Cardiac Rehabilitation and Exercise Prescription in Symptomatic Patients with Non-Obstructive Coronary Artery Disease-a Systematic Review

Novel diagnostic approaches and management of coronary microvascular dysfunction

The mechanism underlying ischaemic heart disease (IHD) has been primarily attributed to obstructive coronary artery disease (CAD). However, non-obstructive coronary arteries are identified in >50% of patients undergoing elective coronary angiography, recently leading to growing interest in the investigation and management of angina/ischaemia with non-obstructive coronary arteries (ANOCA/INOCA). INOCA is an umbrella term encompassing a multiple spectrum of possible pathogenetic entities, including coronary vasomotor disorders which consist of two major endotypes: coronary microvascular dysfunction (CMD) and vasospastic angina. Both conditions can coexist and be associated with concomitant obstructive CAD. Particularly, CMD refers to myocardial ischaemia due to reduced vasodilatory capacity of coronary microcirculation secondary to structural remodelling or impaired resting microvascular tone (functional) or a combination of both. CMD is not a benign condition and is more prevalent in women presenting with chronic coronary syndrome compared to men. In this setting, an impaired coronary flow reserve has been associated with increased risk of major adverse cardiovascular events. ANOCA/INOCA patients also experience impaired quality of life and associated increased healthcare costs. Therefore, research in this scenario has led to better definition, classification, and prognostic stratification based on the underlying pathophysiological mechanisms. The development and validation of non-invasive imaging modalities, invasive coronary vasomotor function testing and angiography-derived indices provide a comprehensive characterisation of CMD. The present narrative review aims to summarise current data relating to the diagnostic approach to CMD and provides details on the sequence that therapeutic management should follow.

Coronary artery disease management in older adults: revascularization and exercise training

The mean age of patients with coronary artery disease (CAD) is steadily increasing. In older patients, there is a tendency to underutilize invasive approach, coronary revascularization, up-to-date pharmacological therapies, and secondary prevention strategies, including cardiac rehabilitation. Older adults with CAD commonly exhibit atypical symptoms, multi-vessel disease involvement, complex coronary anatomy, and a higher presence of risk factors and comorbidities. Although both invasive procedures and medical treatments are characterized by a higher risk of complications, avoidance may result in a suboptimal outcome. Often, overlooked factors, such as coronary microvascular disease, malnutrition, and poor physical performance, play a key role in determining prognosis, yet they are not routinely assessed or addressed in older patients. Historically, clinicians have relied on sub-analyses or observational findings to make clinical decisions, as older adults were frequently excluded or under-represented in clinical studies. Recently, dedicated evidence through randomized clinical trials has become available for older CAD patients. Nevertheless, the management of older CAD patients still raises several important questions. This review aims to comprehensively summarize and critically evaluate this emerging evidence, focusing on invasive management and coronary revascularization. Furthermore, it seeks to contextualize these interventions within the framework of improved risk stratification tools for older CAD patients, through user-friendly scales along with emphasizing the importance of promoting physical activity and exercise training to enhance the outcomes of invasive and medical treatments. This comprehensive approach may represent the key to improving prognosis in the complex and growing patient population of older CAD patients.

Canadian Cardiovascular Society/Canadian Women's Heart Health Alliance Clinical Practice Update on Myocardial Infarction With No Obstructive Coronary Artery Disease (MINOCA)

Myocardial infarction with no obstructive coronary artery disease (MINOCA) represents 6%-15% of all acute coronary syndromes, and women are disproportionately represented. MINOCA is an encompassing preliminary diagnosis, and emerging evidence supports a more expansive comprehensive diagnostic and therapeutic clinical approach. The current clinical practice update summarizes the latest evidence regarding the epidemiology, clinical presentation, and diagnostic evaluation of MINOCA. A cascaded approach to diagnostic workup is outlined for clinicians, for noninvasive and invasive diagnostic pathways, depending on clinical setting and local availability of diagnostic modalities. Evidence concerning the nonpharmacological and pharmacological treatment of MINOCA are presented and summarized according to underlying cause of MINOCA, with practical tips on the basis of expert opinion, outlining a real-life, evidence-based, comprehensive approach to management of this challenging condition.

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.

