Effects of 6 Months of Exercise-Based Cardiac Rehabilitation on Autonomic Function and Neuro-Cardiovascular Stress Reactivity in Coronary Artery Disease Patients

The psychological well-being index and quality of life after a cardiac rehabilitation program based on aerobic training and psychosocial support

BACKGROUND

This study aimed to investigate the physical and psychological benefits of an alternative cardiac rehabilitation program based on therapeutic groups during physical exercise sessions and to compare the results with those of a conventional cardiac rehabilitation program.

METHOD

The sample included 112 patients from the cardiac rehabilitation unit of a medical center, 91.1 % of whom were male. The control group consisted of 47 subjects, with a mean age of 57.89 ± 12.30 and the experimental group consisted of 65 subjects, with a mean age of M = 58.38 ± 9.86. Quality of life, psychological well-being, health-related quality of life, body mass index, blood pressure, abdominal circumference and resting heart rate were measured before starting and at the end of the cardiac rehabilitation program.

RESULTS

The experimental group improved significantly more than the control group in body mass index, systolic and diastolic blood pressure, abdominal circumference, and resting heart rate (p value < 0.005). In addition, the experimental group had significantly greater improvements in quality of life, psychological well-being, and health-related quality of life than the control group (p-value < 0.001).

CONCLUSIONS

A cardiac rehabilitation program based on simultaneous aerobic training and psychosocial support improved the physical function, health-related quality of life and well-being.

Exercise Attenuates Myocardial Ischemia-Reperfusion Injury by Regulating Endoplasmic Reticulum Stress and Mitophagy Through M2 Acetylcholine Receptor

Aims: Adaptive changes in the heart by exercise have been shown to reduce the risk of cardiovascular disease, and M2 Acetylcholine receptor (M2AChR), a receptor abundantly present on cardiac parasympathetic nerves, is closely associated with the development of cardiovascular disease. The present study intends to investigate whether exercise can regulate endoplasmic reticulum stress (ERS) and mitophagy through M2AChR to resist myocardial ischemia-reperfusion (I/R) injury and to elucidate its mechanism of action. Results: Exercise enhanced parasympathetic nerve function and increased myocardial M2AChR protein expression in I/R rats. In addition, it promoted the protein expression of MFN2 and inhibited the expression of Drp1, Chop, PINK1/Parkin, and PERK/eIF2α/ATF4 signaling pathways, effectively reducing mitophagy, ERS, and apoptosis. At the cellular level, 5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR) reduced hypoxia/reoxygenation (H/R)-induced ERS through the downregulated expression of PERK/eIF2α/ATF4 pathway proteins in H9C2 cardiomyocytes. When intervened with M2AChR inhibitors, the levels of ERS and phosphorylation levels of the PERK/eIF2α/ATF4 pathway were increased in H/R cells. Innovation and Conclusion: Exercise intervention activated the parasympathetic state in rats. It inhibited myocardial mitophagy and ERS levels, and reduced myocardial apoptosis through M2AChR, thereby resisting I/R-induced myocardial injury and improving cardiac function. Antioxid. Redox Signal. 40, 209-221.

CVRanalysis: a free software for analyzing cardiac, vascular and respiratory interactions

Introduction: Simultaneous beat-to-beat R-R intervals, blood pressure and respiration signals are routinely analyzed for the evaluation of autonomic cardiovascular and cardiorespiratory regulations for research or clinical purposes. The more recognized analyses are i) heart rate variability and cardiac coherence, which provides an evaluation of autonomic nervous system activity and more particularly parasympathetic and sympathetic autonomic arms; ii) blood pressure variability which is mainly linked to sympathetic modulation and myogenic vascular function; iii) baroreflex sensitivity; iv) time-frequency analyses to identify fast modifications of autonomic activity; and more recently, v) time and frequency domain Granger causality analyses were introduced for assessing bidirectional causal links between each considered signal, thus allowing the scrutiny of many physiological regulatory mechanisms. Methods: These analyses are commonly applied in various populations and conditions, including mortality and morbidity predictions, cardiac and respiratory rehabilitation, training and overtraining, diabetes, autonomic status of newborns, anesthesia, or neurophysiological studies. Results: We developed CVRanalysis, a free software to analyze cardiac, vascular and respiratory interactions, with a friendly graphical interface designed to meet laboratory requirements. The main strength of CVRanalysis resides in its wide scope of applications: recordings can arise from beat-to-beat preprocessed data (R-R, systolic, diastolic and mean blood pressure, respiration) or raw data (ECG, continuous blood pressure and respiratory waveforms). It has several tools for beat detection and correction, as well as setting of specific areas or events. In addition to the wide possibility of analyses cited above, the interface is also designed for easy study of large cohorts, including batch mode signal processing to avoid running repetitive operations. Results are displayed as figures or saved in text files that are easily employable in statistical softwares. Conclusion: CVRanalysis is freely available at this website: anslabtools.univ-st-etienne.fr. It has been developed using MATLAB® and works on Windows 64-bit operating systems. The software is a standalone application avoiding to have programming skills and to install MATLAB. The aims of this paper area are to describe the physiological, research and clinical contexts of CVRanalysis, to introduce the methodological approach of the different techniques used, and to show an overview of the software with the aid of screenshots.

