Different outcomes of a cardiac rehabilitation programme in functional parameters among myocardial infarction survivors according to ejection fraction. Neth Heart J. 2019;27:347-353. [PMID: 30977040 PMCID: PMC6639836 DOI: 10.1007/s12471-019-1269-7]

Effect of Cardiac Rehabilitation on Cardiorespiratory Fitness in Patients With Acute Myocardial Infarction: Role of Diabetes Mellitus and Glycated Hemoglobin Level

PURPOSE

Following acute myocardial infarction (AMI), patients with diabetes mellitus (DM) have a poorer prognosis than those without DM. This study aimed to investigate the benefit of cardiac rehabilitation on cardiorespiratory fitness in patients with AMI, examining whether this effect varied depending on DM and glycated hemoglobin (HbA1c) levels.

METHODS

Data were collected from the medical records of 324 patients diagnosed with AMI who were subsequently referred to participate in a supervised exercise-based cardiac rehabilitation program. Cardiorespiratory fitness was assessed using cardiopulmonary exercise testing before and at 3 and 6 mo after the start of cardiac rehabilitation. Linear mixed models were used to evaluate changes in cardiorespiratory fitness between patients with and without DM during the follow-up period.

RESULTS

In total, 106 patients (33%) had DM. Both patients with and without DM showed a significant improvement in cardiorespiratory fitness from baseline to the 6-mo follow-up. However, the improvement was significantly lower in patients with DM than in those without DM (1.9 ± 1.5 vs. 3.7 ± 3.2 mL/kg/min, P < .001). Among patients with DM, those with HbA1c levels < 7% showed a greater improvement in cardiorespiratory fitness than those with HbA1c ≥ 7% (2.7 ± 1.5 vs. 1.1 ± 1.8 mL/kg/min, P < .001) during the follow-up period.

CONCLUSIONS

Improvements in cardiorespiratory fitness following cardiac rehabilitation were significantly lower in patients with AMI and DM. The response to cardiac rehabilitation in patients is influenced by HbA1c levels. These findings suggest potential implications for individualizing cardiac rehabilitation programming and ensuring optimal glycemic control in patients with AMI and DM.

Current role and future perspectives of cardiac rehabilitation in coronary heart disease

Ischaemic heart disease (IHD) is a major cause of morbidity and mortality worldwide. While there have been major advances in this field, these patients are still a higher risk subgroup. As such, strategies to mitigate risk and tailor secondary prevention measures are of the utmost relevance. Cardiac rehabilitation (CR), encompassing several domains including exercise training, cardiovascular risk factor optimization, nutritional and psychological assessments, as well as other ancillary interventions has shown to be one of the pillars in the contemporary management of patients with IHD. Indeed, CR is associated with several benefits in this population, ranging from functional capacity to improvements in outcomes. Whilst this, there are still several issues concerning the optimal application of CR which are still not fully ascertained, such as lack of referral and completion, as well as questions related to programme design (particularly among patients with multiple comorbidities). In this review, we aim at presenting a pragmatic overview on the current role of CR in the management of individuals with IHD, while also discussing some of the caveats in the current data, as well as future concepts which could help improve the uptake and personalization of this pivotal time-tested intervention.

Suboptimal control of cardiovascular risk factors in myocardial infarction survivors in a cardiac rehabilitation program

INTRODUCTION AND OBJECTIVES

As short-term mortality continues to decrease after myocardial infarction (MI), secondary prevention strategies attain increasing relevance. This study aimed at assessing the control of cardiovascular (CV) risk factors, including dyslipidemia, hypertension and diabetes, in a contemporary cohort of MI survivors who completed an exercise-based cardiac rehabilitation (EBCR) program.

METHODS

Observational, retrospective cohort study including patients admitted to a tertiary center with acute MI between November 2012 and April 2017, who completed a phase II EBCR program after discharge. Achievement of low-density lipoprotein (LD) cholesterol, blood pressure and HbA1c guideline recommended targets was assessed. Lipid profile parameters were assessed and compared at three time points (hospitalization, beginning and end of the program).