Targeted Therapies for Microvascular Disease

Coronary microvascular dysfunction (CMD) is a common cause of ischemia but no obstructive coronary artery disease that results in an inability of the coronary microvasculature to meet myocardial oxygen demand. CMD is challenging to diagnose and manage due to a lack of mechanistic research and targeted therapy. Recent evidence suggests we can improved patient outcomes by stratifying antianginal therapies according to the diagnosis revealed by invasive assessment of the coronary microcirculation. This review article appraises the evidence for management of CMD, which includes treatment of cardiovascular risk, antianginal therapy and therapy for atherosclerosis.

Targeted Therapies for Microvascular Disease

Coronary microvascular dysfunction (CMD) is a common cause of ischemia but no obstructive coronary artery disease that results in an inability of the coronary microvasculature to meet myocardial oxygen demand. CMD is challenging to diagnose and manage due to a lack of mechanistic research and targeted therapy. Recent evidence suggests we can improved patient outcomes by stratifying antianginal therapies according to the diagnosis revealed by invasive assessment of the coronary microcirculation. This review article appraises the evidence for management of CMD, which includes treatment of cardiovascular risk, antianginal therapy and therapy for atherosclerosis.

Coronary vascular dysfunction is associated with increased risk of death in patients with peripheral artery disease

BACKGROUND

Peripheral artery disease (PAD) and coronary vascular dysfunction are common in patients with cardiometabolic disease. Neither the prevalence of coronary vascular dysfunction among patients with PAD nor the prognostic impact with these two conditions present together has been well studied.

METHODS

Consecutive patients who underwent PET MPI were analyzed for presence of coronary vascular dysfunction [myocardial blood flow reserve (MBFR) < 2]. Cox regression was used to examine the association of reduced MBFR with mortality in patients with PAD, as well as the association of comorbid MBFR < 2 and PAD with all-cause death.

RESULTS

Among 13,940 patients, 1936 (14%) had PAD, 7782 (56%) had MBFR < 2 and 1346 (10%) had both PAD and MBFR < 2. Reduced MBFR was very common (69.5%) and was associated with increased risk of all-cause death (HR 1.69, 95%CI 1.32, 2.16, p < 0.01) in patients with PAD. Patients with both PAD and MBFR < 2, and those with either PAD or reduced MBFR had increased risk of death compared to those with neither condition: PAD + MBFR < 2 [(HR 95%CI), 2.30; 1.97-2.68], PAD + MBFR ≥ 2 (1.37; (1.08-1.72), PAD - MBFR < 2 (1.98; 1.75-2.25), p < 0.001 for all).

CONCLUSION

Coronary vascular dysfunction was common in patients with PAD and was associated with increased risk of death.

Long-term effects of e-Health secondary prevention on cardiovascular health: a systematic review and meta-analysis

AIMS

Despite the well-documented short-to-medium-term effectiveness of e-Health (electronic health) secondary prevention interventions on patients with cardiovascular disease (CVD), there is limited empirical evidence regarding long-term effectiveness. This review aims to evaluate the long-term effects of e-Health secondary prevention interventions on the health outcomes of patients with CVD.

METHODS AND RESULTS

This systematic review and meta-analysis followed Cochrane Handbook for Systematic Reviews of Interventions. EMBASE, Medline, Web of Science, and Scopus were searched from 1990 to May 2022. Randomized controlled trials investigating the effects of e-Health secondary prevention on health outcomes of CVD patients that collected endpoint data at ≥ 12 months were included. RevMan 5.3 was used for risk of bias assessment and meta-analysis. Ten trials with 1559 participants were included. Data pooling suggested that e-Health programmes have significantly reduced LDL cholesterol [n = 6; SMD = -0.26, 95% confidence interval (CI): (-0.38, -0.14), I2 = 17%, P < 0.001]; systolic blood pressure [n = 5; SMD = -0.46, 95% CI: (-0.84, -0.08), I2 = 90%, P = 0.02]; and re-hospitalization, reoccurrence, and mortality [risk ratio = 0.36, 95% CI: (0.17, 0.77), I2 = 0%, P = 0.009]. Effects on behavioural modification, physiological outcomes of body weight and blood glucose, and quality of life were inconclusive.

CONCLUSION

e-Health secondary prevention is effective in improving long-term management of risk factors and reducing the reoccurrence of cardiac events in patients with CVD. Results are inconclusive for behaviour modification and quality of life. Exploring, implementing, and strengthening strategies in e-Health secondary prevention programmes that focus on maintaining behaviour changes and enhancing psychosocial elements should be undertaken.

REGISTRATION

PROSPERO CRD42022300551.

