Impact of Physical Activity on Coronary Plaque Volume and Components in Acute Coronary Syndrome Patients After Early Phase II Cardiac Rehabilitation

Defining "Vulnerable" in coronary artery disease: predisposing factors and preventive measures

The likelihood of a plaque to cause an acute coronary syndrome (ACS) depends on several factors, both lesion- and patient-related. One of the most investigated and established contributing factors is the presence of high-risk or "vulnerable plaque" characteristics, which have been correlated with increased incidence of major adverse cardiovascular events (MACE). The recognition, however, that a significant percentage of vulnerable plaques do not result in causing clinical events has led the scientific community towards the more multifaceted concept of "vulnerable patients". Incorporating the morphological features of an atherosclerotic plaque into its hemodynamic surroundings can better predict the chance of its disruption, as altered fluid dynamics play a significant role in plaque destabilization. The advances in coronary imaging and the field of computational fluid dynamics (CFD) can contribute to develop more accurate lesion- and patient-related ACS prediction models that take into account both the morphology of a plaque and the forces applied upon it. The aim of this review is to provide the latest data regarding the aforementioned predictive factors as well as relevant preventive measures.

Atherosclerotic plaque stabilization and regression

Atherosclerotic plaques represent a typical deterioration of arterial wall in atherosclerotic process and are the source of cardiovascular events. Plaque progression and composition represent a major risk for cardiovascular events. Therefore, recently many studies have assessed changes in plaque characteristics and their response to various treatment modalities. In the last two decades, improvement in plaque imaging modalities that can assess plaque volumes and composition enable to follow plaque characteristics in a non-invasive way. Clinical trials utilizing arterial imaging modalities have shown that reducing LDL cholesterol to low levels can reduce atherosclerotic plaque burden and favourably modify plaque composition. These outcomes have been achieved with statin therapy and newer lipid-lowering strategies such as protein convertase subtilisin/kexin type 9 inhibitors. Also, some anti-inflammatory drugs and other anti-atherosclerotic medications can lead to significant reduction in plaque burden. However, the data assessing association of plaque regression to reduction of cardiovascular events are limited. Therefore, the aim of this narrative review is to elucidate the possibilities and the role of plaque assessment and if it might offer the potential to guide personalized management of patients at risk for cardiovascular events in the future.

Relationship Between Advanced Glycation End Products Tissue Accumulation and Frailty in Patients Undergoing Cardiac Rehabilitation

Background

The advanced glycation end products (AGEs), which can be assessed through skin autofluorescence (SAF), have been linked to chronic kidney disease (CKD), diabetes mellitus (DM), and aging. However, it is unknown how frailty and SAF levels are associated with cardiovascular disease (CVD).

Methods

We enrolled 1,000 consecutive CVD patients who participated in phase II cardiac rehabilitation (CR) and underwent assessment of SAF between November 2015 and September 2017 at Juntendo University Hospital. Of these, 48 patients were excluded as duplicate cases, and a deficiency in SAF data led to the exclusion of an additional 146 patients. The final analysis included 806 patients.

Results

Seventy percent of patients were male, and the mean age was 67.0 ± 12.9 years. In this study, the patients were divided into two groups (high SAF group and low SAF group) based on the median SAF level (2.9 a.u.), which is known as a cutoff value to increase the risk of CVD in previous studies. Compared with the low SAF group (n = 368, 45.7%), the high SAF group (n = 438; 54.3%) was older, and the Kihon Checklist (KCL) total score and prevalence of DM and CKD were significantly higher (all, P < 0.05). Multivariate regression analyses demonstrated that age was the only independent associated factor (P < 0.05) in the low SAF group. Conversely, in the high SAF group, creatinine, hemoglobin A1c (HbA1c) and the sub-total KCL score (1 - 20) were independently associated with SAF levels (all, P < 0.05).

Conclusions

Frailty assessed by KCL is one of the factors significantly correlated with the accumulation of AGEs as well as creatinine, HbA1c and brain natriuretic peptide (BNP) levels in the high SAF group of patients with CVD undergoing phase II CR, who have the higher risk of the onset of CVD and all-cause mortality.

Plaque Stabilization and Regression, from Mechanisms to Surveillance and Clinical Strategies

With advances in therapies to reduce cardiovascular events and improvements in coronary imaging, an increasing number of clinical trials have demonstrated that treatments to reduce cardiovascular events in coronary artery disease are associated with favorable effects on atherosclerotic plaque size and characteristics. It has been observed that various drugs may induce plaque regression and enhance plaque stability after plaque formation. Numerous clinical trials have been conducted to verify the occurrence of plaque stabilization and regression and their beneficial effects on cardiovascular events. Using invasive imaging techniques such as intravascular ultrasound (IVUS) and optical coherence tomography (OCT), researchers have been able to gather evidence supporting the existence of coronary plaque stabilization and regression. In this review, we explore the possible mechanisms of plaque stabilization and regression, summarize the imaging features of plaque stabilization and regression, and assemble the evidence from clinical studies that have used different features as observational endpoints.

