Sustainability of physical work capacity two years post outpatient cardiac rehabilitation.

OBJECTIVE: To determine if supervised training, after the completion of cardiac rehabilitation program, performed for a further two years would help maintain beneficial effects achieved during prolonged outpatient cardiac rehabilitation. DESIGN: Longitudinal parallel-grouped intervention study. SUBJECTS: Patients with coronary artery disease (n = 41, age 59.5 ± 9.3 years), who finished cardiac rehabilitation phase III in our outpatient cardiac rehabilitation facility. INTERVENTION: Two years of supervised exercise training consisting of endurance (either high intensity interval training or pyramid training) and resistance training sessions once a week. MAIN MEASUREMENT: Peak physical work capacity was assessed via an ergometry testing at the beginning and at the end of the study. RESULTS: Comparisons between end-of-cardiac rehabilitation and two years post cardiac rehabilitation revealed maintenance of peak physical work capacity after two years (begin vs end: 170 ± 59 W vs 167 ± 60 W; -0.5 ± 12.8%; p = 0.521). This was independent of exercise training protocols (percent change begin vs end: pyramid: 1.5 ± 11.8%; interval: -1.6 ± 13.4%; p = 0.459). CONCLUSION: Improvement of physical exercise capacity gained during outpatient cardiac rehabilitation can be maintained for up to two years by once-weekly supervised exercise training. Long-term, group-based exercise programs offered at the end of cardiac rehabilitation might be an effective tool to help patients maintain their physical work capacity.

Exercise-induced changes in miRNA expression in coronary artery disease.

OBJECTIVES: Micro ribonucleic acids (miRNAs) are small non-coding RNA molecules that control gene expression by translational inhibition. Exercise has been shown to affect several miRNAs' expression in healthy subjects, but this has not yet been studied in patients with coronary artery disease (CAD). Since exercise training confers beneficial long-term effects and may also trigger acute coronary events, it is of utmost interest to be able to identify those who are risk for untoward effects. Therefore, we set out to assess miRNA expression in response to maximal ergospirometry in patients with CAD. METHODS: Total RNA was extracted from blood drawn immediately before and 5 min after maximal cycle-ergospirometry (10 male and 10 female CAD patients). A qRT-PCR was performed for 187 target miRNAs associated with endothelial function/dysfunction, cardiovascular disease, myocardial infarction, and sudden cardiac death. RESULTS: In response to a maximal ergospirometry, 33 miRNAs significantly changed their expression levels. Of these miRNAs 16 were significantly differently expressed between gender. Using multi-variance analysis, nine miRNAs (let-7e-5p; miR-1; miR-19b-1-5p; miR-103a-3p; miR-148b-3p; miR-181b-5p; miR-188-5p; miR-423-5p; miR-874-3p) showed significantly different responses to maximal ergospirometry between genders. CONCLUSIONS: We report for the first time that in patients with CAD, miRNA expression is amenable to maximal ergospirometry and that the extent of changes differs between genders. Affected by exercise and gender were miRNAs that are associated, among others, with pathways for glucose metabolism, oxidative stress, and angiogenesis. Future studies should assess whether disease-specific miRNA expression in response to maximal exercise might serve as a marker for patient outcome.

Outpatient Cardiac Rehabilitation Closure and Home-Based Exercise Training During the First COVID-19 Lockdown in Austria: A Mixed-Methods Study.

OBJECTIVE: To assess the impact of the closure of group-based cardiac rehabilitation (CR) training during the first COVID-19 lockdown in spring 2020 on patients' physical activity, cardiorespiratory fitness, and cardiovascular risk, and to describe the patient experience of lockdown and home-based exercise training during lockdown. DESIGN: Mixed methods study. Prospectively collected post-lockdown measurements were compared to pre-lockdown medical record data. Quantitative measurements were supplemented with qualitative interviews about the patient experience during lockdown. SETTING: Outpatient CR centre in Salzburg, Austria. PARTICIPANTS: Twenty-seven patients [six female, mean (SD) age 69 (7.4) years] who attended weekly CR training sessions until the first COVID-19 lockdown in March 2020. OUTCOME MEASURES: Quantitative: exercise capacity (maximal ergometer test, submaximal ergometer training), cardiovascular risk (Framingham risk score, blood pressure, body mass index, lipids). Qualitative: individual semi-structured interviews. RESULTS: Exercise capacity had significantly reduced from pre- to post-lockdown: mean (SD) power (W) in maximal ergometry 165 (70) vs. 151 (70), p < 0.001; submaximal ergometer training 99 (40) vs. 97 (40), p = 0.038. There was no significant difference in Framingham risk score and other cardiovascular risk factors. Qualitative data showed that almost all patients had kept physically active during lockdown, but 17 (63%) said they had been unable to maintain their exercise levels, and 15 (56%) felt their cardiorespiratory fitness had deteriorated. Many patients missed the weekly CR training and the motivation and sense of community from training together with others. Several patients stated that without professional supervision they had felt less confident to carry out home-based exercise training at high intensity. CONCLUSION: This study highlights the importance of group-based supervised exercise training for patients who engage well in such a setting, and the detrimental impact of disruption to this type of CR service on physical activity levels and exercise capacity. Additionally, learning from the COVID-19 pandemic may inform the development and implementation of remote CR modalities going forward.

