Impact of Exercise-based Cardiac Rehabilitation on In-stent Restenosis with Different Generations of Drug Eluting Stent

Exercise-based cardiac rehabilitation for coronary heart disease

BACKGROUND

Coronary heart disease (CHD) is the most common cause of death globally. However, with falling CHD mortality rates, an increasing number of people living with CHD may need support to manage their symptoms and prognosis. Exercise-based cardiac rehabilitation (CR) aims to improve the health and outcomes of people with CHD. This is an update of a Cochrane Review previously published in 2016.

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of exercise-based CR (exercise training alone or in combination with psychosocial or educational interventions) compared with 'no exercise' control, on mortality, morbidity and health-related quality of life (HRQoL) in people with CHD.

SEARCH METHODS

We updated searches from the previous Cochrane Review, by searching CENTRAL, MEDLINE, Embase, and two other databases in September 2020. We also searched two clinical trials registers in June 2021.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of exercise-based interventions with at least six months' follow-up, compared with 'no exercise' control. The study population comprised adult men and women who have had a myocardial infarction (MI), coronary artery bypass graft (CABG) or percutaneous coronary intervention (PCI), or have angina pectoris, or coronary artery disease.

DATA COLLECTION AND ANALYSIS

We screened all identified references, extracted data and assessed risk of bias according to Cochrane methods. We stratified meta-analysis by duration of follow-up: short-term (6 to 12 months); medium-term (> 12 to 36 months); and long-term ( > 3 years), and used meta-regression to explore potential treatment effect modifiers. We used GRADE for primary outcomes at 6 to 12 months (the most common follow-up time point).  MAIN RESULTS: This review included 85 trials which randomised 23,430 people with CHD. This latest update identified 22 new trials (7795 participants). The population included predominantly post-MI and post-revascularisation patients, with a mean age ranging from 47 to 77 years. In the last decade, the median percentage of women with CHD has increased from 11% to 17%, but females still account for a similarly small percentage of participants recruited overall ( < 15%). Twenty-one of the included trials were performed in low- and middle-income countries (LMICs). Overall trial reporting was poor, although there was evidence of an improvement in quality over the last decade. The median longest follow-up time was 12 months (range 6 months to 19 years). At short-term follow-up (6 to 12 months), exercise-based CR likely results in a slight reduction in all-cause mortality (risk ratio (RR) 0.87, 95% confidence interval (CI) 0.73 to 1.04; 25 trials; moderate certainty evidence), a large reduction in MI (RR 0.72, 95% CI 0.55 to 0.93; 22 trials; number needed to treat for an additional beneficial outcome (NNTB) 75, 95% CI 47 to 298; high certainty evidence), and a large reduction in all-cause hospitalisation (RR 0.58, 95% CI 0.43 to 0.77; 14 trials;  NNTB 12, 95% CI 9 to 21; moderate certainty evidence). Exercise-based CR likely results in little to no difference in risk of cardiovascular mortality (RR 0.88, 95% CI 0.68 to 1.14; 15 trials; moderate certainty evidence), CABG (RR 0.99, 95% CI 0.78 to 1.27; 20 trials; high certainty evidence), and PCI (RR 0.86, 95% CI 0.63 to 1.19; 13 trials; moderate certainty evidence) up to 12 months' follow-up. We are uncertain about the effects of exercise-based CR on cardiovascular hospitalisation, with a wide confidence interval including considerable benefit as well as harm (RR 0.80, 95% CI 0.41 to 1.59; low certainty evidence). There was evidence of substantial heterogeneity across trials for cardiovascular hospitalisations (I2 = 53%), and of small study bias for all-cause hospitalisation, but not for all other outcomes. At medium-term follow-up, although there may be little to no difference in all-cause mortality (RR 0.90, 95% CI 0.80 to 1.02; 15 trials), MI (RR 1.07, 95% CI 0.91 to 1.27; 12 trials), PCI (RR 0.96, 95% CI 0.69 to 1.35; 6 trials), CABG (RR 0.97, 95% CI 0.77 to 1.23; 9 trials), and all-cause hospitalisation (RR 0.92, 95% CI 0.82 to 1.03; 9 trials), a large reduction in cardiovascular mortality was found (RR 0.77, 95% CI 0.63 to 0.93; 5 trials). Evidence is uncertain for difference in risk of cardiovascular hospitalisation (RR 0.92, 95% CI 0.76 to 1.12; 3 trials). At long-term follow-up, although there may be little to no difference in all-cause mortality (RR 0.91, 95% CI 0.75 to 1.10), exercise-based CR may result in a large reduction in cardiovascular mortality (RR 0.58, 95% CI 0.43 to 0.78; 8 trials) and MI (RR 0.67, 95% CI 0.50 to 0.90; 10 trials). Evidence is uncertain for CABG (RR 0.66, 95% CI 0.34 to 1.27; 4 trials), and PCI (RR 0.76, 95% CI 0.48 to 1.20; 3 trials). Meta-regression showed benefits in outcomes were independent of CHD case mix, type of CR, exercise dose, follow-up length, publication year, CR setting, study location, sample size or risk of bias. There was evidence that exercise-based CR may slightly increase HRQoL across several subscales (SF-36 mental component, physical functioning, physical performance, general health, vitality, social functioning and mental health scores) up to 12 months' follow-up; however, these may not be clinically important differences. The eight trial-based economic evaluation studies showed exercise-based CR to be a potentially cost-effective use of resources in terms of gain in quality-adjusted life years (QALYs).

