Evaluation of the second generation of a bioresorbable everolimus-eluting vascular scaffold for the treatment of de novo coronary artery stenosis: 12-month clinical and imaging outcomes

Revolutionizing Cardiovascular Frontiers: A Dive Into Cutting-Edge Innovations in Coronary Stent Technology

Plain balloon angioplasty was the initial method used to enlarge the intracoronary lumen size. However, it was linked to acute coronary closure due to early vessel recoil. This led to the invention of coronary stents, which offer mechanical support to open and maintain the vascular lumen. Nevertheless, the metallic scaffold introduced other issues, such as thrombosis and restenosis caused by neointimal proliferation. To address these concerns, polymers were employed to cover the scaffold, acting as drug reservoirs and regulators for controlled drug release. The use of polymers prevents direct contact between blood and metallic scaffolds. Drugs within the stent were incorporated to inhibit proliferation and expedite endothelialization in the healing process. Despite these advancements, adverse effects still arise due to the inflammatory reaction caused by the polymer material. Consequently, resorbable polymers and scaffolds were later discovered, but they have limitations and are not universally applicable. Various scaffold designs, thicknesses, materials, polymer components, and drugs have their own advantages and complications. Each stent generation has been designed to address the shortcomings of the preceding generation, yet new challenges continue to emerge. Conflicting data regarding the long-term safety and efficacy of coronary stents, especially in the extended follow-up, further complicates the assessment.

A new resorbable magnesium scaffold for de novo coronary lesions (DREAMS 3): one-year results of the BIOMAG-I first-in-human study

BACKGROUND

The third-generation coronary sirolimus-eluting magnesium scaffold, DREAMS 3G, is a further development of the DREAMS 2G (commercial name Magmaris), aiming to provide performance outcomes similar to drug-eluting stents (DES).

AIMS

The BIOMAG-I study aims to assess the safety and performance of this new-generation scaffold.

METHODS

This is a prospective, multicentre, first-in-human study with clinical and imaging follow-up scheduled at 6 and 12 months. The clinical follow-up will continue for 5 years.

RESULTS

A total of 116 patients with 117 lesions were enrolled. At 12 months, after completion of resorption, in-scaffold late lumen loss was 0.24±0.36 mm (median 0.19, interquartile range 0.06-0.36). The minimum lumen area was 4.95±2.24 mm² by intravascular ultrasound and 4.68±2.32 mm² by optical coherence tomography. Three target lesion failures were reported (2.6%, 95% confidence interval: 0.9-7.9), all clinically driven target lesion revascularisations. Cardiac death, target vessel myocardial infarction and definite or probable scaffold thrombosis were absent.

CONCLUSIONS

Data at the end of the resorption period of DREAMS 3G showed that the third-generation bioresorbable magnesium scaffold is clinically safe and effective, making it a possible alternative to DES.

CLINICALTRIALS

gov: NCT04157153.

Angiography-Based Superficial Wall Strain of De Novo Stenotic Coronary Arteries: Serial Assessment of Vessels Treated with Bioresorbable Scaffold or Drug-Eluting Stent

OBJECTIVES

This study sought to present an angiography-based computational model for serial assessment of superficial wall strain (SWS, dimensionless) of de-novo coronary stenoses treated with either bioresorbable scaffold (BRS) or drug-eluting stent (DES).

BACKGROUND

A novel method for SWS allows the assessment of the mechanical status of arteries in-vivo, which may help for predicting cardiovascular outcomes.

METHODS

Patients with arterial stenosis treated with BRS (n = 21) or DES (n = 21) were included from ABSORB Cohort B1 and AIDA trials. The SWS analyses were performed along with quantitative coronary angiography (QCA) at pre-PCI, post-PCI, and 5-year follow-up. Measurements of QCA and SWS parameters were quantified at the treated segment and adjacent 5-mm proximal and distal edges.