RESULTS

A total of 379 patients were included. Mean age was 58.8±10.6 years; 81% were male. Considering the European Society of Cardiology's guidelines on contemporary data collection, 61%, 87% and 71% achieved the recommended LDL cholesterol, blood pressure and HbA1c targets, respectively, at the end of the program. Combining all three risk factors, 42% achieved the recommended targets. High-sensitivity C-reactive protein decreased between the beginning and the end of the program [0.14 (0.08-0.29) mg/L to 0.12 (0.06-0.26) mg/L; p<0.001].

CONCLUSION

Despite contemporary management strategies, including enrollment in a structured EBCR program, a substantial number of patients presented suboptimal control of CV risk factors. Considering the dyslipidemia, hypertension and diabetes results, less than half of the enrolled individuals achieved the recommended targets. These findings highlight a pivotal unmet need which could be particularly relevant in improving CV outcomes by enhancing secondary prevention profiles.

Suppression of tumorigenicity 2 after exercise: a systematic review

Exercise is a pivotal physiological activity, associated with benefits. Whilst the importance of physical activity is consensual along different steps of the cardiovascular (CV) continuum, there has been interest in assessing the CV adaptations to vigorous exercise. Indeed, exercise can be associated with increases in cardiac biomarkers, though the scope of this observation remains elusive. Interleukin 1 receptor related protein, Suppression of tumorigenicity 2 (ST2) is a biomarker related to the pathophysiology of fibrosis, having shown promise in the study of heart failure. Knowledge of ST2 kinetics could improve understanding of the mechanistic pathways related to CV adaptations to exercise. To assess the current state-of-the-art concerning ST2 levels after exercise in healthy individuals. A systematic review was carried out on three databases (Pubmed, ISI Web of Science and Scopus), up to October 2020, using the queries "ST2" or "ST-2" + "exercise" or "running". A total of six studies were included in the review, encompassing 349 subjects (73% male gender) in which ST2 was assessed. Most studies reported increases in ST2 levels after exercise. Three studies, encompassing a total of 219 individuals, described a cut-off level of 35 ng/dL for ST2. In these, 92.7% of subjects had ST2 levels above this cut-off after exercise (running in all studies). Most studies report increased levels of ST2 after exercise, with an important number of individuals exceeding the 35 ng/dL threshold. Given the small number of individuals represented and the lack of imaging data and long-term follow-up, further prospective larger studies should target this.

Effect of exercise training on left ventricular remodeling in patients with myocardial infarction and possible mechanisms

BACKGROUND

A growing amount of evidence provides support for the hypothesis that acute myocardial infarction (AMI) patients should go through cardiopulmonary exercise testing (CPET) about 3-5 d after AMI is diagnosed, make reasonable exercising prescription, and conduct exercise training under guidance.

AIM

To investigate the effect of exercise training (ET) on left ventricular systolic function and left ventricular remodeling (LVRM) and to study the possible mechanisms of LVRM by the changes of matrix metallopeptidase 9 (MMP-9) and tissue inhibitor of metalloproteinases 1 (TIMP-1) in patients with acute ST-segment elevation myocardial infarction (STEMI).

METHODS

Sixty patients with first STEMI undergoing direct percutaneous coronary intervention from February 2008 to October 2008 were randomly assigned to an exercise group (n = 30) and a control group (n = 30). The levels of MMP-9 and TIMP-1 were measured in all patients at 1 d, 10-14 d, 30 d, and 6 mo after admission. Two-dimensional echocardiography and cardiopulmonary exercise testing were done in patients at 10-14 d and 6 mo after admission.

