TCT-235 Efficacy of Bioresorbable Vascular Scaffold vs Drug-Eluting Stents After PCI: A GRADE-Assessed Systematic Review and Meta-Analysis of Randomised Controlled Trials

After two decades of research and development of biodegradable metallic materials, Mg-based, Fe-based and Zn-based biodegradable metals (BMs) had been widely studied by in vitro and in vivo biocompatibility testing. There were WE43 Mg alloy and Mg-Ca-Zn alloy bone screws being clinically used in Europe and China, Nitride Fe bioresorbable vascular scaffold being CE marked and clinically trailed in China, Zn-Mg-Fe alloy Maxillofacial bone screw being clinically trailed in China. For the mechanical strength viewpoint, the current Mg-based biodegradable metals is in generally below 350MPa and it can only be suitable for low load-bearing application in regenerative medicine, whereas the Zn-based biodegradable metals had been explored, with the Zn-Li based alloys exhibiting the tensile strength around 600MPa, close to that of the pure Ti and stainless steel, and is applicable for the medium load-bearing application in regenerative medicine. The Fe-based biodegradable metals had shown higher mechanical strength, but the majority of biometal society believe that Fe-based BMs is unsuitable for orthopaedic applications since element iron does not exist in the bone. In this work, we achieve significant bone ingrowth into Zn-based porous scaffolds with 90% porosity via osteoinmunomodulation. At microscale, an alloy incorporating 0.8 wt% Li is employed to create a eutectoid lamellar structure featuring the LiZn4 and Zn phases. This microstructure optimally balances high strength with immunomodulation effects. At mesoscale, surface pattern with nanoscale roughness facilitates filopodia formation and macrophage spreading. At macroscale, the isotropic minimal surface G unit exhibits a proper degradation rate with more uniform feature compared to the anisotropic BCC unit. In vivo, the G scaffold demonstrates a heightened efficiency in promoting macrophage polarization toward an anti-inflammatory phenotype, subsequently leading to significantly elevated osteogenic markers, increased collagen deposition, and enhanced new bone formation. In vitro, transcriptomic analysis reveals the activation of JAK/STAT pathways in macrophages via up regulating the expression of Il-4, Il-10, subsequently promoting osteogenesis.

Restenosis is the main cause of failure after stent implantation during angioplasty. The localized, sustained delivery of an antirestenotic drug may reduce smooth muscle cell (SMCs) proliferation and thereby limit neointimal hyperplasia. The aim of this study was to develop degradable sirolimus-eluting polymer coatings that can be applied on bioresorbable polymer-based scaffolds via an ultrasonic coating system. This is a novel approach because the detailed analysis of the coating procedure on bioresorbable polymeric scaffolds with the use of an ultrasonic system has not been reported thus far. It has been observed that the ultrasonic technique facilitates formation of a smooth coating, well-integrated with the scaffold. However, the drug dose is affected by the concentration of the coating solution and the number of layers. Therefore, these parameters can be used for tailoring the drug dose and release process. Although all types of the developed coatings provided sirolimus elution for at least 3 months, a more uniform, diffusion-controlled release profile was observed from coatings obtained from the 1.0% polymeric solution. The released drug showed antiproliferative activity against vascular SMCs, without any hemolytic or thrombogenic effects. The results of the study may be advantageous for further progress in the development and medical translation of polymeric vascular scaffolds with antirestenotic activity.