The effect of cardiac rehabilitation on cardiopulmonary function after coronary artery bypass grafting: A systematic review and meta-analysis

We carried out a meta-analysis on the effect of cardiac rehabilitation (CR) on cardiopulmonary function after coronary artery bypass grafting (CABG). Four databases were searched for studies comparing CR with control. A random-effects model was used to pool mean difference (MD). The meta-analysis showed an increase in peak oxygen consumption (peak VO2) (MD = 1.93 mL/kg/min, p = 0.0006), and 6-min walk distance (6MWD) (MD = 59.21 m, p < 0.00001), and a decrease in resting heart rate (resting HR) (MD = 5.68 bpm, p < 0.0001) in the CR group. The subgroup analysis revealed aerobic exercise could further improve resting HR and peak HR, and physical/combination with aerobic exercise could further increase 6MWD. The improvement of peak VO2, workload, resting HR, peak HR, and 6MWD regarding CR performed within one week after CABG is greater than that one week after CABG. CR after CABG can improve the cardiopulmonary function, which is reflected by the improvement of peak VO2, 6MWD, and resting HR.

Aging is associated with enhanced central, but impaired peripheral arms of the sympathetic baroreflex arc

We tested the hypothesis that the baroreflex control of action potential (AP) subpopulations would be blunted in older compared to young adults. Integrated muscle sympathetic nerve activity (MSNA) and the underlying sympathetic APs were obtained using microneurography and a continuous wavelet analysis approach, respectively, during 5 minutes of supine rest in 13 older (45-75 years, 6 females) and 14 young (21-30 years, 7 females) adults. Baroreflex threshold relationships were quantified as the slope of the linear regression between MSNA burst probability (%) and diastolic blood pressure (mmHg), or AP cluster firing probability (%) and diastolic blood pressure (mmHg). Integrated MSNA baroreflex threshold gain was greater in older compared to young adults (older: -7.6±3.6 %/mmHg vs. Young: -3.5±1.5 %/mmHg, P<0.001). Similarly, the baroreflex threshold gain of AP clusters was modified by aging (group-by-cluster effect: P<0.001) such that older adults demonstrated greater baroreflex threshold gains of medium-sized AP clusters (e.g., Cluster 4, older: -8.2±3.2 %/mmHg vs. Young: -3.6±1.9 %/mmHg, P=0.003) but not for the smallest- (Cluster 1, older: -1.6±1.9 %/mmHg vs. Young: -1.0±1.7 %/mmHg, P>0.999) and largest-sized (Cluster 10, older: -0.5±0.5 %/mmHg vs. Young: -0.2±0.1 %/mmHg, P=0.819) AP clusters compared to young adults. In contrast, the peak change in mean arterial pressure (MAP) following a spontaneous MSNA burst (i.e., sympathetic transduction) was impaired with aging (older: -0.7±0.3 mmHg vs. Young: 1.8±1.2 mmHg, P<0.001). We conclude that aging is associated with elevated baroreflex control over high-probability AP content of sympathetic bursts that may compensate for impaired sympathetic neurovascular transduction.