RESULTS

Before PCI, the peak SWS on the 'to be treated' segment (0.79 ± 0.36) was significantly higher than at both virtual edges (0.44 ± 0.14 and 0.45 ± 0.21; both p < 0.001). The peak SWS in the treated segment significantly decreased by 0.44 ± 0.13 (p < 0.001). The surface area of high SWS decreased from 69.97mm2 to 40.08mm2 (p = 0.002). The peak SWS in BRS group decreased to a similar extent (p = 0.775) from 0.81 ± 0.36 to 0.41 ± 0.14 (p < 0.001), compared with DES group from 0.77 ± 0.39 to 0.47 ± 0.13 (p = 0.001). Relocation of high SWS to device edges was often observed in both groups after PCI (35 of 82 cases, 41.7 %). At follow-up of BRS, the peak SWS remained unchanged compared to post-PCI (0.40 ± 0.12 versus 0.36 ± 0.09, p = 0.319).

CONCLUSION

Angiography-based SWS provided valuable information about the mechanical status of coronary arteries. Device implantation led to a significant decrease of SWS to a similar extent with either polymer-based scaffolds or permanent metallic stents.

Challenges and chances coexist: A visualized analysis and bibliometric study of research on bioresorbable vascular scaffolds from 2000 to 2022

BACKGROUND

Bioresorbable scaffolds (BVS) provide a transient supporting force for blocked vessels and allow them to return to previous physiological characteristics. After verification with twists and turns, it has been acknowledged as an emerging revolution in percutaneous coronary intervention that expresses the current concept of intervention without placement. Through this bibliometric study, we organized the knowledge structure of bioresorbable scaffolds and attempted to predict future research hotspots in this field.

METHODS

seven thousand sixty-three articles were retrieved from the web of science core collection database from 2000 to 2022. Then, we utilize CiteSpace 6.1.R2, Biblioshiny and VOS viewer 1.6.18 to analyze the data visually.

RESULTS

First, according to the spatial analysis, the number of annual publications has shown an approximately increasing trend over the past 2 decades. The USA, the People's Republic of China, and GERMANY published the most articles on bioresorbable scaffolds. Second, SERRUYS P ranked first for his most prolific work and highest cited frequency in this domain. Third, the hotspots in this field can be inferred from the keyword distribution; they were the fabrication technique based on tissue engineering; the factors to be optimized for bioresorbable scaffolds, such as mechanical property, degradation, and implantation; and the common adverse effects of bioresorbable scaffolds, such as thrombosis. Most importantly, in terms of burst detection, we could speculate that cutting-edge technology for manufacturing scaffolds represented by 3D printing constitutes the future hotspots in bioresorbable scaffold development.

CONCLUSION

In the first visualized bibliometric analysis of BVS, we attempt to provide a panoramic view. By enrolling extensive literature, we review the growing trend of BVSs. Since its first introduction, it has been through periods of early prosperity, questioned safety subsequently and the resultantly advanced techniques in recent years. In future, the research should focus on utilizing novel techniques to consummate the manufacturing quality and assure the safety of BVSs.

Challenges of the newer generation of resorbable magnesium scaffolds: Lessons from failure mechanisms of the past generation

Bioresorbable scaffolds (BRS) were developed to overcome the obstacles of metallic stents, mostly related to sustained presence of metallic foreign body in the coronary vessel. Following earlier success of single-arm BRS studies, randomized controlled trials of Absorb bioresorbable vascular scaffold (Abbott Vascular, Santa Clara, CA, USA) showed poor long-term clinical outcomes, particularly in terms of scaffold thrombosis. BRS made from magnesium alloy provide a promising alternative in terms of radial force, strut thickness and, potentially lower thrombogenicity. A recent clinical study demonstrated that magnesium-based BRS seems to be promising with regards to the risk of scaffold thrombosis. In this review, our aim is to describe the issues that prevented Absorb BVS from achieving favorable outcomes, provide current status of existing BRS technologies and the challenges that newer generation BRSs need to overcome, and the results of clinical studies for commercially available magnesium-based BRS, which remain the only BRS actively studied in clinical practice.

