcome measures and changes in HRQoL. Results: A total of 344 patients were included (mean age: 60.8 ± 11.6 yr and 77% males). Associations between changes in physical outcome measures and HRQoL ranged from very weak to weak (ρ = −0.056 to 0.228). The observed associations were more dominant within physical dimensions of the HRQoL compared with mental or emotional dimensions. After adjusting for sex, age, and diagnosis, changes in physical performance explained no more than 20% of the variation in the HRQoL. Conclusion: The findings show that the positive improvement in HRQoL from exercise-based cardiac rehabilitation cannot simply be explained by an improvement in physical performance. Correspondence: Lars Hermann Tang, PhD, National Centre for Rehabilitation and Palliative Care, University of Southern Denmark and Odense University Hospital, Vestergade 17, DK-5800, Nyborg, Denmark (Lars.hermann.tang@rsyd.dk). The authors declare no conflicts of interest. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.