Polymer-based bioresorbable vascular scaffolds (BVS) have garnered significant attention in biomedical applications. Among various BVS, polycaprolactone (PCL)-based scaffolds exhibit excellent biocompatibility, flexibility, chemical stability, and controlled degradation. However, their low radial strength limits practical applicability. Moreover, most reported BVS require periodic postimplantation monitoring to enable early detection of in-stent restenosis and thrombosis. To overcome these limitations, we fabricate a carbon nanotube (CNT)-reinforced PCL BVS using a 3D printing process, enabling patient-specific customization while significantly improving mechanical strength and durability. The proposed PCL/CNT-based stent not only serves as a structural scaffold but also facilitate real-time vascular pressure monitoring by integrating a wireless LC capacitive pressure sensor. The LC pressure sensor is microfabricated using microelectromechanical systems (MEMS) technology and exhibits highly stable resonance characteristics. A key innovation is the integration of a supporting micropillar within the capacitor cavity, which minimizes structural deformation and ensures a stable capacitance response. Mechanical testing demonstrates that PCL/CNT stents achieve significantly higher radial force (0.1 N/mm) compared to pristine PCL (0.013 N/mm). The wireless sensor exhibits high sensitivity (49 kHz/mmHg) with minimal capacitance variation (±5%). In-vitro studies in a phantom experiment confirm stable resonance frequency fluctuations that accurately correlate with hemodynamic changes. This smart stent integrates biodegradable nanocomposites, 3D printing, and wireless sensing, providing a noninvasive platform for restenosis and thrombosis monitoring. It marks a significant advancement in cardiovascular implants, paving the way for personalized and proactive patient care.

The Mo-14Re alloy, a promising candidate material for bioresorbable vascular scaffolds.

A novel Internet of Medical Things framework for absorbing bioresorbable vascular scaffold towards healthcare monitoring based on improving YOLO paradigms

Endovascular revascularization of below-the-knee lesions is a crucial treatment for patients with chronic limb-threatening ischemia (CLTI). However, the optimal approach to revascularizing infrapopliteal arteries remains uncertain. This study aims to compare the safety and efficacy outcomes of various endovascular treatment modalities for infrapopliteal artery disease and provide an evidence-based update through a network meta-analysis. We performed a systematic literature search in MEDLINE, EMBASE, and the Cochrane Database for randomized controlled trials published between January 01, 2005, and January 12, 2025. The study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and was prospectively registered in PROSPERO database (CRD42022323480). The primary safety outcome was major adverse events defined as a composite of all-cause death, major amputation, and any re-intervention of the target limb at 30 days. The primary efficacy outcomes included freedom from composite of major amputation, target lesion occlusion, and clinically driven target lesion revascularization (CD-TLR) and primary patency defined as freedom from binary restenosis and CD-TLR at 6 months. The network meta-analysis was conducted in the frequentist framework using random effects model and conventional percutaneous transluminal angioplasty (PTA) as the reference intervention. Treatment effects were reported as odds ratio (OR) with 95% confidence interval (CI) compared with conventional PTA and interventions were ranked using P-scores. Twenty-three studies including 3091 patients treated with PTA, paclitaxel drug-coated balloons (DCB), drug-eluting stents (DES), bare metal stents (BMS), bioresorbable vascular scaffold (BVS), and atherectomy were included. There were no significant differences in the primary safety outcome between different treatment modalities. At 6 months, DCB, atherectomy with DCB, and DES produced the largest benefit for primary efficacy outcomes. DCB (OR, 3.68; 95% CI, 1.37-9.92) had a higher freedom from the primary composite, and atherectomy with DCB (OR, 7.65; 95% CI, 1.03-56.98) and DES (OR, 5.48; 95% CI, 1.54-19.49) had higher primary patency compared with PTA. At 12 months, the benefit of atherectomy with DCB was sustained for primary patency, and BVS was ranked first for freedom from the primary composite. There was no benefit of BMS compared with PTA at any timepoint. This network meta-analysis evaluating 7 endovascular treatment modalities provides evidence of improved efficacy outcomes with DCB, atherectomy with DCB, DES, and BVS compared with PTA for treating infrapopliteal lesions in patients with CLTI.Clinical ImpactLocal antiproliferative drug delivery, whether by balloon-expandable sirolimus/everolimus DES or paclitaxel DCB or everolimus BVS, is necessary to improve patency and efficacy outcomes for the treatment of infrapopliteal artery disease. Furthermore, combining atherectomy with drug delivery shows promising potential. Emerging endovascular targeted drug delivery therapies with limus-based DCB or scaffolds promise to provide greater drug transfer efficiency and a more effective therapeutic alternative that overcomes the limitations of metallic stents in one of the most challenging vascular beds.