Aerobic high-intensity interval exercise training in patients with angina and no obstructive coronary artery disease: feasibility and physiological effects

Aims

Patients with chest pain and normal coronary angiogram [angina with normal coronary arteries (ANOCA)] constitute a therapeutic problem with considerable functional limitation and reduced quality of life. The aims of the current pilot study were to (i) explore if a structured aerobic high-intensity interval training (HIT) program for 12 weeks was feasible in patients with ANOCA, and (ii) to assess mechanisms related to symptoms in this population.

Methods and results

Sixteen patients with ANOCA underwent a 3-month aerobic HIT program with one-to-one monitored exercise sessions on treadmill in a 4 min × 4 manner, three times a week. Four patients served as controls. Coronary flow velocity reserve (CFVR) transthoracic Doppler, flow-mediated vasodilation (FMD) and VO_2max was measured at baseline and after 12 weeks. The average attendance to training sessions was 82.3% ± 10.1 (56-94). CFVR in the training group increased from 2.50 ± 0.48 to 3.04 ± 0.71 (P < 0.001) whereas FMD increased from 4.19 ± 2.42% to 8.28 ± 2.85% (P < 0.001). Improvement in CFVR correlated with the relative improvement in FMD (R = 0.45, P = 0.047). This was associated with an increase in VO_2max from 28.75 ± 6.51 mL/kg/min to 31.93 ± 6.46 mL/kg/min (P < 0.001).

Conclusion

A 3-month program of monitored HIT was feasible, with high adherence resulting in improved functional capacity in patients with ANOCA. CFVR improved and this improvement was associated with improved FMD.

ClinicalTrialsgov Identifier

NCT02905630.

Targeted Therapies for Microvascular Disease

Coronary microvascular dysfunction (CMD) is a common cause of ischemia but no obstructive coronary artery disease that results in an inability of the coronary microvasculature to meet myocardial oxygen demand. CMD is challenging to diagnose and manage due to a lack of mechanistic research and targeted therapy. Recent evidence suggests we can improved patient outcomes by stratifying antianginal therapies according to the diagnosis revealed by invasive assessment of the coronary microcirculation. This review article appraises the evidence for management of CMD, which includes treatment of cardiovascular risk, antianginal therapy and therapy for atherosclerosis.

Phenotype-based management of coronary microvascular dysfunction

40-70% of patients undergoing invasive coronary angiography with signs and symptoms of ischemia are found to have no obstructive coronary artery disease (INOCA). When this heterogeneous group undergo coronary function testing, approximately two-thirds have demonstrable coronary microvascular dysfunction (CMD), which is independently associated with adverse prognosis. There are four distinct phenotypes, or subgroups, each with unique pathophysiological mechanisms and responses to therapies. The clinical phenotypes are microvascular angina, vasospastic angina, mixed (microvascular and vasospastic), and non-cardiac symptoms (reclassification as non-INOCA). The Coronary Vasomotor Disorders International Study Group (COVADIS) have proposed standardized criteria for diagnosis. There is growing awareness of these conditions among clinicians and within guidelines. Testing for CMD can be done using invasive or non-invasive modalities. The CorMicA study advocates the concept of 'functional angiography' to guide stratified medical therapy. Therapies broadly fall into two categories: those that modulate cardiovascular risk and those to alleviate angina. Management should be tailored to the individual, with periodic reassessment for efficacy. Phenotype-based management is a worthy endeavor for both patients and clinicians, aligning with the concept of 'precision medicine' to improve prognosis, symptom burden, and quality of life. Here, we present a contemporary approach to the phenotype-based management of patients with INOCA.

Contemporary and future invasive coronary vasomotor function testing and treatment in patients with ischaemia with no obstructive coronary arteries

In the current review, we emphasize the importance of diagnostics and therapy in patients with ischaemia with no obstructive coronary arteries (INOCA). The importance of the diagnostic coronary function test (CFT) procedure is described, including future components including angiography-derived physiology and invasive continuous thermodilution. Furthermore, the main components of treatment are discussed. Future directions include the national registration ensuring a high quality of INOCA care, besides a potential source to improve our understanding of pathophysiology in the various phenotypes of coronary vascular dysfunction, the diagnostic CFT procedure, and treatment.

Management of ischaemia with non-obstructive coronary arteries (INOCA)

Up to half of patients undergoing elective coronary angiography for the investigation of chest pain do not present with evidence of obstructive coronary artery disease. These patients are often discharged with a diagnosis of non-cardiac chest pain, yet many could have an ischaemic basis for their symptoms. This type of ischaemic chest pain in the absence of obstructive coronary artery disease is referred to as INOCA (ischaemia with non-obstructive coronary arteries). This comprehensive review of INOCA management looks at why these patients require treatment, who requires treatment based on diagnostic evaluation, what clinical treatment targets should be considered, how to treat patients using a personalised medicine approach, when to initiate treatment, and where future research is progressing.

