Late acquired coronary aneurysm and restenosis after bioresorbable vascular scaffold implantation: a case report.

Background: Although the technology of bioresorbable vascular scaffold (BVS) aroused the peak of interest a few years ago and currently remains available only as part of experimental research, patients who have had BVS implanted should be still carefully monitored to detect possible long-term complications. Case summary: We present the case of a 47-year-old man who had received BVS implantation for ST-segment elevation myocardial infarction. Six years later, computed tomography coronary angiography (CTCA) demonstrated in-segment restenosis in between two newly formed coronary aneurysms at the site of the implanted BVS. The patient received successful optical coherence tomography-guided percutaneous intervention with a new metallic drug-eluting stent implantation. Discussion: Our case demonstrates that coronary aneurysms can be well characterized with CTCA and are often incidentally discovered as they cause no symptoms. The incidence of coronary aneurysm at the site of a previously implanted BVS is not defined, and little is known about the pathophysiology and evolution of these lesions. Therefore, the decision to proceed with conservative management or intervention must be tailored to the clinical conditions of the patient, the anatomy, the rapidity of growth, and the possible thrombotic burden.

Safety and efficacy of everolimus-eluting bioresorbable vascular scaffold for cardiac allograft vasculopathy (CART).

BACKGROUND: Cardiac allograft vasculopathy (CAV) is still the main drawback of heart transplantation (HTx) and percutaneous coronary intervention (PCI) is a palliative measure because of the high incidence of failure. OBJECTIVE: This study aimed to investigate the safety and efficacy of bioresorbable scaffolds (BRSs) as potential novel therapeutic tool for the treatment of coronary stenoses in CAV. METHODS: This is a multicenter, single-arm, prospective, open-label study (CART, NCT02377648), that included patients affected by advanced CAV treated with PCI and second-generation ABSORB BRS (Abbott Vascular). The primary endpoint was the incidence of 12-month angiographic in-segment scaffold restenosis (ISSR). Secondary endpoints were the incidence of major adverse cardiac events (MACEs) at 12- and 36-month follow-up and the incidence of ISSR at 36 months. A paired intracoronary imaging analysis at baseline and follow-up was also performed. RESULTS: Between 2015 and 2017 35 HTx patients were enrolled and treated for 44 coronary lesions with 51 BRSs. The primary endpoint occurred in 13.5% of the lesions (5/37), with a cumulative ISSR rate up to 3 years of 16.2% (6/37). Angiographic lumen loss was 0.40 ± 0.62 mm at 12 months and 0.53 ± 0.57 mm at 36 months. Overall survival rate was 91.4% and 74.3%, and MACEs incidence 14.2% and 31.4% at 12 and 36 months, respectively. At the paired intracoronary imaging analysis, a significant increase of the vessel external elastic membrane area in the treated segment and some progression of CAV proximally to the BRS were detected. CONCLUSIONS: BRS-based PCI for the treatment of CAV is feasible and safe, with an ISSR incidence similar to what reported in retrospective studies with drug-eluting stents.

Impact of post-implantation time on bioresorbable vascular scaffold outcomes for type C versus non-type C coronary lesions: A longer-term study.

BACKGROUND: We have demonstrated that bioresorbable vascular scaffold (BVS) for ACC/AHA type C lesions was associated with higher risks of long-term target lesion revascularization (TLR) and target lesion failure (TLF). We determined the specific time after which higher risks of BVS for type C lesions are reduced in a longer-term follow-up. METHODS: We analyzed data of 457 patients (59 ± 12 years, 87% male) with 714 BVS implanted for 529 lesions and a median follow-up of 56.4 (48.6-62.6) months. Patients with BVS for at least one type C lesion (N = 177) at index intervention and all non-type C lesions (N = 280) were compared for TLF (cardiac death, target vessel myocardial infarction, TLR). We specified the interactions between the non-type C versus type C group and the event-free survival times dichotomized at 24, 30, 32, 33, 36, and 39 months respectively. RESULTS: The type C group had more multivessel disease (86% versus 65%, p < 0.001), left anterior descending artery treated (68% versus 53%, p = 0.002), intravascular imaging used (48% vs. 25%, p < 0.001), and BVS (2.3 ± 0.9 vs. 1.1 ± 0.3, p < 0.001) implanted with a longer total length (57 ± 21 vs. 29 ± 8 mm, p < 0.001). The TLR or TLF was higher (both log-rank p < 0.05) in the type C than in the non-type C group. However, the risks of TLR (hazard ratio: 3.6, 95% CI = 1.1-11.6) and TLF (hazard ratio: 3.8, 95% CI = 1.2-12.1) for type C lesions only remained higher until 24 months post-BVS implantation. CONCLUSION: BVS provides a longer-term advantage, particularly for type C lesions with the majority requiring long stenting.

