In-stent Restenosis Research Articles

Monocyte to high-density lipoprotein cholesterol ratio predicts restenosis of drug-eluting stents in patients with unstable angina pectoris

Several studies have shown that the monocyte count to high-density lipoprotein cholesterol ratio (MHR) serves as a predictive marker for in-stent restenosis (ISR) of bare-metal stents (BMSs). However, the ability of the MHR to predict ISR in patients with drug-eluting stents (DESs) remains uncertain. This study aimed to investigate the predictive value of the MHR for ISR in patients with unstable angina pectoris who have undergone primary DES implantation. A total of 474 consecutive patients with unstable angina pectoris who underwent successful DES-based percutaneous coronary intervention (PCI) from 01-12-2014 to 01-12-2022 were enrolled in the study. Patients were divided into the ISR group and the non-ISR group on the basis of the follow-up results of coronary angiography. The demographic and clinical characteristics of the patients were documented. The MHR was calculated via the following formula: . Multivariate logistic regression models were developed to evaluate the predictive value of the MHR for DES-ISR. The baseline MHR was notably greater in the ISR group than in the non-ISR group (P < 0.001). After adjusting for confounding factors, the MHR emerged as an independent predictor of ISR (OR = 1.244; 95%CI 1.171–1.321). Receiver operating characteristic (ROC) curve analysis revealed that MHR for predicting ISR had an AUC of 0.752 (95% CI 0.708–0.796). For a MHR > 7.32, the sensitivity was estimated to be 59.8% (95% CI 47.2-66.5%) and the specificity was 81.2% (95% CI 71.2-86.4%). Including the MHR in the predictive model for ISR improved the area under the curve (0.698 vs. 0.782, P < 0.001), categorical net reclassification improvement (0.703; 95%CI 0.536–0.871), and integrated discrimination improvement (0.121; 95%CI 0.092–0.151). The MHR can be used to predict DES-ISR in patients with unstable angina pectoris, indicating that the MHR may serve as a valuable marker for risk stratification and prognosis in individuals undergoing DES implantation.

Optical coherence tomography versus angiography to guide percutaneous coronary intervention in patients with in-stent restenosis: an observational study.

Although optical coherence tomography (OCT) guidance with the 'MLDMAX' criteria is very useful for de-novo lesions during percutaneous coronary intervention (PCI), there are limited studies on its benefits in patients with in-stent restenosis (ISR). This study aimed to compare the clinical outcomes of patients with ISR who underwent repeat PCI (re-PCI) with OCT or angiographic guidance. This retrospective study enrolled 2142 patients with ISR who underwent re-PCI at Nanjing First Hospital from January 2016 to January 2023. The primary endpoint was the incidence of target vessel failure (TVF) post-re-PCI within 3 years. The secondary endpoints included each component of TVF. After propensity score matching, 161 matched pairs were enrolled. OCT guidance of re-PCI was associated with a significantly lower risk of TVF compared with angiographic guidance alone [hazard ratio (HR), 0.51; 95% confidence interval (CI), 0.31-0.83; P = 0.007] in patients with ISR. However, only 68.9% of patients with ISR met the final criteria of 'MLDMAX' post-re-PCI, which was associated with a lower risk of TVF compared with patients without meeting the OCT criteria (HR, 0.24; 95% CI, 0.11-0.54; P < 0.001), and satisfied the angiographic criteria (HR, 0.40; 95% CI, 0.19-0.85; P = 0.017). Compared with angiographic guidance, OCT guidance significantly reduced TVF risk following re-PCI for ISR lesions, especially for patients who met the final criteria of 'MLDMAX'.

Higher serum cystatin C and matrix metalloproteinase 9 levels effectively predict in-stent restenosis after stent implantation for intracranial and extracranial arterial stenosis

