Association between asymmetric dimethylarginine and in-stent restenosis tissue characteristics assessed by optical coherence tomography

Naturally Occurring Atherosclerosis Progression and In-stent Restenosis: Exploring Histomorphologic Associations Using Optical Coherence Tomography

ABSTRACT

The mechanism of in-stent restenosis (ISR) remains elusive, and in-stent neoatherosclerosis (ISNA) may hold significant pathophysiologic implications. Nevertheless, the correlation between ISNA and the progression of untreated coronary segments affected by native atherosclerosis remains incompletely investigated. This study enrolled 225 patients diagnosed with coronary heart disease and multivessel disease. These patients underwent successful percutaneous coronary intervention and intraoperative placement of the drug-eluting stent, followed by optical coherence tomography assessment of the culprit stent. The mechanism of ISR was examined through qualitative and quantitative analysis of optical coherence tomography imaging. A significantly higher proportion of patients in the ISR with nontarget lesion progression (N-TLP) group exhibited lipid plaque formation compared with the ISR without N-TLP group (69.0% vs. 39.8%, P < 0.001). The incidence of thin-cap fibroatheroma (33.3% vs. 11.4%, P = 0.001) and ISNA (60.7% vs. 38.6%, P < 0.001) was markedly elevated in the ISR with N-TLP group compared with the ISR without N-TLP group. Regarding manifestations, heterogeneous hyperplasia was predominantly observed in the ISR with N-TLP group (76.2% vs. 38.6%, P < 0.001), whereas homogeneous hyperplasia was primarily presented in the ISR without N-TLP group (61.4% vs. 23.8%, P < 0.001). Patients displaying notable progression of naturally occurring atherosclerosis manifest histomorphologic features of ISR, primarily characterized by heterogeneous intimal hyperplasia and a higher prevalence of ISNA. In contrast, patients without substantial progression of naturally occurring atherosclerosis exhibit histomorphologic features of ISR primarily characterized by homogeneous intimal hyperplasia.

Optical Coherence Tomography Findings in Patients Presenting With In-Stent Restenosis: A Prospective Observational Study of Patterns of Neointimal Hyperplasia and Associated Risk Factors

Introduction Morphological features of neointimal tissue play a pivotal role in the pathophysiology of in-stent restenosis (ISR) after percutaneous coronary intervention (PCI). This study was designed to qualitatively and quantitatively assess neointimal characteristics of lesions using optical coherence tomography (OCT) in patients presenting with ISR.  Methods This was a single-center, prospective, observational study performed at a tertiary-care center in India. Patients diagnosed with stable angina and acute coronary syndrome with post-procedural angiographically documented restenosis (>50%) were included. Results A total of 34 patients with ISR were studied. Neointimal hyperplasia was classified as (i) homogenous group (n = 18) and (ii) non-homogenous group (n = 16). Fourteen (77.8%) diabetics belonged to the homogenous group. Predominant plaque characteristics such as neoatherosclerosis, cholesterol crystals, and calcium were documented in 14 (77.8%), 12 (66.7%), and 11 (61.1%) patients in the homogenous group and 10 (62.5%), 10 (62.5%), and 9 (56.2%) patients in the non-homogenous group, respectively. Unexpanded stent struts were identified in 11 (61.1%) and 11 (68.8%) patients in the homogenous and non-homogenous groups, respectively. Mean strut thickness was 93.73 ± 31.03 µm and 83.54 ± 18.0 µm, ISR was 72.50 ± 15.93% and 65.37 ± 21.69%, the neointimal thickness was 588.06 ± 167.82 μm and 666.25 ± 218.05 μm, and neointimal hyperplasia was 54.54 ± 11.23% and 59.26 ± 8.86% in the homogenous and non-homogenous groups, respectively. Conclusion Neoatherosclerosis and stent underexpansion were predominantly observed in our study and only diabetes was found to be significantly associated with homogenous neointimal hyperplasia.