The effect of a home-based coaching program on heart rate variability in subacute stroke patients: a randomized controlled trial

Autonomic imbalance in stroke is characterized by increased sympathetic activity and reduced vagal nerve activity. Physical activity could be a strategy to counteract autonomic control impairments after a stroke. The aim of the study was to evaluate the effect on heart rate variability of a 6-month coaching program in a home setting in subacute stroke patients. Eighty-four stroke patients participated in the study. They were randomly assigned to the experimental group or the control group. The intervention was a coaching program, consisting of physical activity, home visits and a weekly phone call. Patients were evaluated after hospital discharge (T0) and at the end of the 6-month period (T1). Heart rate variability measures were recorded in the supine and orthostatic positions. Time and frequency domain values were treated using Kubios. Distance on 6 minutes walking test (6MWT), Barthel and motricity index and modified functional ambulation categories were evaluated. No effects were found on time and frequency domain values in the supine and orthostatic positions in either group. Walking distance on 6MWT increased significantly between T0 and T1 in experimental group (377 ± 141-448 ± 140 m; P < 0.02) with no effects in control group (373.6 ± 150.6-394.6 ± 176.4 m). No other functional effects were found. A coaching program in a home setting had no effect on heart rate variability, probably due to time of recovery and exercise intensity. Future research is needed to understand the lack of changes in heart rate variability by physical activity in subacute stroke patients.

Effects of resistance added on aerobic training on autonomic function in cardiac patients

OBJECTIVE

Autonomic imbalance in patients with chronic heart failure (CHF) and cardiovascular diseases (CVD) is characterized by reduced parasympathetic and enhanced sympathetic activity. Aerobic exercise improves autonomic function in patients with CHF and CVD. However, little is known about the effects of resistance training (RT) on cardiac autonomic function. Therefore, we aimed to investigate the effects of RT added on aerobic training on autonomic function in patients with CHF and CVD.

DATA SOURCES

The relevant clinical trials were searched in PubMed, Physiotherapy evidence Database (PEDro, Science Direct and Google Scholar databases using the following keywords, "resistance or strength training", "chronic heart failure", "coronary artery disease", "myocardial infarction", "hypertension", "cardiovascular disease", "heart rate variability (HRV)", "heart rate recovery (HRR)", "muscle sympathetic nerve activity (MSNA)", and "autonomic function".

DATA SYNTHESIS

Twelve articles with 323 subjects were eligible to be evaluated. The outcome measures included HRV, HRR, and MSNA. There were seven studies on CHF, two on CAD, and three studies on hypertension. Meta-analysis of all the studies showed that combined RT and aerobic training decreased MSNA significantly in patients with CHF and CAD (mean difference: -3.796; CI: -6.779 to 0.813; p=0.013; I2 =93.5%). No study evaluated the effects of RT or combined training on HRR.

CONCLUSION

We could not find sufficient data about the effects of RT alone on HRV and HRR, but the results showed that combined RT and aerobic training improved MSNA in patients with CHF and CAD, significantly. Further studies with similar methodological principles on the same patient population are needed.

Early rehabilitation after acute myocardial infarction: A nationwide inpatient database study

BACKGROUND

The effects and safety of early rehabilitation in intensive care units (ICU) remain unclear for patients after acute myocardial infarction (AMI).

METHODS

Using Japanese Diagnosis Procedure Combination inpatient data between July 2010 and March 2018, we identified 31,603 adult patients with AMI who underwent percutaneous coronary intervention on the day of admission and who were admitted to the ICU for more than three consecutive days. Patients who started a rehabilitation program within three days of ICU admission were included in the early rehabilitation group, while others were included in the usual care group. The primary outcome was activities of daily living (ADL) at discharge, as measured using the Barthel Index score. We conducted inverse probability of treatment weighting analyses.

RESULTS

The data of 31,603 patients were examined, 5,147 of whom were assigned to the early rehabilitation group. In the weighted cohort, the Barthel Index score at discharge was not significantly different between the two groups. The early rehabilitation group had a significantly shorter hospital stay, shorter ICU stay, and lower total hospitalization costs.

CONCLUSIONS

No correlations were observed between early rehabilitation and ADL at discharge. However, the present results suggest that early rehabilitation is safe and associated with lower hospital costs and shorter hospital stays after AMI.