Mediterranean Diet Is a Predictor of Progression of Subclinical Atherosclerosis in a Mediterranean Population: The ILERVAS Prospective Cohort Study

Atherosclerotic cardiovascular disease remains a major health issue, often developing silently as subclinical atherosclerotic disease (SAD). The Mediterranean diet (MDiet) is known for its cardiovascular benefits, but the combined influence of both MDiet adherence and physical activity (PA) on SAD progression has not been previously documented. Objective: We aimed to investigate how adherence to a healthy lifestyle, defined as MDiet adherence and PA level, influences SAD progression in subjects from the ILERVAS cohort follow-up. Methods: A study on 3097 participants from the ILERVAS prospective cohort was conducted. MDiet adherence was assessed using the MEDAS score, and PA categories were established using the IPAQ, both categorized into low, moderate, and high levels. Two different lifestyle scores integrating the MDiet and PA categories were built. The presence of atherosclerotic plaques was assessed by carotid and femoral ultrasound examination. Demographic, clinical, and biochemical data were also obtained. Multivariable linear, logistic, and Poisson regression models adjusted for potential confounders were used to analyze the association between the lifestyle scores and SAD progression, as well as the MDiet and PA as separate variables and number of territories with plaque. Results: A healthier lifestyle score did not show an effect on SAD progression. However, a higher MEDAS score was associated with a 3% decrease in the number of territories with plaque (IRR 0.97, 95% CI 0.96-0.99, p < 0.001), suggesting a protective effect of the adherence to the MDiet. PA did not show a significant association (IRR 1.00, 95% CI 1.00-1.00, p = 0.269). Older age, hypertension, dyslipidemia, smoking, and lower eGFR were associated with SAD progression, while the female sex was protective (IRR 0.67, 95% CI 0.63-0.72, p < 0.001). Conclusions: The findings of this study show that higher adherence to the MDiet is associated with reduced incidence of SAD, indicating its potential role in cardiovascular prevention strategies. Although a higher lifestyle score or physical activity levels did not show any significant effect, promoting the MDiet, alongside managing traditional cardiovascular risk factors, could be an effective public health intervention to prevent atherosclerosis and reduce the burden of cardiovascular disease.

Effectiveness of Cardiac Rehabilitation in Enhancing Clinical Outcomes for Coronary Artery Disease: A Systematic Analysis

Cardiac rehabilitation (CR) is a structured intervention aimed at improving the clinical outcomes for patients with coronary artery disease (CAD). This systematic review assesses how well different types of CR, such as high-intensity interval training (HIIT), moderate-intensity continuous training (MICT), Nordic walking (NW), and home-based cardiac rehabilitation (HBCR), improve exercise capacity, quality of life, and lower death and illness rates. The objective is to assess the effectiveness of cardiovascular rehabilitation programs in enhancing clinical outcomes for patients diagnosed with CAD. A comprehensive literature search was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) model across Google Scholar, EMBASE, PubMed, Medline, and web browsers. Keywords such as "cardiac rehabilitation," "coronary artery disease," "exercise testing," "VO2 peak," and "physical activity" were used in different combinations. Studies were included if they were randomized controlled trials, observational studies, or longitudinal studies published after 2013 in English, with a focus on the impact of CR on CAD. Articles were excluded if they were reviews, meta-analyses, or did not meet the keyword requirements. A total of 375 articles were initially identified with relevant citations. After further screening, 10 studies met the inclusion criteria for analysis. The studies reviewed demonstrated that all forms of CR, including HIIT, MICT, NW, and HBCR, significantly improved exercise capacity and quality of life, and reduced depression severity among CAD patients. Nordic walking showed marked improvements in functional capacity, while HIIT resulted in higher VO2 peak levels compared to moderate-intensity exercise. Home-based CR showed greater adherence rates, especially among older patients and those with strong family support. The results also highlighted the importance of individualized exercise programs to enhance adherence and outcomes. Cardiac rehabilitation is a vital component of secondary prevention in CAD patients, significantly improving clinical outcomes, including exercise capacity, quality of life, and mortality rates. The findings underscore the importance of maintaining and expanding access to CR programs and tailoring interventions to patient needs to optimize long-term health outcomes. Future research should explore the comparative effectiveness of different CR modalities and strategies to increase patient adherence.