The bioresorbable magnesium scaffold (Magmaris)-State of the art: From basic concept to clinical application

Since its introduction to clinical practice, coronary artery stent implantation has become a crucial part of the therapy of coronary artery disease (CAD). Despite the undeniable evolution of percutaneous coronary revascularization procedures, drug-eluting stent (DES) technology shows some limitations. To overcome these limitations bioresorbable vascular scaffolds (BRS) were designed as a vessel-supporting technology allowing for anatomical and functional restoration of the vessel after the scaffold intended resorption. Various materials have been proposed as the basis of the scaffold backbone. In this narrative review, we present second-generation magnesium-alloy bioresorbable scaffold devices (Magmaris; Biotronik). Additionally, we discuss available preclinical and clinical data regarding this new magnesium BRS.

Five-year comparative study of thin-strut rapamycin-eluting bioabsorbable scaffold with metallic drug-eluting stent in porcine coronary artery

Objectives

Using quantitative coronary angiography (QCA), optical coherence tomography (OCT), histomorphometry, and pharmacokinetics, this study tried to evaluate the safety and efficacy of Biomagic rapamycin-eluting bioabsorbable scaffold (BVS) in non-atherosclerotic porcine coronary arteries.

Background

Biomagic BVS is a new generation of thin-strut bioabsorbable scaffold. We conducted comparative study detailing pathological response, safety and efficacy of Biomagic BVS and the Firebird2 rapamycin-eluting cobalt-based alloy stent (DES) in a porcine coronary artery model. The animals were followed up at 14 days, 1, 3, 6, 12, 18, 24, 30, 36, 42, 48, 54, and 60 months after stent implantation.

Methods

A total of 143 devices (95 Biomagic and 48 Firebird2) were implanted in 2 or 3 main coronary arteries of 76 nonatherosclerotic swine and examined by QCA, OCT, light microscopy, and pharmacokinetics analyses at various time points.

Results

Vascular responses to Biomagic and Firebird2 were largely comparable at all time points, with struts being sequestered within the neointima. The degree of inflammation of both devices was mild to moderate, although the Biomagic score was higher at 14 days to 24 months. However, there was no statistical difference between the two groups except 14 days. At each follow-up time point, the percentage of area stenosis in the Biomagic group was greater than that in the Firebird 2 group, but there was no statistical difference between the two groups at 3 and 12 months. The extent of fibrin deposition was similar between Biomagic and Firebird2, which peaked at 1 month and decreased rapidly thereafter. Pharmacokinetic study showed that coronary tissue sirolimus concentration remained above 2 ng/mg of tissue at 28 day. Histomorphometry showed expansile remodeling of Biomagic-implanted arteries starting after 12 months, and lumen area was significantly greater in Biomagic than Firebird2 at 36 and 42 months. These changes correlated with dismantling of Biomagic seen after 12 months. OCT images confirmed that degradation of Biomagic was complete by 36 months.

Conclusions

Biomagic demonstrates comparable long-term safety to Firebird2 in porcine coronary arteries with mild to moderate inflammation. Although Biomagic was associated with greater percent stenosis relative to Firebird2 within 36 months, expansile remodeling was observed after 12 months in Biomagic with significantly greater lumen area at ≥36 months. Scaffold resorption is considered complete at 36 months.

Long-Term Performance of the Magmaris Drug-Eluting Bioresorbable Metallic Scaffold in All-Comers Patients’ Population

Background: The long-term efficacy and safety of bioresorbable vascular scaffolds (BVS) in real world clinical practice including Magmaris need to be elucidated to better understand performance of this new and evolutive technology. The aim of this study was to evaluate long-term performance of Magmaris, drug-eluting bioresorbable metallic scaffold, in all-comers patients’ population. Methods: We included in this prospective registry first 54 patients (54 ± 11 years; male 46) treated with Magmaris, with at least 30 months of follow-up. Diabetes mellitus and acute coronary syndrome were present in 33 (61%) and 30 (56%) of the patients, respectively. Patients were followed for device- and patient-oriented cardiac events during a median follow-up of 47 months (DOCE–cardiac death, target vessel myocardial infarction, and target lesion revascularization; POCE–all cause death, any myocardial infarction, any revascularization). Results: Event-free survivals for DOCE and POCE were 86.8% and 79.2%, respectively. The rate of DOCE was 7/54 (13%), including in total target vessel myocardial infarction in two patients (4%), target lesion revascularization in six patients (11%), and no cardiac deaths. The rate of POCE was 11/54 (21%), including in total any myocardial infarctions in 3 patients (6%), any revascularization in 11 patients (20%), and no deaths. Definite Magmaris thrombosis occurred in two patients (3.7%), and in-scaffold restenosis developed in five patients (9.3%). Variables associated with DOCE were implantation of ≥2 Magmaris BVS (HR: 5.4; 95%CI: 1.21–24.456; p = 0.027) and total length of Magmaris BVS ≥ 40 mm (HR: 6.4; 95%CI: 1.419–28.855; p = 0.016), whereas previous PCI was the only independent predictor of POCE (HR: 7.4; 95%CI: 2.216–24.613; p = 0.001). Conclusions: The results of the long-term clinical outcome following Magmaris implantation in patients with complex clinical and angiographic features were acceptable and promising. Patients with multi-BVS and longer multi-BVS in lesion implantation were associated with worse clinical outcome.