Safety and improvement in exercise tolerance with interval training vs moderate-intensity continuous training in heart disease patient of very high cardiovascular risk

Objetivo:

Evaluar la seguridad y el efecto del entrenamiento por intervalos de moderada y alta intensidad (EIMI, EIAI) y compararlo con el entrenamiento de intensidad moderada continua (EIMC) en pacientes de riesgo cardiovascular (RCV) muy alto.

Método:

Estudio cuasi experimental de 81 pacientes que ingresaron al programas de rehabilitación cardíaca y prevención secundaria (PRHCPS); en la estratificación de riesgo, todos los pacientes presentaron ≥ 2 factores de RCV alto. Entrenamiento concurrente: aeróbico supervisado: 2 semanas de entrenamiento de base de EIMC; luego el grupo EIMC con la misma prescripción, EIMI a 3 intervalos de 3’ al 70 a 80% de FCR con pausas activas de 3’ al 60 a 70% de FCR; EIAI, 3 intervalos de 3’ a 80 a 90% de FCR con pausas activas de 3’ al 70 a 80% de FCR, entrenamiento de fuerza con tres sesiones semanales de ejercicios isotónicos y una de calistenia e intervención multidisciplinaria.

Resultados:

81 pacientes asignados en tres grupos: 61 a EIMC, 13 a EIMI y 7 a EIAI, sin diferencias significativas en las variables epidemiológicas. Hubo ganancias porcentuales en MET-carga de 45%, 60% y 86% (p = 0.17) y carga-vatios de 51, 44 y 48 en EIMC, EIMI, EIAI, respectivamente (p = 0.54). A pesar de no existir diferencias estocásticamente significativas intergrupales, sí se registró una ganancia mayor en MET-carga en el grupo de EIAI. No se observó desenlace adverso en ningún tipo de entrenamiento.

Conclusiones:

En cardiópatas de riesgo cardiovascular muy alto, el entrenamiento interválico EIMI/EIAI supervisado es seguro, con tendencia a mayor ganancia en tolerancia al esfuerzo (MET-carga) con el EIAI en comparación con el EIMC.

Effect of Early Rehabilitation on Physical Function in Patients Undergoing Coronary Artery Bypass Grafting: A Nationwide Inpatient Database Study

It is unclear when to begin rehabilitation after coronary artery bypass grafting (CABG) in the intensive care unit (ICU). Using the Japanese Diagnosis Procedure Combination inpatient database from 2010 to 2018, we identified adult patients who underwent a CABG and who were admitted to the ICU for ≥3 consecutive days from the date of their CABG. Patients who started any rehabilitation program prescribed by physicians or therapists within 3 days of CABG were defined as the early rehabilitation group, and the remaining patients were defined as the usual care group. We identified 30,568 eligible patients, with 13,150 (43%) patients in the early rehabilitation group. An inverse probability of treatment weighting analyses showed that the Barthel Index score at discharge in the early rehabilitation group was significantly higher than that in the usual care group (difference: 3.2; 95% confidence interval: 1.5–4.8). The early rehabilitation group had significantly lower in-hospital mortality, total hospitalization costs, length of ICU stay, and hospital stay vs. the usual care group. Our results suggested that early rehabilitation by physicians or therapists beginning within 3 days of CABG was safe, as suggested by the low mortality and improved physical function in patients who underwent CABG.

Cardiometabolic Effects of High-Intensity Hybrid Functional Electrical Stimulation Exercise after Spinal Cord Injury

INTRODUCTION

The prevalence of cardiometabolic disease following spinal cord injury is known to be high. However, it is unknown whether engaging in high-intensity exercise, which is advocated by recent guidelines, is beneficial or feasible for these individuals.

OBJECTIVE

To assess the effects of high-intensity, whole-body exercise on the prevalence of cardiometabolic disease in individuals with spinal cord injury.

DESIGN

Combination of a randomized controlled trial and an open label intervention study of functional electrical stimulation legs plus arms rowing.

SETTING

Outpatient academic rehabilitation hospital.

PARTICIPANTS

Forty individuals with spinal cord injury, with American Spinal Injury Association (ASIA) impairments scales A-D and neurological levels of injury C1-T12.

INTERVENTION

Six months of high-intensity, hybrid-functional electrical stimulation rowing.