Outpatient Management of Patients With Angina With No Obstructive Coronary Arteries: How to Come to a Proper Diagnosis and Therapy

Two-thirds of women and one-third of men who undergo a clinically indicated coronary angiography for stable angina, have no obstructive coronary artery disease (CAD). Coronary vascular dysfunction is a highly prevalent underlying cause of angina in these so called “Angina with No Obstructive Coronary Arteries (ANOCA)” patients, foremost in middle aged women. Coronary vascular dysfunction encompasses various endotypes, namely epicardial and microvascular coronary spasms, impaired vasodilatation, and increased microvascular resistance. ANOCA patients, especially those with underlying coronary vascular dysfunction, have an adverse cardiovascular prognosis, poor physical functioning, and a reduced quality of life. Since standard ischemia detection tests and coronary angiograms are not designed to diagnose coronary vascular dysfunction, this ischemic heart disease is often overlooked and hence undertreated. But adequate diagnosis is vital, so that treatment can be started to reduce symptoms, reduce healthcare costs and improve quality of life and cardiovascular prognosis. The purpose of this review is to give a contemporary overview of ANOCA with focus on coronary vascular dysfunction. We will provide a possible work-up of patients suspected of coronary vascular dysfunction in the outpatient clinical setting, based on the latest scientific insights and international consensus documents. We will discuss the value of ischemia detection testing, and non-invasive and invasive methods to diagnose coronary vascular dysfunction. Furthermore, we will go into pharmacological and non-pharmacological therapeutic options including anti-anginal regimens and lifestyle interventions.

ANMCO POSITION PAPER: Prognostic and therapeutic relevance of non-obstructive coronary atherosclerosis

Atherosclerosis often affects the coronary arterial tree. Frequently the disease does not translate in significant narrowing of the vessels, thus determining only a non-obstructive disease. This condition that is described as non-obstructive coronary artery disease (NobsCAD) should be distinguished from the absence of disease (i.e. smooth coronary arteries) as it carries a specific prognostic value. The detection and reporting of NobsCAD should prompt preventive measures that can be individualized upon the degree of the underlying burden of disease. The accompanying clinical condition, the other cardiovascular risk factors present, and the description of the severity and extent of NobsCAD should provide the framework for an individualized treatment that should also consider the best available scientific evidence and guidelines. The description of NobsCAD represents important information to be collected whenever a coronary angiogram (both invasive and non-invasive) is performed. Treating the patient according to the presence and extent of NobsCAD offers prognostic benefits well beyond those offered by considering only the traditional cardiovascular risk factors. In order to reach this goal, NobsCAD should not be confused with the absence of coronary atherosclerosis or even ignored when detected as if it was a trivial information to provide.

Novel advances in cardiac rehabilitation : Position paper from the Working Group on Preventive Cardiology and Cardiac Rehabilitation of the Netherlands Society of Cardiology

Cardiac rehabilitation (CR) has evolved as an important part of the treatment of patients with cardiovascular disease. However, to date, its full potential is fairly underutilised. This review discusses new developments in CR aimed at improving participation rates and long-term effectiveness in the general cardiac population. It consecutively highlights new or challenging target groups, new delivery modes and new care pathways for CR programmes. These new or challenging target groups include patients with atrial fibrillation, obesity and cardiovascular disease, chronic coronary syndromes, (advanced) chronic heart failure with or without intracardiac devices, women and frail elderly patients. Also, the current evidence regarding cardiac telerehabilitation and loyalty programmes is discussed as new delivery modes for CR. Finally, this paper discusses novel care pathways with the integration of CR in residual risk management and transmural care pathways. These new developments can help to make optimal use of the benefits of CR. Therefore we should seize the opportunities to reshape current CR programmes, broaden their applicability and incorporate them into or combine them with other cardiovascular care programmes/pathways.