AUTHORS' CONCLUSIONS

This updated Cochrane Review supports the conclusions of the previous version, that exercise-based CR provides important benefits to people with CHD, including reduced risk of MI, a likely small reduction in all-cause mortality, and a large reduction in all-cause hospitalisation, along with associated healthcare costs, and improved HRQoL up to 12 months' follow-up. Over longer-term follow-up, benefits may include reductions in cardiovascular mortality and MI. In the last decade, trials were more likely to include females, and be undertaken in LMICs, increasing the generalisability of findings. Well-designed, adequately-reported RCTs of CR in people with CHD more representative of usual clinical practice are still needed. Trials should explicitly report clinical outcomes, including mortality and hospital admissions, and include validated HRQoL outcome measures, especially over longer-term follow-up, and assess costs and cost-effectiveness.

Stent edge vascular response and in-stent geometry after aerobic exercise

The purpose of the present study was to investigate the edge vascular response in patients treated with second-generation drug-eluting stents (DES) after 3 months of aerobic exercise intervention. Thirty-two patients with significant coronary artery disease underwent percutaneous coronary intervention with DES implantation prior to randomization to aerobic interval training (AIT, 14 patients) versus moderate continuous training (MCT, 18 patients). Plaque changes were assessed using grayscale and radiofrequency intravascular ultrasound at baseline and follow-up. The main endpoints were changes in plaque burden and necrotic core content in the 5-mm proximal and distal stent edges. Plaque burden in the distal stent edges decreased significantly in both groups (AIT: − 3.3%; MCT: − 0.4%, p = 0.01 for both), and more in the AIT group (p = 0.048). Necrotic core content decreased significantly in the distal stent edges in both groups (− 2.1 mm³ in AIT, − 0.3 mm³ in MCT, p = 0.01 for both), and more in the AIT group (p = 0.03). There were no significant changes in proximal stent edges or in in-stent geometry at follow-up. In this small study of patients treated with DES implantation, 3 months of aerobic exercise training demonstrated decreased plaque burden and necrotic core content in the distal stent edges, with larger reductions in the AIT group.