Bioresorbable Vascular Scaffolds: A Disappearing Technology, But Should We Let It Vanish?

Absorb bioresorbable vascular scaffolds were designed to overcome the limitations imposed by drug-eluting stents; however, the Absorb BVS showed a 2% very late thrombosis rate. Suboptimal implantation technique has been proposed as a mechanism for the higher BVS thrombosis rate; one posthoc analysis suggested adequate pre- and postdilation in addition to proper sizing could reduce BVS thrombosis rates by 70%. This case acts as a proof of concept demonstrating advantages of BVS, namely, the ability to image the target vessel non-invasively and revascularize percutaneously or surgically if required. We advocate continued research and development in this technology given the attractive advantages, particularly in younger patients who are likely to require future coronary intervention and imaging.

Preclinical Evaluation of an Everolimus-Eluting Bioresorbable Vascular Scaffold Via a Long-Term Rabbit Iliac Artery Model.

BACKGROUND: Biodegradable poly (l-lactic acid) (PLLA), a bio safe polymer with a large elastic modulus, is widely used in biodegradable medical devices. However, because of its poor mechanical properties, a PLLA strut must be made twice as thick as a metal strut for adequate blood vessel support. Therefore, the mechanical properties of a drug-eluting metal-based stents (MBS) and a bioresorbable vascular scaffolds (BVS) were evaluated and their safety and efficacy were examined via a long-term rabbit iliac artery model. METHODS: The surface morphologies of the MBSs and BVSs were investigated via optical and scanning electron microscopy. An everolimus-eluting (EE) BVS or an EE-MBS was implanted into rabbit iliac arteries at a 1.1:1 stent-to-artery ratio. Twelve months afterward, stented iliac arteries from each group were analyzed via X-ray angiography, optical coherence tomography (OCT), and histopathologic evaluation. RESULTS: Surface morphology analysis of the EE coating on the MBS confirmed that it was uniform and very thin (4.7 µm). Comparison of the mechanical properties of the EE-MBS and EE-BVS showed that the latter outperformed the former in all aspects (radial force (2.75 vs. 0.162 N/mm), foreshortening (0.24% vs. 1.9%), flexibility (0.52 vs. 0.19 N), and recoil (3.2% vs. 6.3%). At all time points, the percent area restenosis was increased in the EE-BVS group compared to the EE-MBS group. The OCT and histopathological analyses indicate no significant changes in strut thickness. CONCLUSION: BVSs with thinner struts and shorter resorption times should be developed. A comparable long-term safety/efficacy evaluation after complete absorption of BVSs should be conducted.

Safety and Efficacy of Everolimus-Eluting Bioresorbable Vascular Scaffold Versus Second-Generation Drug-Eluting Stents in Real-World Practice.