RESULTS

There was no significant difference in CPET at baseline between the exercise group and the control group. At 6 mo, the time of exercise, peak and anaerobic threshold values of O₂ uptake, and metabolic equivalents increased in both groups, but markedly increased in the exercise group. At baseline, there were no significant differences in left ventricular ejection fraction (LVEF) between the two groups. At 6 mo, LVEF increased in the exercise group, but not in the control group. At 6 mo, the percentage of patients with positive result of LVRM was 26.6% in the exercise group and 52.6% in the control group (P < 0.05). The levels of plasma MMP-9 and TIMP-1 and the ratio of MMP-9 to TIMP-1 in both groups had no significant difference at 1 d and 10-14 d after AMI, but at 30 d and 6 mo, the levels of plasma MMP-9 and TIMP-1 in the exercise group were significantly lower than those in the control group; the ratio of MMP-9 to TIMP-1 in the exercise group was significantly higher than that in the control group.

CONCLUSION

ET under supervision based on home condition in early and recovery stage of AMI can improve exercise cardiopulmonary function and prevent the LVRM. Therefore, it may reduce unfavorable remodeling response by decreasing the levels of plasma MMP-9 and TIMP-1 and adjusting the ratio of MMP-9 to TIMP-1 hereafter.

Cardiac Rehabilitation and Physical Performance in Patients after Myocardial Infarction: Preliminary Research

(1) Background: Cardiovascular diseases, in particular, myocardial infarction (MI), are the main threats to human health in modern times. Cardiac rehabilitation (CR), and especially increased physical activity, significantly prevent the consequences of MI. The aim of this study was to assess physical performance in patients after MI before and after CR. (2) Methods: 126 patients after MI were examined. They were admitted to the cardiac rehabilitation ward twice: in the 3rd month after MI, and then in the 6th month after the last rehabilitation session. CR lasted 20 treatment days (4 weeks with 5 treatment days and 2 days’ break). The exercise stress test on the treadmill and a 6-minute walk test (6MWT) were used to assess physical performance. Patients were assigned to an appropriate rehabilitation model due to their health condition. (3) Results: In the studied group, the exercise stress test time and the metabolic equivalent of task (MET), the maximal oxygen consumption (VO2max), and 6MWT score increased significantly (p = 0.0001) at two time-points of observation. (4) Conclusion: CR significantly improves physical performance in patients after MI.

Differential impact of a cardiac rehabilitation program in functional parameters according to patient gender

INTRODUCTION

Exercise-based cardiac rehabilitation (EBCR) programs are of paramount importance in the management of acute myocardial infarction (AMI) survivors. Albeit this, female patients tend to be less referred for these programs, while also having a poorer prognosis. We aimed at assessing the impact of a contemporary EBCR program on functional parameters after an AMI, and specifically the impact of gender on its potential benefits.

METHODS

Observational, retrospective cohort study including all patients admitted to a tertiary center due to an AMI who completed a phase II EBCR program after discharge, between November 2012 and April 2017. Functional parameters were assessed by a symptom-limited cardiopulmonary exercise test (CPET). Patients were dichotomized according to gender.

RESULTS

A total of 379 patients were included, 19% of whom were women. After the program, peak oxygen uptake (pVO2) and exercise duration increased significantly (P<0.001). Though female patients presented a lower pVO2 and completed a shorter CPET at both the beginning and end of the study, there were no differences in the magnitude of improvement in these parameters between both groups [pVO2 delta 1.37 ± 3.08 vs 1.31 ± 2.62 mL/kg/min, P=0.876; CPET duration delta 120 (60-167) vs 85 (60-146), P=0.176].

CONCLUSIONS

A contemporary EBCR program was associated with significant improvements in functional parameters, as assessed by CPET. Though female patients had lower levels of pVO2, the benefits of this program were similar among groups. These results highlight the importance of EBCR among this higher risk subset of patients.

Using Biosensors and Digital Biomarkers to Assess Response to Cardiac Rehabilitation: Observational Study

BACKGROUND

Cardiac rehabilitation (CR) is known for its beneficial effects on functional capacity and is a key component within current cardiovascular disease management strategies. In addition, a larger increase in functional capacity is accompanied by better clinical outcomes. However, not all patients respond in a similar way to CR. Therefore, a patient-tailored approach to CR could open up the possibility to achieve an optimal increase in functional capacity in every patient. Before treatment can be optimized, the differences in response of patients in terms of cardiac adaptation to exercise should first be understood. In addition, digital biomarkers to steer CR need to be identified.

