Prevalence Of In-stent Restenosis Research Articles

Successful treatment of chronic venous in-stent restenosis using a Phoenix atherectomy device.

Although endovascular treatment of venous obstruction with percutaneous transluminal angioplasty (PTA) and stenting is a safe and effective alternative to conservative treatment, the overall prevalence of in-stent restenosis (ISR) remains high in this patient population. This study reports a novel treatment option for patients with chronic ISR (C-ISR). At our center, all patients with ISR were treated based on the time since the initial intervention. Acute in-stent restenosis (A-ISR) was preferably treated with catheter-directed thrombolysis or a pharmacomechanical peripheral thrombectomy device and PTA. Selected patients with chronic ISR (C-ISR) (greater than 30 days) were treated with a catheter- guided unidirectional atherectomy in addition to PTA, under the assumption of a non-thrombotic mechanism in the development of C-ISR. We demonstrate a safe and practical treatment option for chronic ISR using a catheter- guided technical approach with the Phoenix atherectomy device in four patients. Technical success was achieved in every case, and mid-term patency was restored in three out of four patients. Restenosis following venous stenting is highly complex. Patients must be treated individually, with a focus on anticoagulation and antiplatelet therapy regimens, as well as the appropriate interventional treatment. Catheter- guided atherectomy is a viable option for this heterogeneous group of patients. Further studies are required to understand the etiology of chronic ISR.

Prevalence and predictors of coronary artery stent re-stenosis in patients with cancer with prior history of percutaneous coronary intervention: A nationwide analysis.

e24018 Background: Data regarding the prevalence, and predictors of development of in-stent restenosis (ISR) in cancer patients undergoing percutaneous coronary intervention (PCI) are scarce. This study aimed to identify factors associated with the development of ISR following PCI in cancer patients. Methods: This is a retrospective cohort study using the National Inpatient Sample(NIS) from 2016 to 2020. Discharges with ICD-10 CM code indicating stenosis of coronary artery stent, and secondary ICD-10 CM code indicating cancer, and prior history of PCI were included. Primary outcome was development of ISR. Multivariate logistic regression model was used to identify predictors of ISR development, and p value of less than 0.05 was considered significant. Results: There were 873,320 patients who met inclusion criteria, among which 4060 patients were admitted for coronary stent re-stenosis. Mean age of included patients was 73, and 31% were females. The prevalence rate of in-stent restenosis was 0.46%. Factors associated with increased odds of development of ISR included diabetes (OR 1.31, 95% CI 1.13-1.51, p < 0.001), dyslipidemia (OR 1.92, 95% CI 1.60-2.31, p < 0.001), congestive heart failure (OR 1.78, 95% CI 1.52-2.06, p < 0.01), carotid disease (OR 1.99, 95% CI 1.43-2.78, p < 0.001), and aortic disease (OR 1.83, 95% CI 1.12-2.98, p 0.01). Age, gender, race, median household income, hospital location and hospital teaching status didn’t exhibit statistically significant increased risk. Conclusions: The prevalence of in-stent restenosis was 0.46%. Appropriate management of risk factors such as diabetes, dyslipidaemia, congestive heart failure is prudent to prevent development of ISR in cancer patients, underscoring the importance of regular cardiology follow up, along with routine cancer care.

Prevalence of In-Stent Restenosis in Patients having Drug Eluting Stents with Lengths Exceeding 40mm: A Single-Center Study

Background: Coronary artery disease (CAD) remains a significant global health challenge, with percutaneous coronary intervention (PCI) being a primary treatment method. The use of long drug-eluting stents (DES) has been linked to varied outcomes, particularly concerning in-stent restenosis (ISR), which may be influenced by factors like stent length and patient comorbidities. Objective: To assess the prevalence of ISR in patients undergoing PCI with long DES (>40mm), considering patient demographics, comorbidities, and lesion characteristics. Methods: This cross-sectional study was conducted at Frontier Corps Teaching Hospital (FCTH) and Lady Reading Hospital in Peshawar, Pakistan, involving 102 patients. The study focused on the frequency of ISR post-angioplasty, particularly in relation to comorbid conditions such as diabetes and hypertension. Data collection included demographics, echocardiographic assessments, and detailed angiogram analysis. Statistical analysis was performed using SPSS version 23.0, with a significance threshold set at p<0.05. Results: The overall prevalence of ISR was found to be 18.63%. Diabetes and hypertension showed a significant association with ISR, with p-values <0.0015. The ISR frequencies for single vessel disease (SVCAD), double vessel disease (DVCAD), and triple vessel disease (TVCAD) were 26.32%, 31.58%, and 42.10%, respectively, with TVCAD showing a statistically significant association (p=0.0185). Conclusion: The study highlights a significant association between long DES and increased ISR rates, particularly in patients with complex coronary anatomies and multiple comorbidities. Shorter stents are recommended to potentially reduce restenosis and improve outcomes in CAD management.