BACKGROUND: The risk of device thrombosis and device-oriented clinical outcomes with bioresorbable vascular scaffold (BVS) was reported to be significantly higher than with contemporary drug-eluting stents (DESs). However, optimal device implantation may improve clinical outcomes in patients receiving BVS. The current study evaluated mid-term safety and efficacy of Absorb BVS with meticulous device optimization under intravascular imaging guidance. METHODS: The SMART-REWARD and PERSPECTIVE-PCI registries in Korea prospectively enrolled 390 patients with BVS and 675 patients with DES, respectively. The primary endpoint was target vessel failure (TVF) at 2 years and the secondary major endpoint was patient-oriented composite outcome (POCO) at 2 years. RESULTS: Patient-level pooled analysis evaluated 1,003 patients (377 patients with BVS and 626 patients with DES). Mean scaffold diameter per lesion was 3.24 ± 0.30 mm in BVS group. Most BVSs were implanted with pre-dilatation (90.9%), intravascular imaging guidance (74.9%), and post-dilatation (73.1%) at proximal to mid segment (81.9%) in target vessel. Patients treated with BVS showed comparable risks of 2-year TVF (2.9% vs. 3.7%, adjusted hazard ratio [HR], 1.283, 95% confidence interval [CI], 0.487-3.378, P = 0.615) and 2-year POCO (4.5% vs. 5.9%, adjusted HR, 1.413, 95% CI, 0.663-3.012, P = 0.370) than those with DES. The rate of 2-year definite or probable device thrombosis (0.3% vs. 0.5%, P = 0.424) was also similar. The sensitivity analyses consistently showed comparable risk of TVF and POCO between the 2 groups. CONCLUSION: With meticulous device optimization under imaging guidance and avoidance of implantation in small vessels, BVS showed comparable risks of 2-year TVF and device thrombosis with DES. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02601404, NCT04265443.

Efficacy and Safety of Absorb Everolimus-Eluting Bioresorbable Vascular Scaffold in Peripheral Artery Disease: A Single-Arm Meta-Analysis.

PURPOSE: This study aimed to evaluate the benefits and risks of patients with peripheral artery disease (PAD) treated with Absorb everolimus-eluting bioresorbable vascular scaffold (BVS) by analyzing all the published studies on the clinical characteristics of patients with PAD. MATERIALS AND METHODS: PubMed, Embase, and the Cochrane Library were searched for relevant studies. Efficacy, safety, and basic characteristics were analyzed. RESULTS: Four studies were included in meta-analysis, including a total number of 155 patients with PAD. The pooled overall primary patency, freedom from target lesion revascularization (TLR), symptom resolution, and wound healing were 90%, 96%, 94%, and 86%, respectively. The pooled perioperative complication and all-cause mortality were 4% and 9%, respectively. Preoperative total occlusion was detected in 43 of 192 lesions (22%). The mean lesion length was 27.26 mm. In terms of comorbidities, the pooled percentage of hypertension, hyperlipidemia, diabetes mellitus, coronary artery disease, chronic kidney disease history, and smoking were 65%, 74%, 49%, 43%, 20%, and 57%, respectively. CONCLUSION: Among these studies, hypertension, hyperlipidemia, and diabetes mellitus were the most common comorbidities in patients with PAD. The Absorb everolimus-eluting BVS was safe and showed the favorable clinical outcomes in both patency and TLR, especially in infrapopliteal disease with heavy calcification. The conclusions of this meta-analysis still needed to be verified by more relevant studies with more careful design, more rigorous execution, and larger sample size.

Dissections after bioresorbable vascular scaffold implantation in the POLAR ACS Registry.

Introduction: Percutaneous coronary intervention (PCI) is a common method of treatment for patients with coronary artery disease. One of the most common complications during the PCI procedure is coronary artery dissection. It usually requires an additional action to assure the patency of the treated vessel. Aim: The aim of the publication is to describe the occurrence of coronary artery dissection after bioresorbable vascular scaffold (BVS) implantation. This selected type of PCI procedure is especially interesting because precise target vessel measurement before BVS implantation is required for optimal determination of scaffold size. Material and methods: Based on angiographic data gathered in the POLAR ACS Registry, we assessed the frequency of dissections, their localization, and severity. Based on data regarding patients' demographic, clinical status, and details regarding treatment strategy, the factors that could have an influence on the dissection occurrence were identified. Results: A group of 100 patients included in the analyses. Group A consisted of 9 patients. This group was defined as patients in whom the significant dissection occurred after the BVS implantation. Group B comprised 91 patients. Both groups were very similar according to demographic data. The frequency of predilatation was similar; post-dilatation was performed more often in group A but without statistical significance. The presence of calcification in the target lesion was an independent factor of dissection during the index PCI procedure. Conclusions: The occurrence of significant dissection can be effectively treated, and the good angiographic results of this treatment immediately after the initial procedure translate into good clinical results in longer follow-up.