Sex differences in non-obstructive coronary artery disease

Ischaemic heart disease is a leading cause of morbidity and mortality in both women and men. Compared with men, symptomatic women who are suspected of having myocardial ischaemia are more likely to have no obstructive coronary artery disease (CAD) on coronary angiography. Coronary vasomotor disorders and coronary microvascular dysfunction (CMD) have been increasingly recognized as important contributors to angina and adverse outcomes in patients with no obstructive CAD. CMD from functional and structural abnormalities in the microvasculature is associated with adverse cardiac events and mortality in both sexes. Women may be particularly susceptible to vasomotor disorders and CMD due to unique factors such as inflammation, mental stress, autonomic, and neuroendocrine dysfunction, which predispose to endothelial dysfunction and CMD. CMD can be detected with coronary reactivity testing and non-invasive imaging modalities; however, it remains underdiagnosed. This review focuses on sex differences in presentation, pathophysiologic risk factors, diagnostic testing, and prognosis of CMD.

The effect of nicorandil in patients with cardiac syndrome X: A meta-analysis of randomized controlled trials

BACKGROUND

The prevalence of cardiac syndrome X (CSX) is considerable. Some patients show recurrent angina attacks and have a poor prognosis. However, the knowledge of CSX pathophysiological mechanism is still limited, and the treatment fails to achieve a satisfactory suppression of symptoms. Nicorandil has a beneficial effect on improving coronary microvascular dysfunction (CMD). This study aims to evaluate the clinical effects and safety of nicorandil on CSX patients.

METHODS

The Cochrane Library, Pubmed, EMBASE, ClinicalTrials.gov and 4 Chinese databases were searched to identify relevant studies. The Cochrane "Risk of bias" tool was used to assess the methodological quality of eligible studies. Meta-analysis was performed by RevMan 5.3 software. The Eggers test and meta-regression were performed by software Stata 14.0. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

RESULTS

Twenty four randomized controlled trials (RCTs) involving 2323 patients were included. Most of the included studies were classified as having an unclear risk of bias because of poor reported methodology. The main outcomes are angina symptoms improvement, resting electrocardiogram (ECG) improvement, treadmill test result, and endothelial function. Meta-analysis showed that nicorandil had some benefit on improving angina symptoms (RR 1.24, 95% CI 1.19 to 1.29, I = 20%, P < .00001), resting ECG (RR = 1.24, 95% IC: 1.15 to 1.33, I = 0%, P < .00001), and prolonged the time to 1 mm ST-segment depression in treadmill test result (WMD = 38.41, 95% IC: 18.46 to 58.36, I = 0%, P = .0002). Besides nicorandil could reduce the level of endothelin-1 (ET-1) (SMD = -2.22, 95% IC: -2.61 to -1.83, I = 77%, P < .00001) and increase the level of nitric oxide (NO) (WMD = 27.45, 95% IC: 125.65 to 29.24, I = 81%, P < .00001). No serious adverse drug event was reported. The Eggers test showed that significant statistical publication bias was detected (Eggers test P = .000). The quality of evidence ranged from very low to low.

CONCLUSIONS

Nicorandil shows the potential of improving angina symptoms, ECG, and endothelial dysfunction in patients with CSX. However, there is insufficient evidence for the clinical benefits of nicorandil due to the very low-quality evidence.

Effects of a Cardiac Rehabilitation Program Versus Usual Care on Cardiopulmonary Function in Patients With Cardiac Syndrome X

PURPOSE

Because of uncertainty in the pathophysiological process, the treatment of cardiac syndrome X (CSX) is still under study. Addressing the effects of cardiac rehabilitation (CR) can help promote the prescription of this modality as an adjuvant therapy for these patients.

METHODS

This study was performed on 30 patients with effort-induced angina pectoris using a positive exercise test and/or myocardial perfusion scan in the absence of obvious stenosis or a stenosis of <50% on coronary angiography. The patients were divided into the CR and usual care (UC) groups and underwent cardiopulmonary exercise testing with gas exchange analysis before and after the study. The Duke Treadmill Score was used to compare prognosis and survival estimates of patients.

RESULTS

An increase in peak oxygen uptake ((Equation is included in full-text article.)O2) was significantly higher in the CR group than in the control group (P = .017). Resting (Equation is included in full-text article.)O2 was also increased in the CR group, but its difference with the UC group was not statistically significant. Resting O2 pulse was increased in the CR group, which significantly differed between groups (P = .041). Exercise test duration and the Duke Treadmill Score significantly increased in the CR group as compared with the UC group (P = .003 and P = .002, respectively). Also, recovery heart rate in the first minute was significantly improved in CR group.

CONCLUSION

Adding a 4-wk course of CR to UC for patients with CSX not only increased the Duke Treadmill Score and exercise test duration but also improved the resting O2 pulse, peak (Equation is included in full-text article.)O2, and first-minute recovery heart rate.