Outcomes of the two generations of bioresorbable scaffolds (Magmaris vs. Absorb) in acute coronary syndrome in routine clinical practice

BACKGROUND

Acute coronary syndrome (ACS) as a clinical manifestation of coronary artery disease (CAD) remains a significant cause of mortality and morbidity, as reported worldwide annually. The second generation of drug-eluting stents (DES) is a gold standard in percutaneous interventions in ACS patients however, permanent caging of the vessel with metallic DES has some drawbacks. Bioresorbable vascular scaffolds (BRS) were designed as a temporal vessel-supporting technology allowing for anatomical and functional restoration. Nevertheless, following the initial encouraging reports, numerous concerns about the safety of BRS occurred.

METHODS

In this study, a 1-year performance of 193 patients with magnesium BRS - Magmaris (Biotronik, Berlin, Germany) was evaluated in comparison to 160 patients with polymer BRS - Absorb (Abbott-Vascular, Chicago, USA) in the non-ST-segment elevation-ACS setting.

RESULTS

The Magmaris, when compared to Absorb showed a significantly lower rate of primary endpoint (death from cardiac causes, myocardial infarction, stent thrombosis) as well as target lesion failure in 30-day and 1 year follow-up. In the Absorb group, a significantly higher rate of stent thrombosis was observed.

CONCLUSIONS

Data from the present study suggests encouraging safety a profile and more favorable clinical outcomes of Magnesium BRS in comparison to the polymer Absorb - BRS.

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 ≧ 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).

CONCLUSIONS

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.

Long-term vascular function in CTO recanalization: A randomized clinical trial of ticagrelor vs. clopidogrel

BACKGROUND

Coronary vascular function of a chronic coronary total occlusion (CTO) immediately after recanalization is known to be poor and to be partially improved by pre-treatment with loading dose of ticagrelor vs. clopidogrel. It is unknown if this vascular dysfunction is maintained at long-term follow-up and may be improved by 1-year dual antiplatelet therapy (DAPT).

METHODS

The TIGER is a prospective, open-label, two parallel-group controlled clinical trial, which 1:1 randomized 50 CTO patients to pre-PCI loading dose and subsequent 1-year DAPT with ticagrelor vs. clopidogrel. Coronary blood flow (CBF) under stepwise adenosine infusion was assessed after drug loading dose and at follow-up and compared between the two drug groups, adjusting for time of follow-up.

RESULTS

Out of 50 patients with index CBF evaluation, 38 (76%) patients underwent angiographic follow-up (23 and 15 at 1 and 3-year, respectively) and Doppler data was available in 35 (70%). A high CBF area under the curve (AUC), already observed after loading dose in ticagrelor vs. clopidogrel group (p = 0.027), was maintained at follow-up (AUC 34815.22 ± 24,206.06 vs. AUC 22712.47 ± 13,768.95; p = 0.071). Specifically, whereas high ticagrelor loading dose-related CBF was sustained at follow-up (p = 0.933), clopidogrel loading dose-related CBF increased at follow-up (p = 0.039).