Five-year clinical outcomes using the bioresorbable vascular scaffold: Insights from the FRANCE ABSORB registry.

BACKGROUND: Randomized trials comparing the first-generation absorb bioresorbable vascular scaffold (BVS) (Abbott Vascular, Santa Clara, CA, USA) with a drug-eluting stent showed a moderate but significant increase in the rate of 3-year major adverse cardiac events and scaffold thrombosis, followed by a decrease in adverse events after 3 years. AIM: The objective of this study was to assess the 5-year outcomes of patients treated with at least one absorb BVS and included in the FRANCE ABSORB registry. METHODS: All patients treated in France with an absorb BVS were prospectively included in a large nationwide multicentre registry. The primary efficacy outcome was the occurrence of 5-year major adverse cardiac events. Secondary efficacy outcomes were the rates of 5-year target vessel revascularization and definite/probable scaffold thrombosis. RESULTS: Between September 2014 and April 2016, 2,070 patients were included in 86 centres (mean age 55±11 years; 80% men; 49% with acute coronary syndrome). The rates of 1-, 3- and 5-year major adverse cardiac events were 3.9%, 9.4% and 12.1%, respectively (including cardiac death in 2.5% and target vessel revascularization in 10.4%). By multivariable analysis, diabetes, oral anticoagulation, the use of multiple Absorb BVSs and the use of a 2.5mm diameter absorb BVS were associated with 5-year major adverse cardiac events. The rates of 1-, 3- and 5-year definite/probable scaffold thrombosis were 1.5%, 3.1% and 3.6%, respectively. By multivariable analysis, older age, diabetes, anticoagulation at discharge and the use of a 2.5mm diameter absorb BVS were associated with 5-year scaffold thrombosis. CONCLUSIONS: Absorb BVS implantation was associated with low rates of 1-year major adverse cardiac events, which increased significantly at 3-year follow-up. There was a clear decrease in the rates of scaffold thrombosis and major adverse cardiac events after 3 years.

Quality of life of patients with coronary heart disease treated with the bioresorbable vascular scaffold (ABSORB™): 2-year results from the GABI-R-registry.

BACKGROUND: Numerous studies have reported clinical endpoints following coronary revascularization using bioresorbable vascular scaffolds (BVS), while information about the impact on health-related quality of life is sparse. In this analysis of the German-Austrian ABSORB RegIstRy, the 2 year results concerning quality of life development in a large cohort of patients treated with BVS were reported. METHODS: Data were collected at baseline as well as 30 days, 6 and 24 months after coronary revascularization using BVS. The EQ-5D score, EQ visual analogue scale (VAS) and Seattle Angina Questionnaire (SAQ) were determined for each time point. Patients were categorized according to the indication for coronary revascularization [acute coronary syndrome (ACS), stable angina pectoris (SAP), silent myocardial ischemia (SMI), or other]. Binary logistic regression analysis was performed to determine factors that predict above-average scores two years after implantation. RESULTS: Data from 1317 patients in 88 centres were included. Reasons for revascularization were: ACS (n = 643), SAP (n = 443), SMI (n = 52), and other (n = 179). Mean EQ-5D was significantly increased after six months, while a value comparable to baseline was found two years after implantation. EQ VAS and four of five dimensions of SAQ were significantly improved over baseline at all follow-up surveys. Particularly strong improvements were seen in SAQ scores angina frequency and quality of life. Binary regressions showed different statistically significant predictors in the respective models. CONCLUSIONS: Following coronary revascularization with BVS strong decrease in self-reported angina frequency and increase of self-reported quality of life were observed with continuous improvements over two years of follow-up. Trial registration ClinicalTrials.gov Identifier: NCT02066623.