Effects of rehabilitation exercise on coronary artery after percutaneous coronary intervention in patients with coronary heart disease: a systematic review and meta-analysis

Purpose: The purpose of this study is to evaluate the effects of rehabilitation exercise on coronary artery of the patients with coronary heart disease (CHD) after percutaneous coronary intervention (PCI).Methods: We searched Medline, EMBASE, Cochrane CENTRAL databases, ISI Web of Science databases, Chinese Biological Medicine Data Base, Chinese knowledge resources, and Wan Fang database. Two researchers independently screened the literature databases, and assessed methodological qualities using the Physiotherapy Evidence Database scale and extracted data.Results: The coronary restenosis rate in rehabilitation exercise group was 10.8% (23/212), and that in the control group was 21% (48/229). Patients with rehabilitation exercise showed a significant reduction in restenosis rate, compared to the control group ((pooled OR: 0.46, 95% CI: 0.26-0.82, p < 0.01); heterogeneity: Chi²=3.86, df =5 (p = 0.57); I²=0%). In addition, the late luminal loss per stent in the rehabilitation exercise group was significantly smaller than that in the control group ((pooled MD: -0.33, 95% CI: -0.52 to -0.13, p < 0.01); heterogeneity: Chi²=0.27, df =1 (p = 0.60); I²=0%).Conclusions: Appropriate rehabilitation exercise reduces the incidence of coronary restenosis after PCI in patients with CHD and contributes to a significant reduction in late luminal loss in the stented coronary segment.Implications for RehabilitationAppropriate rehabilitation exercise can reduce the incidence of coronary restenosis after percutaneous coronary intervention in patients with coronary heart disease.Appropriate rehabilitation exercise contributes to a reduction in late luminal loss in the stented coronary segment.

Exercise-based cardiac rehabilitation for coronary heart disease

BACKGROUND

Coronary heart disease (CHD) is the single most common cause of death globally. However, with falling CHD mortality rates, an increasing number of people live with CHD and may need support to manage their symptoms and prognosis. Exercise-based cardiac rehabilitation (CR) aims to improve the health and outcomes of people with CHD. This is an update of a Cochrane systematic review previously published in 2011.

OBJECTIVES

To assess the effectiveness and cost-effectiveness of exercise-based CR (exercise training alone or in combination with psychosocial or educational interventions) compared with usual care on mortality, morbidity and HRQL in patients with CHD.To explore the potential study level predictors of the effectiveness of exercise-based CR in patients with CHD.

SEARCH METHODS

We updated searches from the previous Cochrane review, by searching Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 6, 2014) from December 2009 to July 2014. We also searched MEDLINE (Ovid), EMBASE (Ovid), CINAHL (EBSCO) and Science Citation Index Expanded (December 2009 to July 2014).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of exercise-based interventions with at least six months' follow-up, compared with a no exercise control. The study population comprised men and women of all ages who have had a myocardial infarction (MI), coronary artery bypass graft (CABG) or percutaneous coronary intervention (PCI), or who have angina pectoris, or coronary artery disease. We included RCTs that reported at least one of the following outcomes: mortality, MI, revascularisations, hospitalisations, health-related quality of life (HRQL), or costs.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened all identified references for inclusion based on the above inclusion and exclusion criteria. One author extracted data from the included trials and assessed their risk of bias; a second review author checked data. We stratified meta-analysis by the duration of follow up of trials, i.e. short-term: 6 to 12 months, medium-term: 13 to 36 months, and long-term: > 3 years.

