Exercise training and cardiac autonomic function following coronary artery bypass grafting: a systematic review and meta-analysis

Cardiac Rehabilitation in Saudi Arabia: Current Status and Future Directions

PURPOSE OF REVIEW

Cardiovascular diseases (CVDs) are the leading cause of mortality in Saudi Arabia. Cardiac rehabilitation (CR) is one of the well-known interventions to control and minimize the burden of CVDs. Despite recommendations, CR utilization remains suboptimal in Saudi Arabia due to many reasons, including limited awareness, logistical barriers, shortage of specialized facilities and trained professionals, and perceptions about CVDs illness. This review is to evaluate the current status, effectiveness, accessibility, and challenges of CR utilization in Saudi Arabia, and to explore potential future directions for improving these services. The review addresses key questions regarding the incidence of CVDs, the characteristics of existing CR programs, barriers to CR access, and stakeholder perspectives.

RECENT FINDINGS

Recent studies demonstrate that the effectiveness of CR, particularly exercise training, in improving outcomes for post-coronary artery bypass grafting (CABG) patients is well-documented, though data on its impact on other cardiac conditions is limited. There are significant barriers to CR utilization in Saudi Arabia, including limited awareness, logistical challenges, a shortage of specialized facilities and trained professionals, and cultural perceptions about CVD. Stakeholder perspectives highlight the necessity for culturally sensitive and inclusive approaches, particularly in addressing gender-specific needs and enhancing patient-provider communication. The Saudi Vision 2030 presents opportunities to expand and enhance CR services in alignment with international standards. This review found that while CR is a crucial intervention for managing CVDs, its utilization in Saudi Arabia is suboptimal due to various barriers. To improve CR access and effectiveness, future strategies should focus on increasing public and professional awareness, developing infrastructure, training healthcare professionals, and fostering public-private partnerships. These measures are essential to making CR more accessible and tailored to the diverse needs of the Saudi population, ultimately enhancing the quality of cardiovascular care and patient outcomes in the region.

Exercise-based cardiac rehabilitation for patients with coronary heart disease: a systematic review and evidence mapping study

INTRODUCTION

Exercise-based cardiac rehabilitation (CR) plays a critical role in coronary heart disease (CHD) management. There is a heritage in the effect of exercise-based CR with different exercise programs or intervention settings. This study developed an evidence matrix that systematically assesses, organizes, and presents the available evidence regarding exercise-based CR in CHD management.

EVIDENCE ACQUISITION

A comprehensive literature search was conducted across six databases. Two reviewers screened the identified literature, extracted relevant data, and assessed the quality of the studies. An evidence-mapping framework was established to present the findings in a structured manner. Bubble charts were used to represent the included systematic reviews (SRs). The charts incorporated information, exercise prescriptions, outcome indicators, associated P values, research quality, and the number of original studies. A descriptive analysis summarized the types of CR, intervention settings, influential factors, and adverse events.

EVIDENCE SYNTHESIS

Sixty-two SRs were included in this analysis, focusing on six exercise types in addition to assessing major adverse cardiovascular events (MACE), cost and rehabilitation outcomes. The most commonly studied exercise types were unspecified (28 studies, 45.2%) and aerobic (11 studies, 17.7%) exercises. All-cause mortality was the most frequently reported MACE outcome (22 studies). Rehabilitation outcomes primarily centered around changes in cardiac function (135 outcomes from 39 SRs). Only 8 (12.9%) studies were rated as "high quality." No significant adverse events were observed in the intervention group. Despite some variations among the included studies, most SRs demonstrated the benefits of exercise in improving one or more MACE or rehabilitation outcomes among CHD patients.

CONCLUSIONS

The proportion of high-quality evidence remains relatively low. Limited evidence is available regarding the effectiveness of specific exercise types and specific populations, necessitating further evaluation.

Heart Rate Variability and Coronary Artery Bypass Grafting: A Systematic Review

Background

Coronary artery bypass grafting (CABG) is a well-established surgical procedure used to treat significant coronary artery disease. Nevertheless, unfavorable cardiovascular events and complications, including cardiac arrhythmias may be observed in patients after CABG. Previous studies have revealed a relationship between risk of cardiac arrhythmias and abnormal heart rate variability (HRV), which reflects adverse alterations in cardiac autonomic functioning, that may occur in patients after a CABG procedure. The aim of this article was to provide a systematic review of the major research findings in this area.

Methods

A literature search was carried out using PubMed, Cochrane, and Embase databases and relevant articles, published in English, were analyzed in detail.

Results

Studies performed so far have shown time depending changes in HRV after CABG. Time and frequency domain HRV decrease acutely after CABG but recover almost completely to pre-operative values by 6 months after surgery. Some preoperative clinical states such as: heart failure, type 2 diabetes mellitus and depression adversely affect post-CABG HRV. Finally, post-CABG cardiac rehabilitation appears to improve exercise capacity and speed up recovery of HRV.

Conclusions

Generally, traditional time and frequency domain HRV parameters fail to predict complications post-CABG. Altered non-linear measures of HRV may identify subgroups of subjects at increased risk of potential complications, including atrial fibrillation post-CABG. However, data available currently does not appear to unequivocally support the hypothesis that early HRV assessment in post-CABG patients predicts long-term mortality.

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.

Comment on: "exercise training and cardiac autonomic function following coronary artery bypass grafting: a systematic review and meta-analysis"

BACKGROUND

Low cardiorespiratory fitness is associated with poor prognosis in individuals with coronary artery disease and after coronary artery bypass grafting surgery. Thus, we comment about a meta-analysis that adds important information about the effect of exercise training on cardiac autonomic function in individuals following coronary artery bypass grafting surgery.

MAIN BODY

The study by Kushwaha et al. showed positive effects for heart rate variability and heart rate recovery in subjects after coronary artery bypass grafting surgery in response to acute physical training. These data are relevant, since heart rate variability is an independent predictor of for all-cause and cardiovascular mortality for individuals with cardiovascular disorders. Additionally, attenuated heart rate recovery is associated with increased risk for the same outcomes. Moreover, we summarize the quantitative data from studies that compared the effect of physical training in comparison with control group in cardiorespiratory fitness in adults following coronary artery bypass grafting.

CONCLUSIONS

Our findings suggest that improvements in peak oxygen consumption result in an additional benefit in adults following coronary artery bypass grafting. Considered that, the increased cardiorespiratory fitness is an independent predictor of longer survival in coronary artery disease.