Plasma asymmetric dimethylarginine is associated with vulnerable plaque and long-term outcomes in stable coronary artery disease

Asymmetric dimethylarginine (ADMA) is considered to be an atherogenic molecule. We aimed to investigate the relationship between ADMA and plaque vulnerability assessed by optical coherence tomography (OCT) in patients with stable coronary artery disease (CAD). Two hundred and forty-five patients with stable CAD undergoing OCT-guided percutaneous coronary intervention were included in this study and were divided into two groups according to their ADMA levels. Micro-vessel, macrophage accumulation, thin-cap fibroatheroma, intra-plaque calcium and lipid core content, and vulnerable score (VS) were evaluated by OCT analysis. The patients with higher ADMA levels had significantly higher calcium and lipid content (p < 0.001, respectively). There were significantly more micro-vessel and macrophage (32.8%, p = 0.004 and 52.5%, p < 0.001, respectively) and higher VS (87.7 ± 17.6, p < 0.001) in the higher ADMA group. Moreover, plasma ADMA level was significantly correlated with the intra-plaque lipid, calcium content and VS (p < 0.001, respectively). Plasma ADMA level was identified as an independent predictor of future adverse cardiovascular events, following OCT-guided PCI. In patients with stable CAD, higher plasma ADMA levels were significantly associated with the presence of intra-plaque lipid, calcification, vulnerable plaque, and poor long-term outcomes.

Asymmetric Dimethylarginine as a Biomarker in Coronary Artery Disease

As atherosclerosis remains a leading cause of morbidity and mortality worldwide despite the advances in its medical and interventional management, the identification of markers associated with its incidence and prognosis constitutes an appealing prospect. In this regard, asymmetric dimethylarginine (ADMA), a well-studied endogenous endothelial nitric oxide synthase inhibitor, represents a core mediator of endothelial dysfunction in atherosclerotic diseases. Given the pathophysiologic background of this molecule, its importance in the most frequent atherosclerotic manifestation, coronary artery disease (CAD), has been extensively studied in the past decades. The available evidence suggests elevation of ADMA in the presence of common cardiovascular risk factors, namely diabetes mellitus, arterial hypertension, and hypertriglyceridemia, being related to endothelial dysfunction and incident major adverse cardiovascular events in these groups of patients. Moreover, ADMA is associated with CAD occurrence and severity, as well as its prognosis, especially in populations with renal impairment. Interestingly, even in the absence of obstructive CAD, increased ADMA may indicate coronary endothelial dysfunction and epicardial vasomotor dysfunction, which are prognostication markers for incident cardiovascular events. In the case of acute coronary syndromes, high ADMA levels signify an augmented risk of incomplete ST-segment elevation resolution and poorer prognosis. Abnormal ADMA elevations may indicate adverse outcomes following percutaneous or surgical coronary revascularization, such as in-stent restenosis, graft patency, and hard cardiovascular endpoints. Finally, since its association with inflammation is significant, chronic inflammatory conditions may present with coronary endothelial dysfunction and subclinical coronary atherosclerosis by means of increased coronary artery calcium, with augmented ADMA acting as a biomarker.

Autoimmune diseases in patients undergoing percutaneous coronary intervention: A risk factor for in-stent restenosis?

BACKGROUND AND AIMS

Despite the relation between autoimmune diseases and increased atherosclerotic risk is established, the influence of autoimmune disorders on in-stent restenosis (ISR) after percutaneous coronary intervention (PCI) is only partly known. ISR is an aberrant reparative process mainly characterized by an increased number of vascular smooth muscle cells and excessive deposition of extracellular proteoglycans and type III collagen. Chronic inflammation, always present in autoimmune diseases, modulates the endothelial response to PCI. Aim of this review is to resume the current evidence on the association between ISR and autoimmune diseases, focusing on pathogenic mechanisms and therapeutic targets.

METHODS

We conducted a comprehensive review of the literature on the relationship between ISR and insulin-dependent diabetes mellitus (IDDM), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), antiphospholipid-antibodies syndrome (APS), inflammatory bowel diseases (IBD), and Hashimoto's thyroiditis (HT).

RESULTS

Patients affected with IDDM, RA, SLE, APS, IBD and HT proved to face higher rates of ISR compared to the general population. The endothelial dysfunction seems the principal common pathogenic pathway for ISR and is attributed to both the immune system disorder and the systemic inflammation. Some evidence suggested that methotrexate and anti-tumor necrosis factor treatments can be effective in reducing ISR, while antibodies against vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 showed to reduce neointimal hyperplasia in animal models.

CONCLUSIONS

Autoimmune diseases are a risk factor for ISR. The study of the potential cardiovascular benefits of the current therapies, mainly anti-inflammatory drugs, and the pursuit of innovative treatments appear of paramount interest.