Bioresorbable stents: Is the game over?

Bioresorbable scaffolds (BRS) emerged as an alternative to conventional stents with a fundamental idea, to avoid a permanent metallic cage with all its harmful effects on the vessel. The Absorb BVS was the first widely studied device with the promising concept of performing a percutaneous coronary intervention, giving the necessary initial support to maintain vessel integrity and avoid acute vessel thrombosis. After a period, complete resorption of the device without leaving in the vessel any metallic structure would theoretically offer several benefits as the reduction of the inflammatory response and recovering normal vasomotor function, recovering access of jailed side-branches and segments for surgical revascularization, and the reduction of very late stent thrombosis derived from late acquired malapposition. However, cumulative evidence from the different absorb randomized trials (ABSORB II, ABSORB III, ABSORB China, ABSORB Japan) raised significant concerns, due to an elevated rate of scaffold thrombosis, target lesion failure and target vessel failure, when compared to contemporary everolimus drug-eluting stents. Several mechanisms arose explaining scaffold failure; some were strictly related to the device itself, and others related to the operator and the lesion itself. Newer generation BRS are under development targeting the main limitations of the ABSORB BVS, mainly focusing on reducing strut thickness, improving the mechanical structure with faster resorption times, and a better crossing profile. The story of BRS is not over yet, with ongoing refinements in the quest for the ideal stent.

Lesion impacts on long-term outcomes in patients implanted with bioresorbable vascular scaffold.

BACKGROUND: Bioresorbable vascular scaffold (BVS) had been implanted to several kinds of complex coronary lesions in real-world practice. We tested if long-term outcomes of BVS for complex lesions would be worse than that for relatively simple lesions. METHODS: We analyzed 457 patients (59 ± 12 years, 87% male) with 714 BVS implanted for their 529 lesions and median follow-up of 32.7 (26.8-39.3) months. Complex group (N = 284) was defined as those with BVS for acute coronary syndrome, chronic total occlusion, bifurcation/ostial lesions, instent restenosis/hybrid with metallic stents, diffuse lesions (overlapped by 2 BVS with each â‰§ 18 mm), venous graft/left main lesions, or lesions after rotablation. We compared their outcomes with the remaining 173 patients as non-complex group. RESULTS: The complex group had more chronic kidney disease (7% vs. 2%), multivessel disease (78% vs. 65%), use of intravascular imaging (40% vs. 23%), and more BVS (1.8 ± 0.9 vs. 1.1 ± 0.3) with longer total lengths (47 ± 22 vs. 29 ± 8 mm) implanted than non-complex group (all p < 0.05). However, the long-term target lesion revascularization (TLR) or target lesion failure (TLF) was similar (log rank p > 0.05) between the two groups. Multivariate Cox regression analyses showed BVS for ACC/AHA type C lesions was independently associated with higher risks of TLR (hazard ratio: 2.7, 95% CI = 1.1-6.6) and TLF (hazard ratio: 2.6, 95% CI = 1.1-6.3). CONCLUSION: Comparable outcomes were found between BVS for complex and non-complex lesion category. However, higher risks of TLR and TLF for type C lesions still suggested the prognostic impact of lesion complexity on long-term outcomes of BVS.

Automated segmentation of metal stent and bioresorbable vascular scaffold in intravascular optical coherence tomography images using deep learning architectures.

Percutaneous coronary intervention (PCI) with stent placement is a treatment effective for coronary artery diseases. Intravascular optical coherence tomography (OCT) with high resolution is used clinically to visualize stent deployment and restenosis, facilitating PCI operation and for complication inspection. Automated stent struts segmentation in OCT images is necessary as each pullback of OCT images could contain thousands of stent struts. In this paper, a deep learning framework is proposed and demonstrated for the automated segmentation of two major clinical stent types: metal stents and bioresorbable vascular scaffolds (BVS). U-Net, the current most prominent deep learning network in biomedical segmentation, was implemented for segmentation with cropped input. The architectures of MobileNetV2 and DenseNet121 were also adapted into U-Net for improvement in speed and accuracy. The results suggested that the proposed automated algorithm's segmentation performance approaches the level of independent human obsevers and is feasible for both types of stents despite their distinct appearance. U-Net with DenseNet121 encoder (U-Dense) performed best with Dice's coefficient of 0.86 for BVS segmentation, and precision/recall of 0.92/0.92 for metal stent segmentation under optimal crop window size of 256.