ObjectiveThis paper was performed to unravel the predictive value of serum cystatin C (Cys C) and matrix metalloproteinase 9 (MMP-9) levels before vascular stent implantation for in-stent restenosis (ISR) 6-12 months after stent implantation for intracranial and extracranial arterial stenosis. MethodsOne hundred and ninety-eight patients who underwent dilatation stenting for intracranial and extracranial arterial stenosis and completed Digital Subtraction Angiography or head and neck CT- Angiography review were selected for the study and were divided into ISR group (n = 33) and no ISR (NISR) group (n = 165) according to the presence or absence of ISR. Serum levels of Cys C, MMP-9, triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), uric acid (UA), creatinine (Cr), homocysteine (Hcy), fibrinogen (FIB), total bilirubin (TBIL), endothelin-1 (ET-1), nitric oxide (NO), angiotensin II (Ang II), interleukin-6 (IL-6), tumor necrosis factor (TNF-α), and C-reactive protein (CRP) levels before vascular stent implantation were examined and compared between groups. ROC curves were employed for analyzing the predictive value of serum Cys C and MMP-9 alone or in combination for ISR. Pearson test was utilized for analyzing the serum Cys C and MMP-9 with vasoactive substances and inflammatory cytokines in patients in the ISR group. Logistic regression analysis was implemented to analyze the factors influencing ISR 6-12 months after stent implantation for intracranial and extracranial arterial stenosis. ResultsCys C, MMP-9, LDL, UA, Cr, Hcy, FIB, ET-1, NO, Ang II, IL-6, TNF-α, and CRP were higher in the ISR group than in the NISR group, and TBIL was lower than in the NISR group (P < 0.05). The AUC of the combined serum Cys C and MMP-9 (AUC = 0.900) was greater than that of Cys C (AUC = 0.685) or MMP-9 (AUC = 0.870) alone (P < 0.05). Cys C and MMP-9 levels were positively correlated with ET-1, NO, Ang II, IL-6, TNF-α, and CRP (r > 0, P < 0.05). Increased levels of Cys C, MMP-9, LDL-C, UA, Cr, Hcy, FIB, ET-1, NO, Ang II, IL-6, TNF-α, and CRP, and diabetes were risk factors for the development of ISR (OR > 1, P < 0.05), and TBil was protective factor (OR < 1, P < 0.05). ConclusionSerum Cys C combined with MMP-9 levels are effective in predicting ISR.

Data-driven reduced order surrogate modeling for coronary in-stent restenosis

Background:The intricate process of coronary in-stent restenosis (ISR) involves the interplay between different mediators, including platelet-derived growth factor, transforming growth factor-β, extracellular matrix, smooth muscle cells, endothelial cells, and drug elution from the stent. Modeling such complex multiphysics phenomena demands extensive computational resources and time. Methods:This paper proposes a novel non-intrusive data-driven reduced order modeling approach for the underlying multiphysics time-dependent parametrized problem. In the offline phase, a 3D convolutional autoencoder, comprising an encoder and decoder, is trained to achieve dimensionality reduction. The encoder condenses the full-order solution into a lower-dimensional latent space, while the decoder facilitates the reconstruction of the full solution from the latent space. To deal with the 5D input datasets (3D geometry + time series + multiple output channels), two ingredients are explored. The first approach incorporates time as an additional parameter and applies 3D convolution on individual time steps, encoding a distinct latent variable for each parameter instance within each time step. The second approach reshapes the 3D geometry into a 2D plane along a less interactive axis and stacks all time steps in the third direction for each parameter instance. This rearrangement generates a larger and complete dataset for one parameter instance, resulting in a singular latent variable across the entire discrete time-series. In both approaches, the multiple outputs are considered automatically in the convolutions. Moreover, Gaussian process regression is applied to establish correlations between the latent variable and the input parameter. Results:The constitutive model reveals a significant acceleration in neointimal growth between 30−60 days post percutaneous coronary intervention (PCI). The surrogate models applying both approaches exhibit high accuracy in pointwise error, with the first approach showcasing smaller errors across the entire evaluation period for all outputs. The parameter study on drug dosage against ISR rates provides noteworthy insights of neointimal growth, where the nonlinear dependence of ISR rates on the peak drug flux exhibits intriguing periodic patterns. Applying the trained model, the rate of ISR is effectively evaluated, and the optimal parameter range for drug dosage is identified. Conclusion:The demonstrated non-intrusive reduced order surrogate model proves to be a powerful tool for predicting ISR outcomes. Moreover, the proposed method lays the foundation for real-time simulations and optimization of PCI parameters.

Randomized Controlled Trial of Cilostazol Addition for In-Stent Restenosis After Carotid Artery Stenting.

Restenosis after carotid artery stenting (CAS) is associated with the risk of developing ischemic stroke. We aimed to evaluate the inhibitory effect of cilostazol addition on in-stent restenosis (ISR) in patients treated with CAS. In a randomized, open-label, blind-end point trial, patients with symptomatic and asymptomatic carotid artery stenosis and scheduled for CAS were randomly assigned to adding cilostazol (50 or 100 mg, twice per day) on other antiplatelets from 3 days before CAS or not adding cilostazol. Concomitant use of other antiplatelets was unrestricted. ISR was diagnosed by a peak systolic velocity of at least 1.75 m/s on duplex ultrasonography. The primary outcome was incidence of ISR within 2 years after CAS. Secondary outcomes included occurrences of cardiovascular events or any death and hemorrhagic events. Participants were recruited from December 2010 to September 2015. Although the sample size was initially set to be 900 (450 in each group), 631 patients (mean age 69.9 years, 558 men, 325 in the cilostazol, and 306 in the noncilostazol group) were included in the primary analysis. Within 2 years' follow-up, ISR occurred in 31 of 325 patients (cumulative incidence 10.8%) in the cilostazol group and 46 of 306 patients (19.6%) in the noncilostazol group (hazard ratio, 0.64 [95% CI, 0.41-1.0]; P=0.056). In the exploratory analysis, incidence of ISR beyond 30 days after CAS was lower in the cilostazol group than in the noncilostazol group (10.3% versus 19.3%; P=0.040). Incidences of cardiovascular events or any death and hemorrhagic events were similar between the groups (6.2% versus 6.7% and 2.3% versus 1.4%, respectively). The addition of cilostazol to other antiplatelet agents could contribute to the reduction of ISR in the chronic stage of patients who underwent CAS, the authenticity of which depends on further studies with sufficient statistical power. URL: https://www.clinicaltrials.gov; Unique identifier: NCT01261234.