OBJECTIVE

The aim of the study was to investigate the difference in cardiac response between patients characterized by a clear improvement in functional capacity and patients showing only a minor improvement following CR therapy.

METHODS

A total of 129 patients in CR performed a 6-minute walking test (6MWT) at baseline and during four consecutive short-term follow-up tests while being equipped with a wearable electrocardiogram (ECG) device. The 6MWTs were used to evaluate functional capacity. Patients were divided into high- and low-response groups, based on the improvement in functional capacity during the CR program. Commonly used heart rate parameters and cardiac digital biomarkers representative of the heart rate behavior during the 6MWT and their evolution over time were investigated.

RESULTS

All participating patients improved in functional capacity throughout the CR program (P<.001). The heart rate parameters, which are commonly used in practice, evolved differently for both groups throughout CR. The peak heart rate (HRpeak) from patients in the high-response group increased significantly throughout CR, while no change was observed in the low-response group (F4,92=8.321, P<.001). Similar results were obtained for the recovery heart rate (HRrec) values, which increased significantly over time during every minute of recuperation, for the high-response group (HRrec1: P<.001, HRrec2: P<.001, HRrec3: P<.001, HRrec4: P<.001, and HRrec5: P=.02). The other digital biomarkers showed that the evolution of heart rate behavior during a standardized activity test differed throughout CR between both groups. These digital biomarkers, derived from the continuous measurements, contribute to more in-depth insight into the progression of patients' cardiac responses.

CONCLUSIONS

This study showed that when using wearable sensor technology, the differences in response of patients to CR can be characterized by means of commonly used heart rate parameters and digital biomarkers that are representative of cardiac response to exercise. These digital biomarkers, derived by innovative analysis techniques, allow for more in-depth insights into the cardiac response of cardiac patients during standardized activity. These results open up the possibility to optimized and more patient-tailored treatment strategies and to potentially improve CR outcome.

Differential Impact of a Cardiac Rehabilitation Program on Functional Parameters in Elderly versus Non-Elderly Myocardial Infarction Survivors

BACKGROUND

Exercise-based cardiac rehabilitation (EBCR) plays a pivotal role in the management of acute myocardial infarction (AMI). Studies have shown that older individuals have a worse prognosis after an AMI, attesting to the importance of risk reduction strategies. We aimed at assessing the impact of age (patients dichotomized as ≥65 years old or <65 years old) on the functional benefits of an EBCR program among AMI survivors.

DESIGN

Observational, retrospective cohort study.

PARTICIPANTS

All patients admitted due to an AMI who completed a phase II EBCR program after discharge, between November 2012 and April 2017.

INTERVENTION

EBCR program.

MEASUREMENTS

Functional parameters were assessed by a symptom-limited cardiopulmonary exercise test.

RESULTS

A total of 379 patients were included (30% aged ≥65 years). After the EBCR program, peak oxygen uptake (pVO2) and exercise duration increased significantly. Patients aged ≥65 years presented with more comorbidities and a lower functional capacity. Those aged ≥65 years presented significantly smaller improvements in pVO2 (0.79 ± 2.61 vs. 1.60 ± 3.11 mL/kg/min, p = 0.016) and exercise duration [75 (59-120) vs. 120 s (60-180), p = 0.002]. This was maintained after adjusting for several potential confounders.

CONCLUSION

Older patients have a worse functional capacity than their younger counterparts. Still, a contemporary EBCR program was associated with significant functional improvements among those aged ≥65 years. The smaller improvements even after adjustments for potential confounders suggest that physiological differences may contribute to this finding. These results highlight the relevance of EBCR among this higher-risk subgroup.