Clinical presentation does not affect acute mechanical performance of the Novolimus-eluting bioresorbable vascular scaffold as assessed by optical coherence tomography.

INTRODUCTION: Initial trials of bioresorbable vascular scaffolds (BVS) have mostly excluded patients presenting with acute coronary syndrome (ACS). However, these patients might benefit from a BVS platform, in particular as they are often younger and have been less frequently treated than patients with chronic disease. AIM: To compare the acute performance of a Novolimus eluting BVS in ACS and non-ACS patients using optical coherence tomography (OCT) in patients presenting with acute or chronic coronary syndrome. MATERIAL AND METHODS: The final OCT pullback of 79 patients (34 with ACS, 45 non-ACS) was analysed at 1-mm intervals. The following indices were calculated: mean and minimal area, residual area stenosis, incomplete strut apposition, tissue prolapse, eccentricity index, symmetry index, strut fracture, and edge dissection. RESULTS: OCT showed a minimum lumen area (non-ACS vs. ACS) of 6.2 ±2.1 vs. 5.6 ±1.5 mm2 (p = 0.21). Mean residual area stenosis was 14.5% vs. 19.5% (p = 0.39). The mean eccentricity index did not differ significantly (0.78 ±0.13 vs. 0.78 ±0.06; p = 0.42). There was a non-significant tendency for more fractures in the non-ACS group (22.2% vs. 5.9%; p = 0.07). Prolapse area was comparable (4.4 ±7.4 mm2 vs. 5.2 ±10.9 mm2; p = 0.62). CONCLUSIONS: This is the first study to investigate the acute mechanical performance of a Novolimus-eluting BVS in patients with different clinical presentations using OCT. We found that clinical presentation did not determine acute mechanical performance as assessed by the final OCT pullback. There was evidence of more mechanical complications in terms of fractures and a higher percentage of incomplete strut apposition in the group of patients with chronic coronary syndrome.

Interaction of Poly L-Lactide and Tungsten Disulfide Nanotubes Studied by in Situ X-ray Scattering during Expansion of PLLA/WS2NT Nanocomposite Tubes.

In situ synchrotron X-ray scattering was used to reveal the transient microstructure of poly(L-lactide) (PLLA)/tungsten disulfide inorganic nanotubes (WS2NTs) nanocomposites. This microstructure is formed during the blow molding process ("tube expansion") of an extruded polymer tube, an important step in the manufacturing of PLLA-based bioresorbable vascular scaffolds (BVS). A fundamental understanding of how such a microstructure develops during processing is relevant to two unmet needs in PLLA-based BVS: increasing strength to enable thinner devices and improving radiopacity to enable imaging during implantation. Here, we focus on how the flow generated during tube expansion affects the orientation of the WS2NTs and the formation of polymer crystals by comparing neat PLLA and nanocomposite tubes under different expansion conditions. Surprisingly, the WS2NTs remain oriented along the extrusion direction despite significant strain in the transverse direction while the PLLA crystals (c-axis) form along the circumferential direction of the tube. Although WS2NTs promote the nucleation of PLLA crystals in nanocomposite tubes, crystallization proceeds with largely the same orientation as in neat PLLA tubes. We suggest that the reason for the unusual independence of the orientations of the nanotubes and polymer crystals stems from the favorable interaction between PLLA and WS2NTs. This favorable interaction leads WS2NTs to disperse well in PLLA and strongly orient along the axis of the PLLA tube during extrusion. As a consequence, the nanotubes are aligned orthogonally to the circumferential stretching direction, which appears to decouple the orientations of PLLA crystals and WS2NTs.