Non-target lesion progression: Unveiling critical predictors and outcomes in patients with in-stent restenosis

BackgroundPercutaneous coronary intervention (PCI) has become the primary treatment for coronary artery disease. However, while PCI effectively addresses severe stenosis or occlusive lesions in target vessels, the progression of non-target vessel plaque remains a critical determinant of long-term patient prognosis. AimsThe purpose of this study was to investigate the impact of non-target vascular plaque progression on prognosis after PCI for ISR. MethodsThis study included 195 patients diagnosed with ISR and multivessel disease who underwent successful PCI with drug-eluting stent (DES) placement, along with intraoperative optical coherence tomography (OCT) assessment of the culprit stent. Subsequent rechecked coronary angiography categorized eligible patients into non-target lesion progression (N-TLP) and no-N-TLP groups. We evaluated the baseline morphological characteristics of N-TLP by OCT and investigated the relationship between N-TLP, non-culprit vessel-related major adverse cardiovascular events (NCV-MACE), and pan-vascular disease-related clinical events (PVD-CE) incidence. ResultsMultivariate logistic regression analysis revealed that diabetes mellitus (OR 3.616, 95% CI: 1.735–7.537; P = 0.001), uric acid level (OR 1.005, 95% CI: 1.001–1.009; P = 0.006), in-stent neoatherosclerosis (ISNA) (OR 1.334, 95% CI: 1.114–1.985; P = 0.047) and heterogeneous neointima morphology (OR 2.48, 95% CI: 1.18–5.43; P = 0.019) were independent predictors for N-TLP. Furthermore, N-TLP was associated with a high incidence of NCV-MACE (19.4% vs 6.9%, P = 0.009) and PVD-CE (83.9% [95% CI: 79.7%–88.3%] vs 93.1% [95% CI: 88.4%–98.0%], P = 0.038) after PCI in ISR patients. ConclusionDiabetes, uric acid levels, ISNA, and heterogeneous neointima are predictive factors for subsequent rapid plaque progression, with N-TLP exacerbating the incidence of NCV-MACE and PVD-CE after PCI.

First-in-man study of a novel everolimus-coated balloon for the treatment of coronary in-stent restenosis.

Treatment of patients with in-stent restenosis (ISR) remains challenging. In this setting the use of drug-coated balloons (DCB) represents an attractive approach to avoid adding another metal layer to the coronary wall. The Chansu Vascular Technologies (CVT)-ISR trial aimed to evaluate the safety and efficacy of a novel everolimus-DCB (CVT-DCB) using a new coating formulation and crystalline everolimus. The CVT-ISR trial was a prospective, multicenter, open, single-arm, first-in-man (FIM) study. A total of 51 patients (mean age 69.2 years, 74.5% male) with single ISR coronary lesions (≤24 mm in length) were enrolled at nine sites in Europe. The primary safety endpoint, freedom from target lesion failure (TLF) at 180 days, was 92.2%, with the lower bound of the 95% confidence interval (81.1%), above the protocol-defined objective performance criterion (OPC) (65% for conventional balloon angioplasty, P < 0.05). At 1 year freedom from TLF was 90.2%. The primary efficacy endpoint, in-stent late lumen loss at 180 days (evaluated in a predefined subgroup of 25 patients scheduled for late angiography), was 0.40 mm (median 0.30 mm), lower than the protocol-defined OPC of the plain balloon angioplasty historical control (0.80 mm, P < 0.001). This FIM study demonstrated the superior efficacy of the new everolimus CVT-DCB compared with conventional balloon angioplasty in the treatment of patients with ISR. NCT05731700.

A Case Report of Late Vessel Occlusion Presenting as ST-Segment Elevation Myocardial Infarction After Drug-Coating Balloon Treatment of In-Stent Restenosis

Abstract Background Drug-coated balloons (DCB) offer an appealing therapeutic alternative for the treatment of patients with coronary in-stent restenosis (ISR). In-segment late lumen loss, translating into recurrent ISR and the clinical need for target lesion revascularization represent a well-established and thoroughly investigated limitation of DCB in this setting. However, abrupt vessel occlusion, clinically presenting as ST-segment elevation myocardial infarction (STEMI), has not been previously described after DCB therapy for ISR. Case summary We herein present the case of a 70-year-old patient that underwent percutaneous coronary intervention (PCI) with DCB for ISR. Despite achieving an excellent acute angiographic result (with no flow-limiting dissection and minimal angiographic residual stenosis), the patient presented 3 months later with STEMI due to occlusion of the previously treated segment. After adequate lesion preparation, a drug-eluting stent was implanted with optimal final angiographic result. The patient was discharged 2 days after the PCI without any post-procedural complications and remained asymptomatic at 6-month clinical follow-up. Discussion This case report is the first description of an abrupt vessel occlusion presenting as STEMI following a DCB angioplasty for ISR. This exceptional presentation does not dismount the solid evidence supporting the long-term safety of DCB in these challenging patients.