Potential Mechanisms of In-stent Neointimal Atherosclerotic Plaque Formation

ABSTRACT

Percutaneous coronary intervention has become the main revascularization strategy for coronary artery disease. Compared with early percutaneous coronary angioplasty and the extensive clinical application of bare metal stents, drug-eluting stents can significantly reduce the stenosis caused by the elastic retraction of plaque and neoatherosclerosis (NA), but there is still a high incidence of in-stent restenosis (ISR), which restricts the clinical efficacy of stent implantation. In-stent neoatherosclerosis (ISNA), defined as atherosclerotic lesions in the neointima, is one of the main causes of late stent failure. ISNA plays an important role in stent thrombosis and ISR. The rate of target lesion revascularization and in-stent thrombosis is high when NA arises. Therefore, it is of great clinical significance to explore the occurrence of NA and its development mechanism after stent implantation to prevent ISR and improve stent implantation efficacy and associated clinical prognosis. In this article, we systematically reviewed the existing clinical research on ISNA and the role of optical coherence tomography in its evaluation.

Asymmetric dimethylarginine level as biomarkers of cardiovascular or all-cause mortality in patients with chronic kidney disease: a meta-analysis

BACKGROUND

Studies have yielded conflicting findings on the association of asymmetric dimethylarginine (ADMA) level with cardiovascular or all-cause mortality in patients with chronic kidney disease (CKD). This meta-analysis sought to evaluate the association of blood ADMA level with cardiovascular or all-cause mortality in CKD patients.

MATERIALS AND METHODS

PubMed and Embase databases were comprehensively searched until September 9, 2020 for studies investigating the association of ADMA level with cardiovascular or all-cause mortality in CKD patients.

RESULTS

Data were collected from nine prospective studies involving 6553 patients. The pooled adjusted risk ratio (RR) of all-cause mortality was 2.06 (95% confidence interval [CI] 1.43-2.96) for the highest versus the lowest ADMA level. Each 0.20 μmol/L ADMA increase was associated with 21% (95% CI 1.09-1.35) higher risk of all-cause mortality but not cardiovascular mortality (RR 1.07; 95% CI 0. 99-1.16). Subgroup analysis showed that each 0.20 μmol/L ADMA increase was significantly associated with all-cause mortality in end-stage renal disease (ESRD) patients (RR 1.22; 95% CI 1.05-1.41) but not in patients with stage 3 to 4 CKD (RR 1.16; 95% CI 0.86-1.56).

CONCLUSIONS

Elevated ADMA level is independently associated with higher risk of all-cause mortality in ESRD patients.

Elevated asymmetric dimethylarginine level as biomarkers of adverse outcomes in individuals undergoing coronary angiography/percutaneous coronary interventions: a systematic review and meta-analysis

BACKGROUND

No previous systematic review and meta-analysis have comprehensively evaluated the association of asymmetric dimethylarginine (ADMA) level with adverse prognosis in individuals undergoing percutaneous coronary interventions (PCI)/coronary angiography (CAG). The aim of this systematic review and meta-analysis was to assess the predictive value of the elevated ADMA level in individuals undergoing CAG/PCI.

MATERIALS AND METHODS

Two authors independently searched PubMed and Embase databases (up to 31 October 2020) for observational studies investigating the association between circulating ADMA level and adverse outcomes in individuals undergoing CAG/PCI. The predictive value of ADMA was expressed by pooling the multivariable-adjusted risk ratio with 95% confidence intervals (CI) for the highest versus lowest ADMA level.

RESULTS

A total of nine prospective studies with 6374 participants were identified. Compared with those with the lowest ADMA level, patients with the highest ADMA level conferred an increased risk of all-cause mortality (risk ratio, 2.11; 95% CI, 1.38-3.21), cardiovascular mortality (risk ratio, 2.95; 95% CI, 1.14-7.68), major adverse cardiovascular events (risk ratio, 2.10; 95% CI, 1.35-3.27) and restenosis (risk ratio, 4.57; 95% CI, 2.52-8.30), respectively.

CONCLUSIONS

High level of ADMA level is possibly an independent predictor of mortality and cardiovascular events in individuals undergoing CAG/PCI. Detection of blood ADMA level before CAG/PCI may add valuable clinical prognosis information.

Prognostic value of asymmetric dimethylarginine in patients with coronary artery disease: A meta-analysis

BACKGROUND

Studies regarding the predictive utility of the blood level of asymmetric dimethylarginine (ADMA) in patients with coronary artery disease (CAD) have yielded the conflicting findings. This meta-analysis sought to evaluate the prognostic value of blood ADMA level in CAD patients.