Comparison Between Bare-Metal Stents, First-Generation Drug-Eluting Stents, and Bioresorbable Vascular Scaffolds.

BACKGROUND: The long-term clinical outcomes after bioresorbable vascular scaffold (BVS) implantation have been extensively compared with second-generation drug-eluting stent (DES) implantation, but not with bare-metal stent (BMS) or first-generation DES options. OBJECTIVE: To compare the major adverse cardiovascular event (MACE) rates after implantation of BVS, first-generation DES, and BMS. METHODS: This was a single-center observational study based on a registry of percutaneous coronary intervention (PCI). The primary endpoint was MACE at 3 years, defined as a composite endpoint of death, non-fatal myocardial infarction, and target-vessel revascularization. RESULTS: A total of 170 consecutive patients who underwent PCI with implantation of everolimus-eluting BVS (Absorb; Abbott Cardiovascular) between 2014 and 2017 were compared with a control group of 622 patients implanted with BMS and 604 patients implanted with first-generation DES from 2001 to 2005. In adjusted analysis, DES had a lower risk of MACE at 3 years compared with BMS (adjusted odds ratio [OR], 0.58; 95% confidence interval [CI], 0.41-0.81; P<.01), while BVS had a similar risk of MACE compared with BMS (adjusted OR, 0.91; 95% CI, 0.55-1.52; P=.72). When compared with DES, BVS had a similar risk of MACE (adjusted OR, 1.45; 95% CI, 0.83-2.53; P=.19). CONCLUSIONS: In patients with BVS implantation, the risk of the composite outcome of MACE at 3 years was not significantly different when compared with patients with BMS or first-generation DES implantation.

Modulated molecular markers of restenosis and thrombosis byin-vitrovascular cells exposed to bioresorbable scaffolds.

Drug-eluting bioresorbable vascular scaffolds (BVSs) have emerged as a potential breakthrough for the treatment of coronary artery stenosis, providing mechanical support and drug delivery followed by complete resorption. Restenosis and thrombosis remain the primary limitations in clinical use. The study aimed to identify potential markers of restenosis and thrombosis analyzing the vascular wall cell transcriptomic profile modulation triggered by BVS at different values of shear stress (SS). Human coronary artery endothelial cells and smooth muscle cells were cultured under SS (1 and 20 dyne cm-2) for 6 h without and with application of BVS and everolimus 600 nM. Cell RNA-Seq and bioinformatics analysis identified modulated genes by direct comparison of SS conditions and Gene Ontology (GO). The results of different experimental conditions and GO analysis highlighted the modulation of specific genes as semaphorin 3E, mesenchyme homeobox 2, bone morphogenetic protein 4, (heme oxygenase 1) and selectin E, with different roles in pathological evolution of disease. Transcriptomic analysis of dynamic vascular cell cultures identifies candidate genes related to pro-restenotic and pro-thrombotic mechanisms in anin-vitrosetting of BVS, which are not adequately contrasted by everolimus addition.

Intravascular ultrasound predictors of long-term outcomes following ABSORB bioresorbable scaffold implantation: A pooled analysis of the ABSORB III and ABSORB Japan trials.

BACKGROUND: The long-term prognostic impact of IVUS findings following Absorb BVS implantation remains uncertain. This study aimed to identify the IVUS predictors of long-term clinical outcomes following ABSORB bioresorbable vascular scaffold (BVS) implantation from the pooled IVUS substudy cohorts of the ABSORB III and Japan trials. METHODS: A total of 298 lesions in 286 patients were enrolled with 2:1 randomization to ABSORB BVS vs. cobalt-chromium everolimus-eluting stents. This sub-analysis included 168 lesions of 160 patients in the Absorb arm whose post-procedural quantitative IVUS were available. The primary endpoint of this analysis was device-oriented composite endpoint (DOCE) of target lesion failure, including cardiac death, target vessel-related myocardial infarction, or ischemia-driven target lesion revascularization. The median follow-up duration was 4.9 [3.1-5.0] years. RESULTS: During follow-up, DOCE occurred in 10.1% of lesions treated with Absorb BVS. Among several post-procedural IVUS indices associated with DOCE, non-uniform device expansion (defined as uniformity index = minimum / maximum device area) (hazard ratio 0.47 per 0.1 increase [95%CI 0.28 to 0.77]; p = 0.003) and residual reference plaque burden (hazard ratio 4.01 per 10% increase [95%CI 1.50 to 10.77]; p = 0.006) were identified as independent predictors of DOCE by Cox multivariable analysis. CONCLUSIONS: Nonuniform device expansion and substantial untreated residual plaque in reference segments were associated with long-term adverse events following BVS implantation. Baseline imaging to identify the appropriate device landing zone and procedural imaging to achieve uniform device expansion if possible (e.g. through post-dilatation) may improve clinical outcomes of BVS implantation. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01751906 (ABSORB III); NCT01844284 (ABSORB Japan).