Drug-Coated Balloons Versus Drug-Eluting Stents or Plain Old Balloon Angioplasty: A Long-Term in-Stent Restenosis Study.

Balloon angioplasty with drug-coated balloons (DCBs) is frequently used during percutaneous coronary intervention for in-stent restenosis. Despite its frequent use, there is a lack of long-term data on the efficacy of DCB angioplasty. We conducted an investigation on the long-term efficacy outcome of in-stent restenosis, comparing DCBs, drug-eluting stents, and plain old balloon angioplasty. We conducted a nationwide analysis from the SCAAR (Swedish Coronary Angiography and Angioplasty Registry) including in-stent restenosis lesions undergoing coronary angiography between June 11, 2013, and January 14, 2022. The primary outcome of this study was target-lesion revascularization within a 5-year follow-up. Secondary outcomes included all-cause death, cardiovascular death, myocardial infarction, and any percutaneous coronary intervention. The outcomes were analyzed using a multivariable Cox proportional hazard model or Poisson regression, as appropriate. A total of 10 561 lesions from 9062 patients were included. Compared with plain old balloon angioplasty, the use of DCB angioplasty was associated with less target-lesion revascularization (risk ratio, 0.69 [95% CI, 0.57-0.82]), all-cause death (risk ratio, 0.72 [95% CI, 0.59-0.88]), and cardiovascular death (hazard ratio [HR], 0.59 [95% CI, 0.45-0.78]). No difference was observed for myocardial infarction or any percutaneous coronary intervention. Compared with drug-eluting stents, the use of DCBs was associated with higher rates of target-lesion revascularization (HR, 1.20 [95% CI, 1.06-1.37]). No difference was observed for all-cause death, cardiovascular death, myocardial infarction, or any percutaneous coronary intervention. In this long-term nationwide analysis, the use of DCB angioplasty showed superior outcomes compared with plain old balloon angioplasty within 5 years but higher rates of repeat revascularizations compared with drug-eluting stents.

RapidBrachyIVBT: A dosimetry software for patient-specific intravascular brachytherapy dose calculations on optical coherence tomography images.

Coronary artery disease is the most common form of cardiovascular disease. It is caused by excess plaque along the arterial wall, blocking blood flow to the heart (stenosis). A percutaneous coronary intervention widens the arterial wall with the inflation of a balloon inside the lesion area and leaves behind a metal stent to prevent re-narrowing of the artery (restenosis). However, in-stent restenosis may occur due to damage to the arterial wall tissue, triggering neointimal hyperplasia, producing fibrotic and calcified plaques and narrowing the artery again. Drug-eluting stents, which slowly release medication to inhibit neointimal hyperplasia, are used to prevent in-stent restenosis but fail up to 20% of cases. Coronary intravascular brachytherapy (IVBT), which uses -emitting radionuclides to prevent in-stent restenosis, is used in these failed cases to prevent in-stent restenosis. However, current clinical dosimetry for IVBT is water-based, and heterogeneities such as the guidewire of the IVBT device, fibrotic and calcified plaques and stents are not considered. This study aimed to develop a Monte Carlo-based dose calculation software, accounting for patient-specific geometry from Optical Coherence Tomography (OCT)images. RapidBrachyIVBT, a Monte Carlo dose calculation software based on the Geant4 toolkit v. 10.02.p02, was developed and integrated into RapidBrachyMCTPS, a treatment planning system for brachytherapy applications. The only commercially available IVBT delivery system, the Novoste Beta-Cath 3.5F, with a source train, was modeled with 30, 40, and 60mm source train lengths. The software was validated with published TG-149 parameters compared to Monte Carlo simulations in water. The dose calculation engine was tested with OCT images from a patient undergoing coronary IVBT for recurrent in-stent restenosis at Brigham and Women's Hospital in Boston, Massachusetts. Considering the heterogeneities, the images were segmented and used to calculate the absorbed dose to water and the absorbed dose to medium. The prescribed dose was normalized to 23Gy at 2.0mm from the source center, which is the target volume in IVBT. The dose rate values in water obtained using RapidBrachyIVBT aligned with TG-149 consensus values, showing agreement within a range of 0.03% to 1.7%. Considering the heterogeneities present in the patient's OCT images, the absorbed dose in the entire artery segment was up to 77.5% lower, while within the target volume, it was up to 56.6% lower, compared to the dose calculated in a homogeneous waterphantom. RapidBrachyIVBT, a Monte Carlo dose calculation software for IVBT, was developed and successfully integrated into RapidBrachyMCTPS, a treatment planning system for brachytherapy applications, where accurate attenuation of the absorbed dose by heterogeneities isconsidered.