WITHDRAWN: Coronary atherosclerotic plaque regression strategies

Ahead of Print article withdrawn by publisher.

Exercise-based cardiac rehabilitation in stable angina pectoris: a narrative review on current evidence and underlying physiological mechanisms

Stable angina pectoris (SAP) is a prevalent condition characterised by a high disease burden. Based on recent evidence, the need for revascularisation in addition to optimal medical treatment to reduce mortality and re-events is heavily debated. These observations may be explained by the fact that revascularisation is targeted at the local flow-limiting coronary artery lesion, while the aetiology of SAP relates to the systemic, inflammatory process of atherosclerosis, causing generalised vascular dysfunction throughout the entire vascular system. Moreover, cardiovascular events are not solely caused by obstructive plaques but are also associated with plaque burden and high-risk plaque features. Therefore, to reduce the risk of cardiovascular events and angina, and thereby improve quality of life, alternative therapeutic approaches to revascularisation should be considered, preferably targeting the cardiovascular system as a whole with a physiological approach. Exercise-based cardiac rehabilitation fits this description and is a promising strategy as a first-line treatment in addition to optimal medical treatment. In this review, we discuss the role of exercise-based cardiac rehabilitation in SAP in relation to the underlying physiological mechanisms, we summarise the existing evidence and highlight future directions.

High intensity interval training induces beneficial effects on coronary atheromatous plaques - a randomized trial

BACKGROUND

Coronary atheroma volume is associated with risk of coronary events in coronary artery disease (CAD). Exercise training is a cornerstone in primary and secondary prevention of CAD, but the effect of exercise on coronary atheromatous plaques is largely unknown.

PURPOSE

We assessed the effect of six months supervised high intensity interval training (HIIT) on coronary plaque geometry using intravascular ultrasound in patients with stable CAD following percutaneous coronary intervention (PCI).

METHODS

Sixty patients were randomized to two sessions of weekly supervised HIIT at 85-95% of peak heart rate (n = 30) or to follow contemporary preventive guidelines (control group, n = 30). The study endpoints were change in percent atheroma volume (PAV) and total atheroma volume (TAV) normalized for segment length (TAVnorm) at six-month follow-up.

RESULTS

The change in average PAV for matched coronary segments from baseline to follow-up showed a significant between-group difference (-1.4, 95% CI: -2.7 to -0.1, p = 0.036). There was a significant reduction in the HIIT group (-1.2, 95% CI: -2.1 to -0.2, p = 0.017) while not in the control group (0.2, 95% CI: -0.7 to 1.1, p = 0.616). TAVnorm was reduced (-9 mm3, 95% CI: -14.7 to -3.4, p = 0.002) after HIIT, with a significant between-group difference (-12.0 mm3, 95% CI: -19.9 to -4.2, p = 0.003).

CONCLUSION

In patients with established CAD, a regression of atheroma volume was observed in those undergoing six months of supervised HIIT compared with patients following contemporary preventive guidelines. Our study indicates that high intensity interval training counteracts atherosclerotic coronary disease progression and reduces atheroma volume in residual coronary atheromatous plaques following PCI.

Effects of Phase II Cardiac Rehabilitation on Physical Function and Anxiety Levels in Frail Patients

Background: Frailty is an important prognostic factor in patients with cardiovascular diseases (CVD), and patients with CVD have a high rate of concurrent psycho-emotional stress, as well as depressive mood and anxiety symptoms. Despite this, few reports have examined the effects of the efficacy of Phase II cardiac rehabilitation (CR) in frail patients, including improvements in anxiety levels.

Methods and Results: In all, 137 patients (mean [±SD] age 65.8±13.0 years; 71% male) who participated in Phase II CR and were assessed after CR completion were included in this study. Patients were evaluated using the Kihon Checklist (KCL) form at the beginning of CR and were divided into the 3 groups according to KCL scores: frail (n=34, 25%), pre-frail (n=40, 29%), and non-frail (n=63, 46%). Physical function and anxiety levels were compared among the 3 groups. The pre-frail and frail groups had significantly higher state anxiety and trait anxiety than the non-frail group (P<0.01). At the end of Phase II CR, all 3 groups showed significant improvements in the 6-min walking distance (P<0.05). State anxiety improved significantly in the non-frail and pre-frail groups, whereas trait anxiety only improved in the non-frail group.

Conclusions: Physical function was improved in frail patients who participated in Phase II CR. However, there was no significant improvement in their level of anxiety.