The Predictive Value of the Perivascular Adipose Tissue CT Fat Attenuation Index for Coronary In-stent Restenosis.

ObjectivesTo investigate the association between the perivascular adipose tissue (PVAT) fat attenuation index (FAI) derived from coronary computed tomography angiography (CCTA) and the prevalence of in-stent restenosis (ISR) in patients with coronary stent implantation.MethodsA total of 117 patients with previous coronary stenting referred for invasive coronary angiography (ICA) were enrolled in this retrospective observational analysis. All patients underwent CCTA between July 2016 and November 2021. The deep learning-based (DL-based) method was used to analyze and measure the peri-stent FAI value. Additionally, the relationship between hematological and biochemical parameters collected from all the patients was also explored. The least absolute shrinkage and selection operator (LASSO) method was applied to the most useful feature selection, and binary logistic regression was used to test the association between the selected features and ISR. The predictive performance for ISR of the identified subgroups was evaluated by calculating the area under the curve (AUC) of receiver operator curves plotted for each model. The Pearson correlation coefficient was used to assess the correlation of peri-stent FAI values with degrees of ISR.ResultsThe peri-stent FAI values in the ISR group were significantly higher than those in the non-ISR group (−78.1 ± 6.2 HU vs. −87.2 ± 7.3 HU, p < 0.001). The predictive ISR features based on the LASSO analysis were peri-stent FAI, high-density lipoprotein cholesterol (HDL-C), apolipoprotein A1 (ApoA1), and high-sensitivity c-reactive protein (hs-CRP), with an AUC of 0.849, 0.632, 0.620, and 0.569, respectively. Binary logistic regression analysis determined that peri-stent FAI was uniquely and independently associated with ISR after adjusting for other risk factors (odds ratio [OR] 1.403; 95% CI: 1.211 to 1.625; p < 0.001). In the subgroup analysis, the AUCs of the left anterior descending coronary artery (LAD), left circumflex coronary artery (LCx), and right coronary artery (RCA) stents groups were 0.80, 0.87, and 0.96, respectively. The Pearson's correlation coefficient indicated a term moderately correlation between ISR severity and peri-stent FAI values (r = 0.579, P < 0.001).ConclusionsThe peri-stent FAI can be used as an independently non-invasive biomarker to predict ISR risk and severity after stent implantation.

CYP2C19 polymorphism and coronary in-stent restenosis: A systematic review and meta-analysis

Background: In-stent restenosis (ISR) remains a major drawback in coronary stenting. The association between the CYP2C19 loss of function (LOF) gene and the prevalence of ISR after coronary stenting remains controversial. Previous studies have produced conflicting results and have been limited by their small population sizes. We conducted this systematic review and meta-analysis to determine the association between the presence of the CYP2C19 LOF gene and the prevalence of ISR. Methods: A systematic online database search was performed until April 2021. The primary outcome was ISR and assessed using OR with 95% CI. Publication bias was assessed using the Newcastle Ottawa Scale. I2 was applied to examine heterogeneities among the studies. Results: A total of 284 patients (four non-randomized controlled trial studies) were included in this study. Two hundred and six patients had wild-type genotypes, while 78 patients had the LOF genotype. Among the 78 patients with the LOF gene, 40 patients had an ISR. Meanwhile, of the 206 patients with a wild-type gene, 69 patients had an ISR. The LOF gene was associated with a higher risk of ISR (OR 95% CI = 2.84 [1.54–5.24], p = 0.0008). A major limitation in our study was the small number of previous studies and small sample sizes. Conclusions: Patients with LOF genes, regardless of the allele variation, treated with clopidogrel, had a higher risk of developing ISR after coronary stenting.