Factors associated with recurrence after drug-coated balloon therapy for femoropopliteal in-stent restenosis

Factors associated with recurrence after drug-coated balloon therapy for femoropopliteal in-stent restenosis

In-silico Analysis of In-stent Restenosis Prediction of Stented Renal Artery

In-stent restenosis (ISR) is a common complication after renal artery stenting, and stent design may influence the formation of ISR. This study aims to predict the effect of stent design on the risk of ISR formation after renal artery stenting. Using computer-aided design, a simplified renal artery model was modelled and later assembled with stents similar to commercial stents. Computational Fluid Mechanics (CFD) analysis was employed to simulate the blood flow in these stented models. Stent 1 exhibited superior hemodynamic performance with minimal low Wall Shear Stress (WSS) exposure in the stented region. Additionally, the study found that the thinnest Stent 1 was the most effective in reducing the risk of ISR formation. Thus, stent strut configuration with largespacing may reduce ISR risk, with the thinnest Stent 1 design showed promising performance in mitigating ISR. Hence, it is worth further investigation.

Interwoven nitinol stent-assisted arteriovenous fistula maturation: 2 year-outcomes of a single center experience.

The aim of this study was to report 2-year outcomes of interwoven nitinol (SuperaTM) stent-assisted arteriovenous fistula (AVF) maturation in patients who presented with non-matured AVF. We reviewed the clinical data of 20 patients who presented with non-matured AVF (19 patients with brachiocephalic AVF and 1 patient with radiocephalic AVF) and underwent balloon angioplasty followed by SuperaTM stenting in the cephalic vein for long-term hemodialysis between January 2017 and January 2022. The outcomes were evaluated in these patients in terms of technical success, post-intervention complications, reintervention, and cumulative patency (6months, 1year, and 2years). The study included 20 patients who presented with non-matured AVF. The mean age of the patients was 65 years (range, 40-85). The SuperaTM stents of size 6.5mm were used in 15 patients (75%), and those of 7.5mm and 5.5mm were used in 4 (20%) and 1 (5%) patient, respectively. The average stent length was 99.5mm (range, 80-120). Technical success was achieved in all patients. Early use within 1 week by needling at the SuperaTM stent segment (cannulation zone) was successful in all patients without any complications. The mean follow-up time was 24.5 months. During the follow-up period, reinterventions to maintain the function of AVF were performed in 8 patients (40%) (7 patients with juxta-anastomotic stenosis, 1 patient with in-stent restenosis). The reintervention rate was 0.39 procedures per patient per year. The primary patency at 6 months, 1 year, and 2 years were 85.5%, 62.6%, and 54.2%, respectively. The assisted primary patency at 6 months, 1 year, and 2 years were 95%, 84.5%, and 78.8%, respectively. The use of the SuperaTM stent to improve the AVF maturation rate was associated with acceptable outcomes at 2 years. Its benefit over other strategies was the early use of the access for hemodialysis.

Abstract 4136442: Efficacy and Safety of Paclitaxel-coated balloons versus Uncoated balloons in the Management of Coronary in-stent restenosis: a Meta Analysis of Randomized Controlled Trials

Introduction: Coronary in-stent restenosis (ISR) remains challenging despite stent technology advancements. Paclitaxel-coated balloons (PCB) offer a promising non-implant approach to deliver antiproliferative agents directly to the vessel wall. This meta-analysis aims to evaluate the comparative effectiveness of PCB versus uncoated balloons (UCB) in managing coronary ISR to address emerging safety concerns. Methodology: Medline, Scopus and Embase were searched until April 2024 for randomized controlled trials (RCTs) comparing PCB versus UCB in patients undergoing coronary ISR. Primary outcomes were in-segment late lumen loss (LLL), binary restenosis, target lesion revascularization (TLR), major adverse cardiac events (MACE), and mortality. Secondary outcomes included in-stent LLL, in-stent binary restenosis, myocardial infarction (MI), cardiac death, target vessel MI, and target vessel revascularization (TVR). Results: This meta-analysis includes seven RCTs with 1,408 patients (PCB = 864, UCB = 544). PCB significantly reduced in-segment LLL (MD= -0.50, 95% CI [-0.67, -0.33]; P &lt; 0.00001), in-segment binary restenosis (RR= 0.25, 95% CI [0.14, 0.45]; P &lt; 0.00001), target lesion revascularization (RR= 0.43, 95% CI [0.32, 0.58]; P &lt; 0.00001), mortality (RR=0.56, 95% CI [0.39, 0.80]; P=0.001), and MACE (RR= 0.36, 95% CI [0.25, 0.51]; P &lt; 0.00001). PCB also significantly decreased in-stent LLL (MD= -0.52, 95% CI [-0.72, -0.32]; P &lt; 0.00001), in-stent binary restenosis (RR = 0.19, 95% CI [0.11, 0.35]; P &lt; 0.00001), and TVR (RR = 0.45, 95% CI [0.29, 0.70]; P = 0.0003). PCB showed a short-term reduction in MACE and target lesion revascularization at 6 months, 1 year and 3 years of followup. No difference was observed in MI, cardiac death, or target vessel MI. Conclusion: In patients with coronary ISR, PCB are associated with reduced in-segment LLL, in-segment binary restenosis events, target lesion revascularization, mortality, MACE, in-stent LLL, in-stent binary restenosis and target vessel revascularization.