MAIN OUTCOME MEASURES

Change in VO_2max , serum lipids, and insulin resistance, prevalence of cardiometabolic disease.

RESULTS

Individuals averaged 42.1 ± 22.0 minutes of hybrid-functional electrical stimulation rowing a week over an average of 1.69 sessions per week over the 6 months of intervention. This amounted to an average of 170.9 ± 100 km rowed, at a mean heart rate of 82.7% of individualized maximum. Only one of 40 individuals met current exercise guidelines for the full 6 months. VO_2max increased significantly (P < .001), yet prevalence of cardiometabolic disease did not change significantly (decrease from 22.5% to 20%, P = .70). Hemoglobin A1c did decrease significantly over this time (P = .01), although serum lipids and fasting glucose/insulin levels were unchanged. In exploratory subanalyses assessing individuals injured ≤12 months, those with more chronic injuries decreased their triglyceride-to-high-density lipoprotein (HDL) ratio (P = .04), a marker of cardiac mortality. Stratifying by neurological level of injury, individuals with paraplegia had worsened low-density lipoprotein (LDL) level (P = .02) and total cholesterol-to-HDL ratio (P = .04) over the 6-month intervention.

CONCLUSIONS

Sustained high-intensity exercise with hybrid functional electrical stimulation rowing does not decrease the prevalence of cardiometabolic disease after spinal cord injury.

Thyroid hormone treatment improved the response to maximum exercise test and preserved the ventricular geometry in myocardial infarcted rats

NEW FINDINGS

What is the central question of this study? Does thyroid hormone treatment given after myocardial infarction preserve left ventricular function and treadmill exercise performance, and improve parameters of oxidative stress in the right ventricle and lungs of Wistar rats? What is the main finding and its importance? Thyroid hormone treatment improved the performance of the maximum exercise test in infarcted rats and induced effects in the heart and lungs that were similar to those observed with exercise training. This suggests there is a significant value of thyroid hormones for preserving exercise tolerance after myocardial infarction.

ABSTRACT

Left ventricular myocardial infarction (MI) provokes damage in the heart and in other tissues, such as right ventricle and lungs. The present study elucidated whether thyroid hormone treatment (THT) may present positive effects in heart and lungs after MI, and whether or not these effects are similar to those of exercise training (ET). Male Wistar rats were divided into four groups: sham operated (SHAM), infarcted (MI), infarcted + exercise training (MIE), and infarcted + thyroid hormones (MIH). A maximum exercise test, left ventricle echocardiography, pulmonary histology, and oxidative stress in the right ventricle and lung were evaluated. THT and ET both reduced left ventricular dilatation and end-diastolic wall stress indexes to a similar extent. MI accentuated the content of macrophages and inflammatory infiltrate in the lungs, which was partially prevented in the MIH and MIE groups. THT and ET presented similar effects in the heart and lungs, and both improved the performance of the maximum exercise test in infarcted animals.

Comparative Effects of High-Intensity Interval Training vs Moderate-Intensity Continuous Training in Phase III of a Tennis-Based Cardiac Rehabilitation Program: A Pilot Randomized Controlled Trial

The aim of the present study was to investigate the effects of two tennis-based cardiac rehabilitation programs using two protocols: high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) in the body composition, physical fitness, heart rate variability, and health-related quality of life. It was performed as a single-blinded randomized controlled trial of 21 people with acute coronary syndrome. The 12-week cardiac rehabilitation program consisted of three sessions per week of 60 min with the main part consisting of 10 sets of 15 s with 15 s of active recovery at 85%–90% of their maximum heart rate or 40 min at 70%–85% of their maximum heart rate in the HIIT and the MICT groups, respectively. Results show that both cardiac rehabilitation programs improved the agility and the mental components of the health-related quality of life (p-value < 0.05). The HIIT protocol also showed a significant improvement in the flexibility of upper and lower limbs (p-value < 0.05). Moreover, significant group × time interaction was found in the handgrip strength in favor of the HIIT group (p-value = 0.035). Nevertheless, no significant effects on cardiorespiratory fitness or heart rate variability were found. Importantly, no adverse event was detected, so HIIT appears to be a safe and effective alternative for the rehabilitation of patients with acute coronary syndrome.