Restenosis of Drug-Eluting Stents: A New Classification System Based on Disease Mechanism to Guide Treatment and State-of-the-Art Review.

Despite on-going evolution and iteration of drug-eluting stent (DES) technology, the prevalence of in-stent restenosis (ISR) remains relatively unchanged, encompassing ≈10% of percutaneous coronary interventions. The mechanism of ISR is multifactorial, including biological, mechanical, patient, and operator-related factors. The main mechanical contributors are stent underexpansion or fracture, while biological factors include local inflammation leading to aggressive neointimal proliferation and late neoatherosclerosis. Intracoronary imaging is critical to identify the mechanism of ISR and tailor therapy accordingly. The presentation of DES-ISR is not benign and is challenging for optimal treatment. Among the proposed treatment modalities are scoring and high-pressure balloons, percutaneous coronary intervention with additional DES, atheroablative therapies by laser or mechanical atherectomy, drug-coated balloons, vascular brachytherapy, and surgical revascularization. We propose a new classification for ISR that differentiates among mechanical, biological, and mixed etiologies. Stratifying ISR by mechanism guides individualized treatment of DES-ISR to improve clinical outcomes. An algorithmic approach, guided by intracoronary imaging, for the treatment of DES-ISR, is recommended based on the specific cause of restenosis.

Eluting combination drugs from stents

Cardiovascular diseases (CVD) are one of the leading causes of death across the globe. Pathogenesis of coronary artery disease (CAD) is lead by the progression of atherosclerotic lacerations in coronary arteries. Percutaneous coronary intervention (PCI) using balloon angioplasty was introduced in 1979 and was majorly used in the treatment of these lesions. Introduction of bare metal stents (BMS) has revolutionized stenting procedures overcoming elastic recoil and reducing restenosis commonly associated with balloon angioplasty, but follow up studies have shown 20-30% prevalence of in-stent restenosis (ISR), this led to the development of drug eluting stents (DES). But long-term follow up studies have shown increased liability of stent thrombosis. Boosting the development of safer and effective DES expounding for therapies like biodegradable polymer based DES, polymer free DES, bioresorbable DES and combination DES to collectively reduce neointimal hyperplasia and promote endothelial healing. In dual-DES development, a combination employing an anti-restenotic agent (for preventing VSMC's proliferation), which is released for the first few weeks, and then the second drug a pro-healing agent (promoting re-endothelialization) released after a month would be ideal. Growing understanding in the areas of polymer therapeutics, nanoscale surface modifications and gene therapy would assist in the delivery of multiple drugs, which would further help in the design of promising therapeutic strategies for the treatment of CAD using stent based therapies.

High diagnostic accuracy of prospective ECG-gating 64-slice computed tomography coronary angiography for the detection of in-stent restenosis

The accuracy of computed tomography (CT) for assessment of coronary stents is as yet unproven and radiation exposure has been a concern. The aim of our study is to compare radiation dose and diagnostic performance of CT with prospective ECG-triggering versus retrospective ECG-triggering for the detection of in-stent restenosis (ISR). We enrolled 168 consecutive patients with suspected ISR, 83 studied using CT with prospective ECG-triggering (group 1) and 85 using retrospective ECG-triggering (group 2). Prevalence of ISR according to catheter angiography was 24% in both groups. The overall evaluability was similar (93% in group 1 vs 95% in group 2). Artefact sub-analysis showed a significantly lower number of blooming and higher number of slice misalignment in group 1 vs group 2. In the stent-based analysis using only evaluable stents, specificity, positive predictive value and accuracy were significantly higher in group 1 (100%, 100% and 99%, respectively) than in group 2 (97%, 91% and 95%, respectively, p < 0.05). Group 1 was exposed to a lower radiation dose compared with group 2 (4.3 ± 1.4mSv vs 18.5 ± 5.5mSv, p < 00.1). CT with prospective ECG-triggering can improve diagnostic accuracy of non-invasive imaging of coronary stents with a significant reduction in radiation exposure.

