HIIT Improves Survival of Heart Failure Patients

Study Overview
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Brief Summary
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BACKGROUND Global burdens of heart failure (HF) are increasing in modern societies. High-intensity interval training (HIIT) increases peak oxygen consumption (VO2peak) in HF patients, which was hypothesized to improve the survival of HF patients. OBJECTIVES The cohort study aimed to highlight the effect of HIIT on long-term survivals of HF patients. METHODS 329 HF patients, enrolled between 2009 and 2016, received multidisciplinary disease management program (MDP). They had cardiopulmonary exercise test for peak exercise capacity (VO2peak), echocardiographic examination for left ventricular ejection fraction (LVEF), LV end-diastolic diameter (LVEDD), and LV end-systolic diameter (LVESD), b-type natriuretic peptide (BNP), and quality of life questionnaire. HF patients with LVEF≤ 40% (HFrEF) and HF patients with LVEF> 40% (HFpEF) underwent≥ 36 times of HIIT. HFrEF and HFpEF patients were classified as the MDP group. Generalized estimating equation (GEE) was used to estimate the interaction between time and VO2peak, LVEF, LVEDD, LVESD, and BNP during the follow-up. Survival analysis was conducted to assess effects of HIIT on the long-term survival of HF during at end of the study.

Official Title
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Impacts of High-intensity Interval Training on Long-term Survival of Heart Failure Patients

Conditions
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Heart Failure, Cardiac Rehabilitation, Cardiac Remodeling, Ventricular

Intervention / Treatment
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* Behavioral: High-intensity interval training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: From January 1st, 2009 to December 31st, 2016, HF patients, defined according to the European society of cardiology, with stable clinical status greater than 4 weeks after optimal treatment were enrolled in the study. Exclusion Criteria: Those, who were ≥ 80 years and < 20 years, unable to perform exercise caused by other non-cardiac disease, pregnant, future cardiac transplantation within 6 months, uncompensated HF patients, pacemaker patients, and renal patients with estimated glomerular filtration rate < 30 ml/min/1.73m2, were not candidates in the study. Patients had absolute contraindications for cardiopulmonary exercise test (CPET) and aerobic activities, suggested by the American College of Sports Medicine (ACSM), were also excluded in the study.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| HIIT subjects in HFrEF patients<br>heart failure patients with reduced ejection fraction (HFrEF) received at least 36 times of high-intensity interval training (HIIT) | Behavioral: High-intensity interval training<br>* Patients warmed up for 3 min at 30% of peak oxygen consumption (VO2peak). Five 3-minute intervals at 80% of VO2peak and each interval was separated by 3-minute exercise at 40% of VO2peak. The exercise session was terminated by 3-minute cool-down at 30% of VO2peak. All subjects used a EKG and BP monitors as indicators of the assigned exercise intensity. Borg 6-to-20 scale was used to assess the rate of perceived exertion during and after each exercise session. Patients suffering unstable hemodynamic, ischemic cardiac symptoms/signs, and uncontrolled arrhythmia were instructed to immediately terminate exercise training.<br>|
| MDP subjects in HFrEF patients<br>heart failure patients with reduced ejection fraction (HFrEF) received only multidisciplinary disease management program (MDP) and underwent less than 36 times of high-intensity interval training (HIIT) or no exercise training | Behavioral: High-intensity interval training<br>* Patients warmed up for 3 min at 30% of peak oxygen consumption (VO2peak). Five 3-minute intervals at 80% of VO2peak and each interval was separated by 3-minute exercise at 40% of VO2peak. The exercise session was terminated by 3-minute cool-down at 30% of VO2peak. All subjects used a EKG and BP monitors as indicators of the assigned exercise intensity. Borg 6-to-20 scale was used to assess the rate of perceived exertion during and after each exercise session. Patients suffering unstable hemodynamic, ischemic cardiac symptoms/signs, and uncontrolled arrhythmia were instructed to immediately terminate exercise training.<br>|
| HIIT subjects in HFpEF patients<br>heart failure patients with preserved ejection fraction (HFpEF) received at least 36 times of high-intensity interval training (HIIT) | Behavioral: High-intensity interval training<br>* Patients warmed up for 3 min at 30% of peak oxygen consumption (VO2peak). Five 3-minute intervals at 80% of VO2peak and each interval was separated by 3-minute exercise at 40% of VO2peak. The exercise session was terminated by 3-minute cool-down at 30% of VO2peak. All subjects used a EKG and BP monitors as indicators of the assigned exercise intensity. Borg 6-to-20 scale was used to assess the rate of perceived exertion during and after each exercise session. Patients suffering unstable hemodynamic, ischemic cardiac symptoms/signs, and uncontrolled arrhythmia were instructed to immediately terminate exercise training.<br>|
| MDP subjects in HFpEF patients<br>heart failure patients with preserved ejection fraction (HFpEF) received only multidisciplinary disease management program (MDP) and underwent less than 36 times of high-intensity interval training (HIIT) or no exercise training | Behavioral: High-intensity interval training<br>* Patients warmed up for 3 min at 30% of peak oxygen consumption (VO2peak). Five 3-minute intervals at 80% of VO2peak and each interval was separated by 3-minute exercise at 40% of VO2peak. The exercise session was terminated by 3-minute cool-down at 30% of VO2peak. All subjects used a EKG and BP monitors as indicators of the assigned exercise intensity. Borg 6-to-20 scale was used to assess the rate of perceived exertion during and after each exercise session. Patients suffering unstable hemodynamic, ischemic cardiac symptoms/signs, and uncontrolled arrhythmia were instructed to immediately terminate exercise training.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| all-cause death | Any mortality during the study period | 2009/1/1 to 2016/12/31 | 
| all-cause re-admission | Any re-admission during the study period | 2009/1/1 to 2016/12/31 |