D-28 | Bioresorbable vascular scaffolds vs drug eluting stents for patients with myocardial infarction

TCTAP C-119 Bioresorbable Vascular Scaffolds in Treating Left Mainstem Coronary Artery Disease: A First Long-Term Imaging Analysis

Coronary artery aneurysm (CAA) formation following bioresorbable vascular scaffold (BVS) implantation is a rare but serious complication with no clear treatment guidelines. We report the case of a 56-year-old man with coronary artery disease (CAD) and a chronic total occlusion (CTO) in the left anterior descending artery (LAD) underwent full revascularization with BVS in 2016. Seven years later, he experienced recurrent angina, and angiography revealed 80% stenosis in the proximal LAD and a large coronary aneurysm in the middle LAD. Optical coherence tomography (OCT) confirmed a 5.88 mm aneurysm, which was treated with a PK Papyrus covered stent, while the proximal LAD stenosis was addressed with a Resolute Onyx drug-eluting stent (DES). After six months of standard dual antiplatelet therapy (DAPT) followed by three months of single antiplatelet therapy (SAPT), the patient developed in-stent restenosis (ISR) in the covered stent. This was successfully treated with high-pressure balloon angioplasty and a drug-eluting balloon (DEB). At the nine-month follow-up, the patient remained symptom-free. This case highlights the utility of OCT in evaluating CAAs and guiding covered stent deployment, while prolonged DAPT may help reduce the risk of very late stent thrombosis and future ischemic events, though further studies are needed.

Effects of structural design on the mechanical performances of poly-L-lactic acid cardiovascular scaffolds using FEA and in vitro methods.

Despite the significant advancements in interventional cardiology, there is a need for new, metal-free bioresorbable stent systems that preserve the vasomotor function of the treated vessel and decrease the risk of restenosis associated with metal stents and the risk of thrombosis associated with first-generation bioresorbable scaffolds. The aim of this study was to assess the safety and efficacy of the MeRes100 bioresorbable scaffold in complex de novo and in-stent restenotic coronary lesions. We conducted a retrospective single-centre study that included 86 patients with coronary artery disease who had been implanted with a next-generation MeRes100 sirolimus-eluting bioresorbable vascular scaffold system and followed up to 12 months after the procedure. The scaffold was successfully delivered to the target lesion with satisfactory stent expansion in 98.84% of cases. Only one patient died, and the in-hospital mortality rate was as low as 1.16% (cardiac death). No cases of major adverse cardiac events, cardiac death, myocardial infarction, ischaemia-driven target lesion revascularisation, or scaffold thrombosis were reported during the follow-up. Our preliminary data suggest that the thin-strut sirolimus-eluting bioresorbable scaffold appears to be a clinically acceptable, safe, reliable and reproducible strategy to treat both de novo and in-stent restenotic coronary artery lesions. Long-term follow-up of a larger patient population is warranted.