Abstract 4142793: Development of an Angiography-Based Multimodal AI Model for Predicting the risk of In-Stent Restenosis

Background: Despite advances in Second-generation drug-eluting stents (DES), 5-10% of patients still experience in-stent restenosis (ISR) after percutaneous coronary intervention (PCI), which generates significant financial burden and elevates the risk of acute coronary syndrome (ACS) and rehospitalization. Thus, early identification of patients at high risk for ISR is crucial for guiding clinical stratification and early intervention. Aims: To develop and validate a multimodal artificial intelligence (AI) model based on coronary angiography images for predicting ISR risk in patients post-DES implantation. Methods: To establish an accurate predictive model, our approach begins with the pre-training on 100,000 angiographic images to enhance the model’s capability in recognizing image features. Subsequently, we employ the DenseNet architecture as the primary deep learning model, incorporating angiographic images from 2,000 cases of DES-treated de novo lesions—1,000 from patients who did not experience ISR within two years and 1,000 from those who did. A multivariate logistic regression analysis, including radiomic features, clinical baselines, and functional information, constructs the predictive model. Additionally, a separate prospective cohort of 300 cases was assembled for validation to simulate real-world application and to verify the model's reliability and accuracy. Results: Our study successfully developed an AI prediction model for ISR, utilizing a large cohort of coronary angiography images, which effectively predicts ISR with high accuracy. Leveraging the DenseNet architecture and finely tuned machine learning algorithms, the model achieved a sensitivity and specificity of 90% in the validation cohort. The ROC curve from the test phase demonstrated an AUC above 0.90, underscoring the model’s exceptional diagnostic capabilities. Furthermore, the implementation of this model in a prospective cohort confirmed its reliability and practical utility in real-world clinical settings. Conclusions: This study introduces the first multimodal AI model using angiographic imaging to predict ISR. By demonstrating high diagnostic accuracy and reliability in real-world settings, this model serves as an essential tool for early ISR detection and intervention, ultimately helping to reduce the incidence of major adverse cardiac events (MACEs) and mortality.

Abstract 4125106: Paclitaxel-Coated Balloon vs Uncoated Balloon for Coronary In-Stent Restenosis; A Meta-Analysis.

Background: Internationally, drug-coated balloons have emerged as a new treatment approach in In-Stent Restenosis (ISR) offering localized drug delivery to inhibit neointimal growth without the need for additional stent layers. However, their use has not been assessed or approved in the United States. Paclitaxel-coated balloons (PCBs) are gaining traction as alternatives for in-stent restenosis patients. Yet, their safety and effectiveness compared to uncoated balloons remain uncertain. This meta-analysis seeks to systematically assess PCBs' safety and efficacy for ISR treatment by comparing them to uncoated balloons. Research Question: Are paclitaxel-coated balloons (PCBs) superior to uncoated balloons (UCBs) in terms of safety and efficacy for the treatment of coronary in-stent restenosis (ISR)? Aims: Systematically assess the safety and efficacy of paclitaxel-coated balloons (PCBs) compared to uncoated balloons (UCBs) for the treatment of coronary in-stent restenosis (ISR). Methods: A comprehensive literature review was conducted utilizing multiple databases up to May 2024, focusing on randomized controlled trials comparing PCB vs UCB in patients with coronary in-stent restenosis. Six randomized controlled trials with a total of 1,347 patients who completed 1-year follow-up were included. Dichotomous data were calculated as odds ratios (ORs) and 95% confidence intervals (95% CI). P&lt;0.05 was considered to indicate a statistically significant difference. The primary outcomes included Target Lesion Revascularization (TLR), Myocardial Infarction (MI), Stent Thrombosis (ST) and Total Mortality (TM). Results: Compared with patients who underwent UCB angioplasty, those in the PCB group exhibited a clear superiority in TLR [odds ratio (OR), 0.21; 95% CI [ 0.11,0.41]; P&lt;0.00001], and MI [odds ratio (OR), 0.55; 95% CI [0.33,0.91]; P&lt;0.02]. ST was numerically lower in the PCB arm without statistical significance (OR, 0.21; 95% CI [0.03,1.48]; P=0.11). TM was also numerically lower with PCB without reaching statistical significance (OR, 0.60; 95% CI [0.32,1.11]; P=0.10). Conclusion: This meta analysis supports that PCBs are associated with superior outcomes when compared with UCBs in the management of ISR. Paclitaxel-coated balloons are an effective treatment option for patients with coronary in-stent restenosis as demonstrated by superior outcomes in target lesion revascularization and recurrent myocardial infarction.