CONCLUSION

The TIGER trial showed that DAPT with ticagrelor maintained a non-significantly higher CBF in a recanalized CTO as compared to clopidogrel, whose treated patients exhibit a lower CBF immediately after PCI with a significant increase at follow-up. The clinical value of such sustained high coronary flow should be evaluated in a larger group of patients.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT02211066 (ClinicalTrials.gov number NCT02211066).

Critical evaluation of stents in coronary angioplasty: a systematic review

BACKGROUND

Coronary stents are routinely placed in the treatment and prophylaxis of coronary artery disease (CAD). Current coronary stent designs are prone to developing blockages: in-stent thrombosis (IST) and in-stent re-stenosis (ISR). This is a systematic review of the design of current coronary stent models, their structural properties and their modes of application, with a focus on their associated risks of IST and ISR. The primary aim of this review is to identify the best stent design features for reducing the risk of IST and ISR. To review the three major types of stents used in clinical settings today, determining best and relevant clinical practice by exploring which types and features of offer improved patient outcomes regarding coronary angioplasty. This information can potentially be used to increase the success rate of coronary angioplasty and stent technology in the future taking into account costs and benefits.

METHODS

Scientific databases were searched to find studies concerning stents. After the exclusion criteria were applied, 19 of the 3192 searched literature were included in this review. Studies investigating three major types of stent design were found: bare-metal stents (BMS), drug-eluting stents (DES) and bioresorbable stents (BRS). The number of participants varied between 14 and 1264. On average 77.4% were male, with a mean age of 64 years.

RESULTS

From the findings of these studies, it is clear that DES are superior in reducing the risk of ISR when compared to BMS. Conflicting results do not clarify whether BRS are superior to DES at reducing IST occurrence, although studies into newer BRS technologies show reducing events of IST to 0, creating a promising future for BRS showing them to be non-inferior. Thinner stents were shown to reduce IST rates, due to better re-endothelialisation. Scaffold material has also been shown to play a role with cobalt alloy stents reducing the risk of IST. This study found that thinner stents that release drugs were better at preventing re-blockages. Some dissolvable stents might be better at stopping blood clots blocking the arteries when compared to metal stents. The method and procedure of implanting the stent during coronary angioplasty influences success rate of these stents, meaning stent design is not the only significant factor to consider.

CONCLUSIONS

Positive developments in coronary angioplasty could be made by designing new stents that encompass all the most desirable properties of existing stent technology. Further work is needed to investigate the benefits of BRS in reducing the risk of IST compared to DES, as well as to investigate the effects of different scaffold materials on IST and ISR outcomes.

Bioresorbable Stent to Manage Congenital Heart Defects in Children

Intravascular stents for pediatric patients that degrade without inhibiting vessel growth remain a clinical challenge. Here, poly(L-lactide) fibers (DH-BDS) at two thicknesses, 250 μm and 300 μm, were assembled into large, pediatric-sized stents (Ø10 - Ø20 mm). Fibers were characterized mechanically and thermally, then stent mechanical properties were compared to metal controls, while mass loss and degradation kinetics modeling estimated total stent degradation time. Thicker fibers displayed lower stiffness (1969 ± 44 vs 2126 ± 37 MPa) and yield stress (117 ± 12 vs 137 ± 5 MPa) than thinner counterparts, but exhibited similar fail strength (478 ± 28 vs 476 ± 16 MPa) at higher strains (47 ± 2 vs 44 ± 2%). Stents all exhibited crystallinity between 51.3 - 54.4% and fiber glass transition temperatures of 88.6 ± 0.5 °C and 84.6 ± 0.5 °C were well above physiological ranges. Radial strength (0.31 ± 0.01 - 0.34 ± 0.02 N/mm) in thinner stents was similar to metal stents (0.24 - 0.41 N/mm) up to Ø14 mm with no foreshortening and thicker coils granted comparable radial strength (0.32 ± 0.02 - 0.34 ± 0.02 N/mm) in stents larger than Ø14 mm. Both 10 mm (1.17 ± 0.02 % and 0.86 ± 0.1 %) and 12 mm (1.1 ± 0.03% and 0.89 ± 0.1%) stents exhibited minimal weight loss over one year. Degradation kinetics models predicted full stent degradation within 2.8 - 4.5 years depending on thickness. DH-BDS exhibiting hoop strength similar to metal stents and demonstrating minimal degradation and strength loss over the first year before completely disappearing within 3 to 4.5 years show promise as a pediatric interventional alternative to current strategies.