Limus-based balloons, stents, and scaffolds are alternatives to paclitaxel-coated devices in peripheral endovascular treatment. This study aims to review contemporary evidence on the efficacy and safety of limus-coated devices in the treatment of lower extremity peripheral arterial disease (PAD). A systematic literature review was performed using PubMed, Web of Sciences, OvidSP, and EMBASE, according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Efficacy endpoints were primary patency (PP), freedom from clinically driven target lesion revascularization (CD-TLR) and Rutherford-Becker improvement; safety endpoints included target limb amputation and all-cause mortality. From a primary search of 453 articles between 27th June 2002 to 15th September 2024, 30 publications, among which were 27 prospective trials, 10 multicenter studies and 11 double-arm studies, with 2325 patients were analyzed. The numbers for above-the-knee (ATK) limus-balloons, stents, scaffolds and below-the-knee (BTK) limus-balloons, stents, scaffolds were 76, 333, 35, 55, 1445, 381 respectively. With a mean 12-month follow-up, PP for ATK lesions was 86.50% for sirolimus-coated balloons (SCB), 86.80% for sirolimus-eluting stents (SES), 72.60% for everolimus-eluting stents (EES), 86.20% for everolimus bioresorbable vascular scaffold (EBVS); whereas PP for BTK lesions was 72.60%, 73.20%, 71.60 and 83.80% respectively. Absence of CD TLR for ATK lesions was 96.50%, 95.50%, 87.60%, 89.20% respectively; meanwhile 84.90%, 75.80%, 87.70%, 94.30% for BTK lesions respectively. Rutherford-Becker improvement with 86.70%, 84.50%, 79.80 and 90.80% were seen in ATK lesions respectively, similarly, 76.50%, 81.90%, 79.50%, 92.30% respectively were observed in BTK lesions. Efficacy and clinical outcomes of SES, EES and EBVS in BTK lesions were significantly superior, where vascular complications had no proven significant difference regardless of lesion locations nor device types. Limus-coated/eluting balloons, stents, and scaffolds are safe adjuncts and potentially superior alternative in endovascular treatment for lower extremity PAD, especially well proven in BTK lesions. However, more statistically significant evidence is recommended to validate the long-term efficacy on ATK lesions and overall use of non-SES devices regardless of locations. Limus (siro-, zotaro-, evero-, bio-, amphi-, tacrolimus) have potent antiproliferative effects in atherosclerosis. This systematic review analyzes evidence for the efficacy and safety of limus devices (balloons, stents, and scaffolds) in the treatment of femoropopliteal and below-the-knee PAD. There were 5 single-arm studies with 309 patients on femoropopliteal disease, and 11 studies with 679 patients on below-the knee (BTK) diseases. The overall primary patency rate, significant freedom from target lesion revascularization and improvement in Rutherford-Becker classification were high. Certain limus devices have shown to be superior to non-limus devices. Limus scaffolds are new developments with promising short-term results.

PurposeTreatment of peripheral artery disease (PAD) in the region below the knee (BTK) is dissatisfying as failure of treated target lesions (TLF) is frequent and diagnostic imaging is often challenging. In the BTK-region metallic drug-eluting stents (mDES) yielded best results concerning primary patency (PP), but also annihilate signal in magnetic resonance angiography (MR-A). A recently introduced non-metallic drug eluting bioresorbable Tyrocore® vascular scaffold (deBVS), that offers an option for re-treatment of lesions due to its full degradation within 3–4 years after placement, was investigated with respect to its compatibility with MR-A to unimpededly depict previously treated target lesions.MethodsPatency of the deBVS in the BTK-region was assessed retrospectively using contrast enhanced MR-A of the lower limbs in patients with PAD of Lafontaine-grades II-IV (n = 19). Clinically driven MR-A censoring was triggered by an assumed target lesion failure (CD-TLF), which served to compute the probability of PP during the observation period of 5 years. Compatibility of this particular deBVS with MRI was additionally proven via in-vitro experiments.ResultsThe scaffold was found to be fully compatible with MRI. The normalised intra-luminal signal measured in MR-A increased significantly after successful deBVS-placement. The retrospective 5-years PP-probability was 0.87 (CI95%: [0.71,1.0]) with 2 stent-occlusions observed after 90 days. No major adverse events occurred.ConclusionAssessment of PAD in the BTK-region after placement of the Tyrocore®-deBVS using MRA is feasible. The promising high PP-probability after 5-years and the persistent full interpretability of treated target lesions by MR-A after stent-placement encourage further prospective assessment of this deBVS in treatment of PAD in the BTK-region.