Coronary Atherosclerotic Plaque Regression: JACC State-of-the-Art Review

Over the last 3 decades there have been substantial improvements in treatments aimed at reducing cardiovascular (CV) events. As these treatments have been developed, there have been parallel improvements in coronary imaging modalities that can assess plaque volumes and composition, using both invasive and noninvasive techniques. Plaque progression can be seen to precede CV events, and therefore, many studies have longitudinally assessed changes in plaque characteristics in response to various treatments, aiming to demonstrate plaque regression and improvements in high-risk features, with the rationale being that this will reduce CV events. In the past, decisions surrounding treatments for atherosclerosis have been informed by population-based risk scores for initiation in primary prevention and low-density lipoprotein cholesterol levels for titration in secondary prevention. If outcome data linking plaque regression to reduced CV events emerge, it may become possible to directly image plaque treatment response to guide management decisions.

Early cardiac rehabilitation: could it improve functional outcomes and reduce length of stay and sanitary costs in patients aged 75 years or older? A retrospective case-control study

BACKGROUND

Cardiac rehabilitation (CR) is considered as a cornerstone in improving physical function in older people after cardiac procedures; however, its effects in patients aged more than 75 years are still debated.

AIMS

To assess the effectiveness of early CR in improving functional outcomes and reducing the length of stay (LOS) and sanitary costs in patients aged ≥ 75 years.

METHODS

We retrospectively analysed data from medical records of patients aged ≥ 75 years performed CR after cardiac procedures. Patients were divided into two groups according to the median timing lasting from the cardiac procedure and CR start: 'early rehabilitation' (< 8 days) and 'delayed rehabilitation' (≥ 8 days). Six-minutes walking test (6MWT), left ventricular ejection fraction (LVEF), LOS, and sanitary costs were assessed.

RESULTS

The 160 patients (mean aged 79.18 ± 3.13 years) included were divided into two groups: 'early rehabilitation' (n = 80) and 'delayed rehabilitation' (n = 80). Both groups showed a significant improvement (p < 0.0001) in 6MWT and LVEF but there were no differences between groups in all clinical outcomes. On the other hand, the 'early rehabilitation' group showed significantly lower LOS (25.8 ± 5.3 vs 34.1 ± 10.8 days; p < 0.0001) and sanitary costs (22,282.08 ± 3242.68 euros vs. 44,954.03 ± 22,160.11 euros; p < 0.0001).

DISCUSSION

Beginning CR in the first week seems to be effective in improving physical performance after cardiac procedures in patients aged ≥ 75 years, reducing LOS and sanitary costs.

CONCLUSIONS

Our findings suggest that early CR could be performed with positive effects on functional outcomes, leading to a reduction in LOS and sanitary costs in elderly.

Arterial Stiffness Index and Exercise Tolerance in Patients Undergoing Cardiac Rehabilitation

Arterial stiffness contributes to the development of cardiovascular disease (CVD). However, the relationship between the arterial stiffness and exercise tolerance in CVD patients with preserved ejection fraction (pEF) and those with reduced EF (rEF) is unclear. We enrolled 358 patients who participated in cardiac rehabilitation and underwent cardiopulmonary exercise testing at Juntendo University Hospital. After excluding 195 patients who had undergone open heart surgery and 20 patients with mid-range EF, the patients were divided into pEF (n = 99) and rEF (n = 44) groups. Arterial stiffness was assessed using arterial velocity pulse index (AVI) and arterial pressure volume index (API) at rest. The patients in the pEF group were significantly older and had a higher prevalence of coronary artery disease than the rEF group. The pEF group had significantly lower AVI levels and higher API levels than the rEF group. In the pEF group, the peak oxygen uptake (peak VO₂) and the anaerobic threshold was significantly higher than those in the rEF group. The peak VO₂ was significantly and negatively correlated with AVI and API in the pEF group (All, P < 0.05), but not in the rEF group. Multivariate linear regression analyses demonstrated that AVI was independently associated with peak VO₂ (β = -0.34, P < 0.05) in the pEF group. In conclusion, AVI may be a useful factor for assessing exercise tolerance, particularly in CVD patients with pEF.

Relationship Between Kihon Checklist Score and Anxiety Levels in Elderly Patients Undergoing Early Phase II Cardiac Rehabilitation

Background

The frailty state consists of not only physical but also psycho-emotional problems, such as cognitive dysfunction and depression as well as social problems. However, few reports have examined the relationship between frailty and anxiety levels in elderly patients undergoing cardiac rehabilitation (CR).