Current perspectives on bioresorbable scaffolds in coronary intervention and other fields

Introduction: The first-generation bioresorbable scaffolds (BRSs) had a large strut profile to compensate for the insufficient radial strength of bioresorbable polymer materials, resulting in higher scaffold thrombosis rates than conventional drug-eluting stents. To improve the clinical safety and efficacy, the new generation BRSs have been improved by optimal structure design, post-processing of bioresorbable polymer materials, or altering bioresorbable metallic alloys.Areas covered: This review summarizes the lessons learned from the first-generation BRS, updates the clinical outcomes of trials evaluating ABSORB bioresorbable vascular scaffold at long-term and bioresorbable metallic alloy-based devices, and examines recent outcomes of BRS treated in STEMI patients. This review also provides an overview of the current clinical data of seven BRSs manufactured in Asia, and of the BRSs extended application in other clinical arenas.Expert opinion: Drawbacks of the first-generation BRSs need to be addressed by the next generation of these stents with novel materials and technologies. Clinical research, including randomized controlled trials, are required to further evaluate BRSs application in coronary artery disease. The encouraging results of BRSs innovation applied in the peripheral arteries and gastrointestinal tracts support other potential clinical applications of BRS technology.

Successful bailout stenting strategy against rare spontaneous retrograde dissection of partially absorbed magnesium-based resorbable scaffold: A case report

BACKGROUND

In the development of coronary stent technology, bioresorbable scaffolds are promising milestones in improving the clinical treatment of coronary artery disease. The “leave nothing behind” motto is the premise of the fourth revolution in percutaneous coronary intervention (PCI). Studies proving the safety and efficacy of the magnesium-based resorbable scaffolds (MgBRSs) include the BIOSOLVE-I and BIOSOLVE-II trials and the latest BIOSOLVE-IV registry. However, spontaneous retrograde dissection of a partially absorbed MgBRS may still occur, albeit rarely.

CASE SUMMARY

We describe an unusual case of coronary artery disease in a patient who had undergone a successful PCI 8 mo earlier, where an MgBRS was implanted into the left anterior descending artery (LAD) and left circumflex artery with drug-coated balloons for a ramus intermedius branch stenosis to achieve the “leave nothing behind” therapeutic intention and was currently presenting with a gradual worsening of chest tightness. The distal edge vascular response, during subsequent attempts with balloon angioplasty was performed smoothly. However, spontaneous retrograde dissection of a partially absorbed MgBRS in the LAD ensued. Successful bailout stenting was performed with revascularization of the entry and exit sites created by spontaneous dissection and complete sealing of the intramural hematoma. The patient recovered well and was discharged after 2 d of intervention. When followed up in August 2020 (7 mo later), the patient showed uneventful recovery.

CONCLUSION

Spontaneous retrograde dissection of a partially absorbed MgBRS was successfully treated using bailout sirolimus-eluting coronary stent strategy.

The role of optical coherence tomography guidance in scaffold versus stent optimization

BACKGROUND

Optical coherence tomography showed a great ability to identify adverse features during percutaneous coronary intervention with drug-eluting stents and resulted in better clinical outcomes. The study aimed to assess the impact of optical coherence tomography on intraoperative decision-making during implantation of Absorb bioresorbable scaffolds versus everolimus drug-eluting stents.

RESULTS

We performed an observational study that included 223 consecutive patients post optical coherence tomography-guided implantation of either Absorb bioresorbable scaffolds (162 patients) or everolimus drug-eluting stents (61 patients). We studied the influence of optical coherence tomography on intraoperative decision-making during implantation of bioresorbable scaffolds versus drug-eluting stents by analyzing the total rate of optical coherence tomography-dependent modifications in each device. After satisfactory angiographic results, the total rate of required intervention for optical coherence tomography detected complications was significantly higher in the bioresorbable scaffolds arm compared to drug-eluting stents arm (47.8% versus 32.9%, respectively; p = 0.019). The additional modifications encompassed further optimization in the case of device underexpansion or struts malapposition, and even stenting in the case of strut fractures, or significant edge dissection.