Restenosis of a drug eluting stent on the previous bioresorbable vascular scaffold successfully treated with a drug-coated balloon: A case report.

BACKGROUND: The in-stent restenosis (ISR) rates are reportedly inconsistent despite the increased use of second-generation drug eluting stent (DES). Although bioresorbable vascular scaffold (BVS) have substantial advantages with respect to vascular restoration, the rate of scaffold thrombosis is higher with BVS than with DES. Optimal treatment strategies have not been established for DES-ISR to date. CASE SUMMARY: We report on a case of a 60-year-old man patient with acute coronary syndrome. He had a history of ST-segment elevation myocardial infarction associated with very late scaffold thrombosis and treated with a DES. Coronary angiography revealed significant stenosis, suggesting DES-ISR on the previous BVS. Optical coherence tomography (OCT) identified a plaque rupture and a disrupted scaffold strut in the neointimal proliferation of DES. To treat the DES-ISR on the previous BVS, we opted for a drug-coated balloon (DCB) after a balloon angioplasty using a semi-compliant and non-compliant balloon. The patient did not experience adverse cardiovascular events on using a DCB following the use of intensive dual antiplatelet therapy and statin for 24 mo. CONCLUSION: This case highlights the importance of OCT as an imaging modality for characterizing the mechanism of target lesion failure. The use of a DCB following the administration of optimal pharmacologic therapy may be an optimal strategy for the treatment and prevention of recurrent BVS thrombosis and DES-ISR.

Mid-term outcomes of an everolimus-eluting bioresorbable vascular scaffold in patients with below-the-knee arterial disease: A pooled analysis of individual patient data.

Previous studies on everolimus-eluting bioresorbable vascular scaffolds (BVS) have shown promising 1-year primary patency rates in infrapopliteal arteries. Literature from large cohorts on long-term outcomes with the infrapopliteal Absorb BVS (Abbott Vascular) is lacking. The aim of this study is to pool published and unpublished data to provide a more precise estimate of the 24-month outcomes of Absorb BVS for the treatment of infrapopliteal disease. For the pooled analysis, updated original and newly collected data from three cohorts on treatment with the Absorb BVS for de novo infrapopliteal lesions were combined. The primary endpoint was freedom from restenosis. Secondary endpoints were freedom from clinically driven target lesion revascularization (CD-TLR), major amputation and survival. The pooled analysis included a total of 121 patients with 161 lesions, treated with 189 Absorb BVS in 126 limbs. The mean age of the patients was 73 years, 57% had diabetes mellitus, and 75% were classified as Rutherford-Becker class 5 or 6. Of the 161 lesions, 101 (63%) were calcified and 36 (22%) were occlusions. Successful deployment was achieved with all scaffolds. Freedom from restenosis was 91.7% and 86.6% at 12 and 24 months, respectively, and freedom from CD-TLR was 97.2% and 96.6%. Major amputation occurred in 1.6% of the limbs. Overall survival was 85% at 24 months. In conclusion, this pooled analysis represents the largest reported analysis of mid-term results of the Absorb BVS for the management of chronic limb-threatening ischemia. At 24 months, the Absorb BVS was safe with promising clinical outcomes for the treatment of infrapopliteal disease.