METHODS

Potentially relevant studies were identified by searching PubMed and Embase database until August 12, 2020. Cohort studies evaluating the association of blood ADMA level with all-cause mortality, cardiovascular mortality, and major adverse cardiovascular events (MACEs) were included. A random effect model was applied to pool the multivariable-adjusted risk ratio (RR) and 95% confidence intervals (CI) for the highest versus lowest ADMA level.

RESULTS

Data were retrieved from 11 studies enrolling a total of 9496 CAD patients. When compared the highest to the lowest ADMA level, the pooled RR was 2.10 (95% CI 1.46-3.02) for all-cause mortality, 2.49 (95% CI 1.34-4.65) for cardiovascular mortality, and 1.71 (95% CI 1.27-2.32) for MACEs, respectively. However, subgroup analysis showed that there were no significant association between elevated ADMA level and all-cause mortality in acute coronary syndrome (RR 2.11; 95% CI 0.93-4.78) and follow up ≤ 1 year (RR 2.15; 95% CI 0.56-8.25) subgroup.

CONCLUSIONS

Elevated blood ADMA level is possibly an independent predictor of all-cause mortality, cardiovascular mortality, and MACEs in CAD patients. Measurement of blood level of ADMA may improve risk classification of CAD. However, these findings should be interpreted with caution because of the limited number of studies included.

The characteristics and risk factors of in-stent restenosis in patients with percutaneous coronary intervention: what can we do

BACKGROUND

Percutaneous coronary intervention (PCI) is a common treatment for patients with coronary heart disease, and intra-stent restenosis (ISR) is a serious complication after PCI. It's necessary to identify the potential risk factors to provide evidence for the prevention of ISR.

METHODS

The patients who underwent coronary angiography 1 year after PCI in our hospital from January 2017 to May 2019 were selected. The characteristics and results of clinical examination of ISR and no-ISR patients were compared, Multivariate logistic regression analyses were performed to identify the risk factors.

RESULTS

A total of 209 patients were included, the incidence of ISR after PCI was 30.62%. There were significant differences on the hypertension, diabetes, number of coronary artery lesions, reasons for stent implantation, the diameter of stent, the length of stent and stent position between ISR group and no-ISR patients (all p < 0.05). The LDL-C in ISR groups was significantly higher than that of no-ISR group (p = 0.048), there were no significant differences between two groups in FPG, TG, TC, HDL-C, Apo A1, Apo B, LP-a and glycated haemoglobin (all p > 0.05). The hypertension (OR 4.30, 95% CI 1.12-9.34), diabetes (OR 5.29, 95% CI 1.25-9.01), number of coronary artery lesions ≥ 2 (OR 4.84, 95% CI 1.21-9.55), LDL-C ≥ 1.9 mmol/L (OR 5.93, 95% CI 2.29-10.01), unstable angina (OR 2.92, 95% CI 1.20-4.55), left anterior descending artery (OR 4.01, 95% CI 1.73-7.58), diameter of stent ≥ 3 mm (OR 5.42, 95% CI 1.24-10.84), the length of stent > 20 mm (OR 3.06, 95% CI 1.19-5.22) were the independent risk factor for ISR (all p < 0.05).

CONCLUSION

It is necessary to take preventive measures against these risk factors to reduce ISR, and studies with larger sample size and longer follow-up on this issue are needed in the future.

ADMA: A Key Player in the Relationship between Vascular Dysfunction and Inflammation in Atherosclerosis

Atherosclerosis is a chronic cardiovascular disease which increases risk of major cardiovascular events including myocardial infarction and stroke. Elevated plasma concentrations of asymmetric dimethylarginine (ADMA) have long been recognised as a hallmark of cardiovascular disease and are associated with cardiovascular risk factors including hypertension, obesity and hypertriglyceridemia. In this review, we discuss the clinical literature that link ADMA concentrations to increased risk of the development of atherosclerosis. The formation of atherosclerotic lesions relies on the interplay between vascular dysfunction, leading to endothelial activation and the accumulation of inflammatory cells, particularly macrophages, within the vessel wall. Here, we review the mechanisms through which elevated ADMA contributes to endothelial dysfunction, activation and reactive oxygen species (ROS) production; how ADMA may affect vascular smooth muscle phenotype; and finally whether ADMA plays a regulatory role in the inflammatory processes occurring within the vessel wall.