Methods

We analyzed 255 patients (mean age: 74.9 ± 5.8 years, 67% male) who participated in early phase II CR at Juntendo University Hospital. At the beginning of CR, patients carried out self-assessments based on the Kihon Checklist (KCL) and the State Trait Anxiety Inventory Form (STAI). Patients were divided into three groups: frailty group (n = 99, 39%), pre-frailty group (n = 81, 32%), and non-frailty group (n = 75, 29%) according to the KCL. We assessed results from the KCL scores and its relationship with anxiety levels.

Results

Among the three groups, there were no significant differences in age, underlying illnesses, or the prevalence of coronary risk factors. Depressive mood domains of the KCL were significantly higher in the frailty and pre-frailty groups than in the non-frailty groups (3.0 ± 1.5 vs. 1.4 ± 1.2 vs. 0.4 ± 0.6; P < 0.01). The state anxiety level was significantly higher in the frailty group than in the non-frailty group (41.6 ± 0.9 vs. 34.9 ± 1.0; P < 0.01). The trait anxiety levels were significantly higher in the frailty group and pre-frailty group than in the non-frailty group (45.5 ± 0.9 vs. 39.2 ± 1.0 vs. 35.1 ± 1.1; P < 0.01). State anxiety and trait anxiety also showed a significantly positive correlations with the KCL scores (r = 0.32 vs. 0.41, P < 0.01).

Conclusions

Frailty scores were positively correlated not only with physical function but also with depression mood and anxiety levels in elderly patients undergoing early phase II CR. These results suggest that assessment of depressive mood and anxiety is also important in elderly patients undergoing early phase II CR.

Preliminary Pilot Study of Combined Effects of Physical Activity and Achievement of LDL-Cholesterol Target on Coronary Plaque Volume Changes in Patients with Acute Coronary Syndrome

BACKGROUND

We investigated the combined effects of physical activity (PA) and aggressive low-density lipoprotein cholesterol (LDL-C) reduction on the changes in coronary plaque volume (PV) in patients with acute coronary syndrome (ACS) using volumetric intravascular ultrasound (IVUS) analysis.

METHODS

We retrospectively analyzed data from two different prospective clinical trials that involved 101 ACS patients who underwent percutaneous coronary intervention (PCI) and assessed the non-culprit sites of PCI lesions using IVUS at baseline and at the follow-up. After PCI, all the patients participated in early phase II comprehensive cardiac rehabilitation. Patients were divided into four groups based on whether the average daily step count, measured using a pedometer, was 7000 steps of more and whether the follow-up LDL-C level was <70 mg/dL. At the time of follow-up, we examined the correlation of changes in the PV with LDL-C and PA.

RESULTS

The baseline characteristics of the four study groups were comparable. At the follow-up, plaque regression in both the achievement group (PA and LDL-C reduction) was higher than that in the other three groups. In addition, plaque reduction independently correlated with increased PA and reduction in LDL-C level.

CONCLUSIONS

Combined therapy of intensive PA and achievement of LDL-C target retarded coronary PV in patients with ACS.

Association between the tissue accumulation of advanced glycation end products and exercise capacity in cardiac rehabilitation patients

Background

Advanced glycation end products (AGEs) are associated with aging, diabetes mellitus (DM), and other chronic diseases. Recently, the accumulation of AGEs can be evaluated by skin autofluorescence (SAF). However, the relationship between SAF levels and exercise capacity in patients with cardiovascular disease (CVD) remains unclear. This study aimed to investigate the association between the tissue accumulation of AGEs and clinical characteristics, including exercise capacity, in patients with CVD.

Methods

We enrolled 319 consecutive CVD patients aged ≥40 years who underwent early phase II cardiac rehabilitation (CR) at our university hospital between November 2015 and September 2017. Patient background, clinical data, and the accumulation of AGEs assessed by SAF were recorded at the beginning of CR. Characteristics were compared between two patient groups divided according to the median SAF level (High SAF and Low SAF).

Results

The High SAF group was significantly older and exhibited a higher prevalence of DM than the Low SAF group. The sex ratio did not differ between the two groups. AGE levels showed significant negative correlations with peak oxygen uptake and ventilator efficiency (both P <  0.0001). Exercise capacity was significantly lower in the high SAF group than in the low SAF group, regardless of the presence or absence of DM (P <  0.05). A multivariate logistic regression analysis showed that SAF level was an independent factor associated with reduced exercise capacity (odds ratio 2.10; 95% confidence interval 1.13–4.05; P = 0.02).

Conclusion

High levels of tissue accumulated AGEs, as assessed by SAF, were significantly and independently associated with reduced exercise capacity. These data suggest that measuring the tissue accumulation of AGEs may be useful in patients who have undergone CR, irrespective of whether they have DM.