MAIN RESULTS

This review included 63 trials which randomised 14,486 people with CHD. This latest update identified 16 new trials (3872 participants). The population included predominantly post-MI and post-revascularisation patients and the mean age of patients within the trials ranged from 47.5 to 71.0 years. Women accounted for fewer than 15% of the patients recruited. Overall trial reporting was poor, although there was evidence of an improvement in quality of reporting in more recent trials.As we found no significant difference in the impact of exercise-based CR on clinical outcomes across follow-up, we focused on reporting findings pooled across all trials at their longest follow-up (median 12 months). Exercise-based CR reduced cardiovascular mortality compared with no exercise control (27 trials; risk ratio (RR) 0.74, 95% CI 0.64 to 0.86). There was no reduction in total mortality with CR (47 trials, RR 0.96, 95% CI 0.88 to 1.04). The overall risk of hospital admissions was reduced with CR (15 trials; RR 0.82, 95% CI 0.70 to 0.96) but there was no significant impact on the risk of MI (36 trials; RR 0.90, 95% CI 0.79 to 1.04), CABG (29 trials; RR 0.96, 95% CI 0.80 to 1.16) or PCI (18 trials; RR 0.85, 95% CI 0.70 to 1.04).There was little evidence of statistical heterogeneity across trials for all event outcomes, and there was evidence of small study bias for MI and hospitalisation, but no other outcome. Predictors of clinical outcomes were examined across the longest follow-up of studies using univariate meta-regression. Results show that benefits in outcomes were independent of participants' CHD case mix (proportion of patients with MI), type of CR (exercise only vs comprehensive rehabilitation) dose of exercise, length of follow-up, trial publication date, setting (centre vs home-based), study location (continent), sample size or risk of bias.Given the heterogeneity in outcome measures and reporting methods, meta-analysis was not undertaken for HRQL. In five out of 20 trials reporting HRQL using validated measures, there was evidence of significant improvement in most or all of the sub-scales with exercise-based CR compared to control at follow-up. Four trial-based economic evaluation studies indicated exercise-based CR to be a potentially cost-effective use of resources in terms of gain in quality-adjusted life years.The quality of the evidence for outcomes reported in the review was rated using the GRADE method. The quality of the evidence varied widely by outcome and ranged from low to moderate.

AUTHORS' CONCLUSIONS

This updated Cochrane review supports the conclusions of the previous version of this review that, compared with no exercise control, exercise-based CR reduces the risk of cardiovascular mortality but not total mortality. We saw a significant reduction in the risk of hospitalisation with CR but not in the risk of MI or revascularisation. We identified further evidence supporting improved HRQL with exercise-based CR. More recent trials were more likely to be well reported and include older and female patients. However, the population studied in this review still consists predominantly of lower risk individuals following MI or revascularisation. Further well conducted RCTs are needed to assess the impact of exercise-based CR in higher risk CHD groups and also those presenting with stable angina. These trials should include validated HRQL outcome measures, explicitly report clinical event outcomes including mortality and hospital admissions, and assess costs and cost-effectiveness.

Impact of exercise-based cardiac rehabilitation on de novo coronary lesion in patients with drug eluting stent

Objective

To compare the rate of progression of de novo lesion between the cardiac rehabilitation (CR) and control groups.

Methods

This is a retrospective observational study. Patients who received drug-eluting stent (DES) due to acute coronary syndrome were included as subjects. The CR group received eight weeks of early CR program, and sustained a self-exercise program in the homes. The control group was instructed to exercise independently. Nine months after the first insertion of DES, we implemented follow-up coronary angiography, and compared the rate of progression of de novo lesion by quantitative angiographic measurement between the two groups.

Results

A total of 81 patients were recruited as subjects to CR group (n=32) or control group (n=49). At nine months, late luminal loss was 0.04±0.23 mm in the CR group and 0.00±0.31 mm in the control group (p=0.54, observed power=0.10). Late loss was -0.90%±9.53% in the CR group and 0.80%±11.15% in the control group (p=0.58, observed power=0.05). No target lesion revascularization procedures were needed in the CR group, while two in the control group (p=0.25). In the CR group, mean VO_2max was significantly improved from 24.36±5.00 to 27.68±5.24 mL/kg/min (p<0.001).

Conclusion

We could not observe a statistically significant difference in the progression rate of de novo lesion between the CR and control groups. Thus the current amount of nine months exercise-based CR program does not seem to have a distinct impact on the retardation of de novo coronary lesion in patients who received percutaneous coronary intervention with DES.