Effect of Different Endurance Training Protocols During Cardiac Rehabilitation on Quality of Life.

BACKGROUND: This study aimed to assess the effect of different types of endurance training during outpatient cardiac rehabilitation on patients' health-related quality of life (HRQL). METHODS: The MacNew Heart Disease HRQL questionnaire and the Hospital Anxiety and Depression Scale were used to assess changes in HRQL in 66 patients before and after 6 weeks of cardiac rehabilitation. Patients were randomized to 1 of 3 types of supervised endurance training: continuous endurance training, high-intensity interval training, and pyramid training. Two-way analysis of variance for repeated measure and chi-square test were used to analyze changes before and after rehabilitation. RESULTS: Attendance rate during the 6 weeks of exercise training was 99.2%. Physical work capacity increased from 136.1 to 165.5 watts (+22.9%; P < .001), and there were no statistical differences between training protocols. Fully completed questionnaires at both time points were available in 46 patients (73.9%; 61.3±11.6 years, 34 males, 12 females). Regardless of the type of supervised endurance training, there was significant improvement during rehabilitation in each of the categories of the MacNew questionnaire (ie, emotion, physical, social, global; all P < .05) and the Hospital Anxiety and Depression Scale (anxiety: P = .05; depression: P = .032), without significant differences between protocols. CONCLUSIONS: All 3 types of endurance training led to significant and well comparable increases in physical work capacity, which was associated with an increase in HRQL independent of the type of training. Our findings support further individualization of training regimes, which could possibly lead to better compliance during life-long home-based exercise training.

Exercise responsive micro ribonucleic acids identify patients with coronary artery disease.

AIMS: Exercise is a trigger for acute coronary events especially in the untrained. Identifying subjects at risk remains a challenge. We set out to assess whether a distinct pattern of micro ribonucleic acids (miRNAs) expressed in response to an acute bout of all-out exercise might exist that would allow discrimination between health and disease. METHODS: Twenty healthy subjects and 20 patients with coronary artery disease (CAD) performed an all-out cycle ergometry. Total RNA was extracted from blood drawn before and after exercise. Each blood sample was analysed for 187 target miRNAs by quantitative reverse transcription polymerase chain reaction. RESULTS: At baseline, 18 miRNAs allowed discrimination between healthy subjects and CAD patients. In response to an acute all-out exercise in healthy subjects 51 miRNAs and in CAD patients 60 miRNAs were significantly modulated (all p < 0.05). Using logistic regression analysis, a unique pattern of pre-exercise miR-150-5p, post-exercise miR-101-3p, miR-141-3p and miR-200b-3p together with maximal oxygen uptake and maximal power corrected for bodyweight allowed discrimination between healthy subjects and CAD patients with an accuracy of 92.5%. CONCLUSION: In this most comprehensive analysis of exercise effects on circulating miRNAs to date we demonstrate for the first time that a distinct combination of miRNAs together with variables of exercise capacity allow robust discrimination between healthy subjects and CAD patients. We postulate that miRNAs may eventually serve as biomarkers to identify patients with CAD and possibly even those at risk of exercise-induced cardiac events.

High-intensity interval training is not superior to other forms of endurance training during cardiac rehabilitation.

BACKGROUND: High-intensity interval training has recently emerged as superior to continuous endurance training in cardiac rehabilitation upon other training regimes. Individually tailored continuous endurance training and pyramid training could induce comparable effects on peak work capacity as high intensity interval training. DESIGN: A prospective, randomized study. METHODS: Effects of the following isocaloric cycle ergometer protocols on peak work capacity have been assessed in patients with coronary artery disease (n = 60) during 6 weeks of outpatient cardiac rehabilitation, i.e. 18 supervised sessions of exercise training: (1) continuous endurance training (n = 20): 33 min at 65-85% peak heart rate; (2) high intensity interval training (n = 20): 4 × 4 min intervals at 85-95% peak heart rate, each followed by 3 min of active recovery at 60-70% peak heart rate; (3) pyramid training (n = 20): 3 × 8 min of stepwise load increase and subsequent decrease from 65-95-65% peak heart rate, supplemented by 2 min recovery at 60-70% peak heart rate between pyramids. All protocols were preceded by 5 min of warm-up and followed by 5 min cool-down at 60-70% peak heart rate. RESULTS: Attendance during exercise sessions was 99.2%. There were significant increases in peak work capacity of comparable magnitude in all three training groups (begin vs. end: continuous endurance training: 136.0 ± 49.6 W vs. 163.4 ± 60.8 W (21.1 ± 8.5%); high-intensity interval training: 141.0 ± 60.4 W vs. 171.1 ± 69.8 W (22.8 ± 6.6%); pyramid training: 128.7 ± 50.6 W vs. 158.5 ± 57.9 W (24.8 ± 10.8%); within groups all p < 0.001; between groups, p = not significant). CONCLUSION: Endurance training protocols assessed in this study all led to significant increases in peak work capacity of comparable magnitude. Our findings suggest that these protocols can be used interchangeably, which will lead to further individualization of exercise prescription and may therefore result in improved adherence to lifelong behavioural changes.