Abstract 4120966: Outcomes Following Balloon Angioplasty with Drug Coated Versus Uncoated Balloons in Patients with Coronary In-Stent Restenosis: A Systematic Review and Meta-Analysis

Background &lt;div&gt; &lt;/div&gt; &lt;div&gt;The development of in-stent restenosis (ISR) has emerged as a substantial barrier to interventional treatment for coronary heart disease. Drug-coated balloon (DCB) is an efficacious interventional technique for the management of ISR. This meta-analysis compares the efficacy of DCB in the treatment of ISR with that of an uncoated balloon (UCB).&lt;/div&gt; &lt;div&gt; &lt;/div&gt; &lt;div&gt;Methods&lt;/div&gt; &lt;div&gt; &lt;/div&gt; &lt;div&gt;We comprehensively searched literature on MEDLINE, Embase, Cochrane, and clinicaltrials.gov using MeSH terms and relevant keywords for “Balloon Angioplasty” and “in-stent Restenosis” from inception to June 1, 2024, followed by a meta-analysis of all randomized controlled trials (RCTs) to assess both strategies for treatment of ISR. Random effects model was used to aggregate the risk ratios (RR) for dichotomous and mean differences (MD) for continuous outcomes, with 95% confidence intervals (CI).&lt;/div&gt; &lt;div&gt; &lt;/div&gt; &lt;div&gt;Results&lt;/div&gt; &lt;div&gt; &lt;/div&gt; &lt;div&gt;The search strategy retrieved 2330 studies. Duplicates and irrelevant articles were removed and data from seven RCTs (1,408 patients) was extracted. The mean age ranged from 64 to 74 years. The mean clinical follow-up ranged from 1 to 10 years. DCB was found to be superior to UCB at latest follow up in terms of target lesion revascularization (TLR) (RR 0.34, 95% CI 0.19-0.58; p 0.0001; I2 79%), major adverse cardiovascular events (MACE) (RR 0.41, 95% CI 0.23-0.73; p 0.003; I2 84%), late lumen loss (LLL) (MD -0.46 mm, 95% CI -0.64- -0.28]; p &lt;0.00001; I2 64%), and target vessel revascularization (TVR) (RR 0.45, 95% CI 0.29-0.70; p 0.0003; I2 67%). The two groups were comparable at latest follow up in terms of mortality (RR 0.87, 95% CI 0.65-1.16; p 0.35; I2 0%), cardiac death (RR 0.89, 95% CI 0.66-1.19; p 0.43; I2 0%), myocardial infarction (MI) (RR 0.70, 95% CI 0.39-1.24; p 0.22; I2 28%) and stent thrombosis (RR 0.22, 95% CI 0.04-1.10; p 0.06; I2 46%).&lt;/div&gt; &lt;div&gt; &lt;/div&gt; &lt;div&gt; &lt;/div&gt; &lt;div&gt; &lt;/div&gt; &lt;div&gt;Conclusion&lt;/div&gt; &lt;div&gt; &lt;/div&gt; &lt;div&gt;DCB showed promising results in the treatment of patients with coronary ISR. DCB outperformed UCB in significantly reducing TLR, MACE, LLL and TVR risks. The risk of mortality, cardiac death, MI, and stent thrombosis was similar between DCB and UCB.&lt;/div&gt; &lt;div&gt; &lt;/div&gt; &lt;div&gt; &lt;/div&gt;

Abstract 4145821: Serial Vascular Responses of Balloon-expandable Stent with Biodegradable Film-type Graft in a Rabbit Iliac Artery Dissection Model (BioGard Study)

Introduction and Background: Arterial dissection during endovascular therapy rarely occurs but can be lethal. A significant blood volume extravasation during coronary artery interventions is related to the very high mortality (20-30%). In this hyperacute emergent clinical situation, covered stents have been considered as a primary measure to prevent further serious arterial events. A fabric-based covered graft stents yield poor clinical outcomes. To overcome these challenges, the balloon-expandable stent with biodegradable film-type graft for treating arterial dissection was invented. Research Questions and Objectives: A novel balloon-expandable stent with biodegradable film graft for overcoming these issues would be valid for efficacy and safety in a rabbit iliac artery dissection model. Method and Approach: Eighteen iliac artery dissections were induced by balloon over-inflation on angiography (Ellis type 2 or 3) and treated using the test device (3.0 x 24 mm). Subsequently, twelve animals underwent histologic examinations and micro-computed tomography (CT) at 0, 2, 4, and 8 weeks and 3, 6, 9, and 12 months and angiography at one-year. Results and Data: There were no adverse cardiovascular events during the one-year. Early-stage histologic examination revealed complete sealing of disrupted vessels by the device, exhibiting mural hematoma, peri-stent red thrombi, and dense infiltration of inflammatory cells. Mid- and long-term histologic examination showed patent stents with neointimal hyperplasia over the stents (% area stenosis: 11.8 at 2weeks, 26.1 at 1month, 29.7 at 3months, 49.2 at 9months, and 51.0 at 1year), along with mild peri-strut inflammatory response (Grade: 1-2 at mid-term and 0-1 at long-term). The graft film became scarcely visible after six months. Both CT and angiography revealed no instances of thrombotic occlusion or in-stent restenosis (% diameter stenosis: 5.7 at 2weeks, 12.3 at 1month, 14.2 at 3months, 25.1 at 9months, and 26.6 at 1 year). Conclusion: The novel balloon-expandable stent with a biodegradable film graft demonstrates feasibility in managing severe artery dissection and preventing lethal vascular events in animal model. Future human studies are warranted to validate these findings and elucidate the clinical outcomes of the study.