Assessment of In-Stent Restenosis Using 64-MDCT: Analysis of the CORE-64 Multicenter International Trial

Evaluations of stents by MDCT from studies performed at single centers have yielded variable results with a high proportion of unassessable stents. The purpose of this study was to evaluate the accuracy of 64-MDCT angiography (MDCTA) in identifying in-stent restenosis in a multicenter trial. The Coronary Evaluation Using Multidetector Spiral Computed Tomography Angiography Using 64 Detectors (CORE-64) Multicenter Trial and Registry evaluated the accuracy of 64-MDCTA in assessing 405 patients referred for coronary angiography. A total of 75 stents in 52 patients were assessed: 48 of 75 stents (64%) in 36 of 52 patients (69%) could be evaluated. The prevalence of in-stent restenosis by quantitative coronary angiography (QCA) in this subgroup was 23% (17/75). Eighty percent of the stents were <or=3.0 mm in diameter. The overall sensitivity, specificity, positive predictive value, and negative predictive value to detect 50% in-stent stenosis visually using MDCT compared with QCA was 33.3%, 91.7%, 57.1%, and 80.5%, respectively, with an overall accuracy of 77.1% for the 48 assessable stents. The ability to evaluate stents on MDCTA varied by stent type: Thick-strut stents such as Bx Velocity were assessable in 50% of the cases; Cypher, 62.5% of the cases; and thinner-strut stents such as Taxus, 75% of the cases. We performed quantitative assessment of in-stent contrast attenuation in Hounsfield units and correlated that value with the quantitative percentage of stenosis by QCA. The correlation coefficient between the average attenuation decrease and >or=50% stenosis by QCA was 0.25 (p=0.073). Quantitative assessment failed to improve the accuracy of MDCT over qualitative assessment. The results of our study showed that 64-MDCT has poor ability to detect in-stent restenosis in small-diameter stents. Evaluability and negative predictive value were better in large-diameter stents. Thus, 64-MDCT may be appropriate for stent assessment in only selected patients.

Evaluation of in-stent restenosis in proximal coronary arteries with multidetector computed tomography (MDCT)

The purpose of this study was to assess the ability of 16-slice computed tomography (CT) to detect in-stent restenosis of proximal coronary arteries. From November 2002 to April 2004, 134 consecutive patients with proximal stents (3.25 +/- 0.47 mm) were prospectively studied. Multidetector CT (MDCT) was performed 24 h (baseline) and 6 months after angioplasty and analysed by two radiologists blinded to the results of the coronary angiography. Sensitivity, specificity, positive and negative predictive values for in-stent restenosis were compared with conventional quantitative coronary angiography (QCA). Stenosis with a diameter >or=50% was considered diagnostic of in-stent restenosis. The CT analysis was performed in 131 and 114 patients at baseline and 6 months, respectively. The in-stent lumen was evaluable in 111 (121 stents) and 99 patients (108 stents) at baseline and 6 months, respectively. The prevalence of in-stent restenosis was 22.5%. Restenoses were correctly identified in 91.7 and 87.5% by the two radiologists. The sensitivity, specificity, positive and negative predictive values for the assessment of significant in-stent restenosis were 92, 67, 43, 97% and 87, 66, 41, 95% for the radiologists, respectively. MDCT is a potential non-invasive technique for the screening of in-stent restenosis of proximal coronary arteries that needs further improvements.

Recently Patented Applications of Homologous Cellular and Extracellular Agents as Therapeutics or Targets for the Prevention of Restenosis Post- Angioplasty

Currently available drug-eluting stents have been shown to reduce the prevalence of in-stent restenosis. However, their use is limited by their enormous cost and unwanted side effects associated with both drugs, sirolimus and paclitaxel, presently used to coat most of the stents clinically available. Due to their lack of selectivity with respect to targeted cell types these drugs do not only inhibit vascular smooth muscle cell proliferation underlying neointima formation, they also compromise endothelial repair increasing the risk for subacute thrombosis following implantation of drug-eluting stents. Accordingly, there is need for new cost-effective agents capable to inhibit restenosis without clinically relevant, unwanted side effects. In the present paper a selection of the most important patent applications published within the last 3 years and claiming the use of homologous cellular and extracellular agents as therapeutics or targets to prevent restenosis are reviewed. Such agents include c-Jun, the focal adhesion kinase (FAK) and its inhibitor FAK-related non-kinase (FRNK), estrogen receptors, variants of vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2) as well as some so far poorly characterized factors supposedly involved in the control of cell proliferation, inflammation and apoptosis. Such agents promise to be cost-effective and, in some cases, potentially devoid of unwanted side effects. Clinical long-term studies have yet to support such notions.