Exercise-based cardiac rehabilitation and parasympathetic function in patients with coronary artery disease: a systematic review and meta-analysis

PURPOSE

The effects of exercise-based cardiac rehabilitation (CR) on parasympathetic modulation are controversial. This systematic review and meta-analysis aims to (a) determine the effect of exercise-based CR on heart-rate-derived indices associated with cardiac parasympathetic modulation in resting and post-exercise conditions in coronary artery disease (CAD) patients and (b) identify the possible moderator variables of the effect of exercise-based CR on parasympathetic modulation.

METHODS

We searched CENTRAL and Web of Science up to November 2018 for the following terms: adult CAD patients, controlled exercise-based CR interventions and parasympathetic modulation measured in resting (vagal-related heart rate variability [HRV] indices of the root mean square of the differences in successive in RR interval [RMSSD] and high frequency [HF]) and post-exercise (heart rate recovery [HRR]) pre- and post-intervention. We estimated a random-effects model of standardised mean difference (SMD) and mean difference (MD) for vagal-related HRV indices and HRR, respectively. We assessed the influence of categorical and continuous variables.

RESULTS

The overall effect size showed significant differences in RMSSD (SMD₊ = 0.30; 95% confidence interval [CI] = 0.12-0.49) and HRR (MD₊ = 5.35; 95% CI = 4.08-6.61 bpm) in favour of the exercise-based CR group. The overall effect size showed no differences in HF between groups (SMD₊ = 0.14; 95% CI,  -0.12-0.40). Heterogeneity analyses reached statistical significance, with high heterogeneity for HF (p < 0.001; I² = 70%) and HRR (p < 0.001; I² = 85%). Analysis of the moderator variables showed that the effect on HRR is greater in young patients (p = 0.008) and patients treated with percutaneous intervention (p = 0.020).

CONCLUSIONS

Exercise-based CR improves the post-exercise parasympathetic function, with greater effects in younger CAD patients and in those who were revascularised with percutaneous intervention. The effects on resting parasympathetic function are more controversial due to methodological inconsistencies in measuring HRV, with the use of RMSSD recommended instead of HF because its results show higher consistency. Future studies involving women, focusing on methodological issues, and performing other training methods are needed to increase our knowledge about this topic.

Effects of 6 Months of Exercise-Based Cardiac Rehabilitation on Autonomic Function and Neuro-Cardiovascular Stress Reactivity in Coronary Artery Disease Patients

Background Autonomic dysregulation represents a hallmark of coronary artery disease (CAD). Therefore, we investigated the effects of exercise-based cardiac rehabilitation (CR) on autonomic function and neuro-cardiovascular stress reactivity in CAD patients. Methods and Results Twenty-two CAD patients (4 women; 62±8 years) were studied before and following 6 months of aerobic- and resistance-training-based CR. Twenty-two similarly aged, healthy individuals (CTRL; 7 women; 62±11 years) served as controls. We measured blood pressure, muscle sympathetic nerve activity, heart rate, heart rate variability (linear and nonlinear), and cardiovagal (sequence method) and sympathetic (linear relationship between burst incidence and diastolic blood pressure) baroreflex sensitivity during supine rest. Furthermore, neuro-cardiovascular reactivity during short-duration static handgrip (20s) at 40% maximal effort was evaluated. Six months of CR lowered resting blood pressure (P<0.05), as well as muscle sympathetic nerve activity burst frequency (48±8 to 39±11 bursts/min; P<0.001) and burst incidence (81±7 to 66±17 bursts/100 heartbeats; P<0.001), to levels that matched CTRL and improved sympathetic baroreflex sensitivity in CAD patients (P<0.01). Heart rate variability (all P>0.05) and cardiovagal baroreflex sensitivity (P=0.11) were unchanged following CR, yet values were not different pre-CR from CTRL (all P>0.05). Furthermore, before CR, CAD patients displayed greater blood pressure and muscle sympathetic nerve activity reactivity to static handgrip versus CTRL (all P<0.05); yet, responses were reduced following CR (all P<0.05) to levels observed in CTRL. Conclusions Six months of exercise-based CR was associated with marked improvement in baseline autonomic function and neuro-cardiovascular stress reactivity in CAD patients, which may play a role in the reduced cardiac risk and improved survival observed in patients following exercise training.