Abstract 4137019: Paclitaxel-Coated Balloon vs Uncoated Balloon for Coronary In-Stent Restenosis: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Background: Despite the effectiveness of drug-eluting stents (DES) in preventing restenosis, many patients still experience DES restenosis. Neointimal hyperplasia and neoatherosclerosis can develop within these stents, leading to recurrent coronary syndromes. Hypothesis: Repeated stenting with DES is limited by additional metal layers, the need for prolonged dual antiplatelet therapy, and heightened risks of stent thrombosis. Locally acting drugs with sustained efficacy may prevent this progression. Paclitaxel delivery via contrast medium or drug-coated balloon catheters could exert antiproliferative effects, reducing neointimal proliferation. Aims: To synthesize existing evidence on the efficacy and safety of Paclitaxel-Coated Balloons versus Uncoated Balloons in coronary in-stent restenosis. Methods: Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we searched five electronic databases (PubMed, EMBASE, Cochrane Library, Scopus, and Web of Science) to identify eligible studies reported up to March 23, 2024. Using R version 4.4.0, we reported outcomes as risk ratios (RRs) or mean differences (MD) and confidence intervals (CIs). This review has been registered and published in PROSPERO (CRD42024527412). Results: The meta-analysis included a total of six trials with 1,541 patients. PCB significantly reduced the incidence of myocardial infarction (RR 0.65, 95% CI [0.42, 1.00], p = 0.052), stent thrombosis (RR 0.26, 95% CI 0.08, to 0.83], p = 0.023), major adverse cardiac events (RR 0.32, 95% CI 0.25, to 0.42], P &lt; 0.001), target lesion revascularization (RR 0.34, 95% CI [0.14, 0.84], p &lt; 0.001). No significant differences were observed between PCB and UCB regarding cardiac-related mortality, target vessel revascularization, percutaneous coronary intervention, all-cause death, Q wave and non-Q wave myocardial infarction, coronary artery bypass grafting, and target vessel failure. Conclusion: PCB for ISR significantly reduced the incidence of myocardial infarction, MACE, and stent thrombosis compared to UCB.

Abstract 4138792: A Case of Right Coronary Artery Chronic Total Occlusion in a Transplanted Heart: To Stent or Not to Stent?

Background: Cardiac Allograft Vasculopathy (CAV) is commonly seen in transplanted hearts. Due to the absence of innervation, many transplanted patients have no symptoms despite extensive disease. This poses a challenge in deciding when to perform coronary interventions. We present a case of significant CAV on surveillance angiogram that posed a challenge in management. Case: A 67-year-old female presented for her fifth surveillance coronary angiography nine and a half years after her heart transplant. The angiogram revealed ostial right coronary artery (RCA) chronic total occlusion (CTO) with left-to-right collaterals as well as diffuse irregularities in the left anterior descending (LAD) and left circumflex arteries. The patient was asymptomatic and two years prior to that, her angiogram revealed no significant disease. Biopsies for the past nine years showed no evidence of allograft rejection. She was subsequently referred for coronary intervention. Due to concern of CTO being a sign of rapidly progressing CAV, it was decided to undergo revascularization of the RCA. Antegrade approach was performed with guidance from contralateral injections. Three overlapping drug-eluting stents were deployed proximally-distally using intravascular ultrasound guidance. Surveillance angiography nine months later showed patent RCA stents with no significant disease otherwise. Eighteen months later, angiography demonstrated CTO of the mid LAD and patent RCA stents with mild in-stent restenosis in the most distal RCA stent. The patient remained asymptomatic. Discussion: CAV develops in fifty percent of transplanted hearts within 10 years and requires close surveillance. In this case, revascularization of the RCA CTO resulted in maintaining graft function for at least two additional years as the development of LAD CTO may have resulted in graft failure had the RCA CTO not been intervened upon. CTO revascularization in CAV has the potential to prolong graft viability and delay the need for re-transplantation. Further studies related to CTO revascularization, especially in asymptomatic transplanted patients, are needed to understand the impact on morbidity and mortality in this patient population.