Treatment of peripheral artery disease (PAD) in the region below the knee (BTK) is dissatisfying as failure of treated target lesions (TLF) is frequent and diagnostic imaging is often challenging. In the BTK-region metallic drug-eluting stents (mDES) yielded best results concerning primary patency (PP), but also annihilate signal in magnetic resonance angiography (MR-A). A recently introduced non-metallic drug eluting bioresorbable Tyrocore® vascular scaffold (deBVS), that offers an option for re-treatment of lesions due to its full degradation within 3-4 years after placement, was investigated with respect to its compatibility with MR-A to unimpededly depict previously treated target lesions. Patency of the deBVS in the BTK-region was assessed retrospectively using contrast enhanced MR-A of the lower limbs in patients with PAD of Lafontaine-grades II-IV (n = 19). Clinically driven MR-A censoring was triggered by an assumed target lesion failure (CD-TLF), which served to compute the probability of PP during the observation period of 5 years. Compatibility of this particular deBVS with MRI was additionally proven via in-vitro experiments. The scaffold was found to be fully compatible with MRI. The normalised intra-luminal signal measured in MR-A increased significantly after successful deBVS-placement. The retrospective 5-years PP-probability was 0.87 (CI95%: [0.71,1.0]) with 2 stent-occlusions observed after 90 days. No major adverse events occurred. Assessment of PAD in the BTK-region after placement of the Tyrocore®-deBVS using MRA is feasible. The promising high PP-probability after 5-years and the persistent full interpretability of treated target lesions by MR-A after stent-placement encourage further prospective assessment of this deBVS in treatment of PAD in the BTK-region.

Neointimal coverage and stent apposition, as assessed from intravascular optical coherence tomography (IVOCT) images, are crucial for optimizing percutaneous coronary intervention (PCI). Existing state-of-the-art computer algorithms designed to automate this analysis often treat lumen and stent segmentations as separate target entities, applicable only to a single stent type and overlook automation of preselecting which pullback segments need segmentation, thus limit their practicality. This study aimed for an algorithm capable of intelligently handling the entire IVOCT pullback across different phases of PCI and clinical scenarios, including the presence and coexistence of metal and bioresorbable vascular scaffold (BVS), stent types. We propose a multi-task deep learning model, named TriVOCTNet, that automates image classification/selection, lumen segmentation and stent struts segmentation within a single network by integrating classification, regression and pixel-level segmentation models. This approach allowed a single-network, single-pass implementation with all tasks parallelized for speed and convenience. A joint loss function was specifically designed to optimize each task in situations where each task may or may not be present. Evaluation on 4,746 images achieved classification accuracies of 0.999, 0.997, and 0.998 for lumen, BVS, and metal stent features, respectively. The lumen segmentation performance showed a Euclidean distance error of 21.72μm and Dice's coefficient of 0.985. For BVS struts segmentation, the Dice's coefficient was 0.896, and for metal stent struts segmentation, the precision was 0.895 and sensitivity was 0.868. TriVOCTNet highlights its clinical potential due to its fast and accurate results, and simplicity in handling all tasks and scenarios through a single system.

Early and Late Outcomes With the Absorb Bioresorbable Vascular Scaffold: Final Report From the ABSORB Clinical Trial Program.

Moving away from metal: Step toward the future with bioresorbable vascular scaffolds and novel antiproliferative agents.

Abstract At present, there are no bioresorbable systems available for the treatment of aortic coarctation in pediatric patients. However, experience with off-label used systems and knowledge of bioresorbable scaffolds in other applications suggest potential benefits. While stenting techniques are typically preferred for older children, there have been encouraging reports regarding their use in newborns and very young infants recently. Bioresorbable scaffolds could potentially close the technological gap in this area and serve as a bridge therapy for non-operable patients. This work identifies geometric and loading aspects in the light of current literature to improve the growth-responsive development of new scaffolds for the treatment of congenital heart diseases with pediatric-specific characteristics.

Five-year clinical outcomes of STEMI patients treated with a pre-specified bioresorbable vascular scaffold implantation technique: Final results of the BVS STEMI STRATEGY-IT