CONCLUSIONS

Compared to drug-eluting stents, Absord scaffold was associated with a significantly higher rate of optical coherence tomography-identified intraprocedural complications necessitating further modifications. The study provides some hints on the reasons of scaffolds failure in current PCI practice; it offers a new insight for the enhancement of BRS safety and presents and adds to the growing literature for successful BRS utilization.

A systematic review and meta-analysis of bioresorbable vascular scaffolds for below-the-knee arterial disease

INTRODUCTION

Different types of bioresorbable vascular scaffolds (BVSs) have been developed and used in below-the-knee (BTK) arterial diseases. This is the first study reviewing and analyzing the literature on BVS treatment for BTK arterial disease.

EVIDENCE ACQUISITION

MEDLINE, Embase, and Cochrane were searched for studies published until October 21, 2019. The search, study selection, quality assessment, and data extraction were performed by 2 authors independently. Articles that studied the treatment of BTK arterial disease by using BVSs were eligible. Exclusion criteria were studies with a variant design (e.g. case reports <5 patients), non-BTK indications for BVS use, and nonhuman studies. Primary endpoint was 12-month primary patency. Secondary endpoints were 12-month freedom from clinically driven target lesion revascularization (CD-TLR), limb salvage, survival, and amputation-free survival (AFS). Study quality was assessed by the Methodological Index for Non-randomized Studies score.

EVIDENCE SYNTHESIS

Five studies representing 155 patients with 160 treated limbs met the inclusion criteria. Pooled 12-month primary patency per limb was 90% (143/160; 95% confidence interval [CI]: 0.84-0.95), freedom from CD-TLR 96% (124/130; 95% CI: 0.91-0.99), limb salvage rate 97% (156/160; 95% CI: 0.94-1.00), survival rate 90% (112/125; 95% CI: 0.82-0.96), and AFS rate 89% (110/125; 95% CI: 0.81-0.94). Subgroup analyses of included Absorb BVS studies showed similar results. All studies were assessed as moderate quality.

CONCLUSIONS

This meta-analysis of case series showed good 12-month patency and clinical results with BVSs for BTK arterial disease, even in patients with multimorbidity and short but complex lesions. These results encourage a revival of this scaffold.

First in human evaluation of a novel Sirolimus-eluting ultra-high molecular weight bioresorbable scaffold: 9-, 24-and 36-months imaging and clinical results from the multi-center RENASCENT study

BACKGROUND

RENASCENT is a prospective, multi-center first-in-human clinical study to evaluate the clinical performance of the novel sirolimus-eluting 150-μm strut thickness FORTITUDE® BRS for percutaneous coronary intervention of single de novo coronary lesions.

METHODS

FORTITUDE® BRS was tested in a prospective study in Italy and Colombia. Study objectives were in-scaffold angiographic late lumen loss (LLL) measured by quantitative coronary angiography and target vessel failure (TVF) defined as the composite rate of cardiac death, target vessel myocardial infarction or ischemia driven target lesion revascularization (TLR) at 9- and 24-months with clinical results up to 36-months.

RESULTS

A total of 63 patients were enrolled. All patients underwent lesion pre-dilatation and 22 patients (34.9%) underwent post-dilatation. Clinical device and procedural success was 98.4% (62/63 patients) and 96.8% (61/63 patients) respectively. At 9-months, TVF occurred in 3/61 (4.9%) of the patients including 2 peri-procedural MI and one ischemia-driven TLR. Between 9- to 24-months, ischemia-driven TLR occurred in 3 additional patients (4.9%) including 1 patient who presented with very late ST after stopping all medications. There were no further TVF between 24- and 36-months.

CONCLUSIONS

In this multi-center prospective study, the FORTITUDE® BRS was shown to be safe and effective in the treatment of single coronary lesions with low levels of TVF and LLL at 9- and 24-months. It was shown to be clinically safe upto 36-months follow-up.

Visibility of Bioresorbable Vascular Scaffold in Intravascular Ultrasound Imaging

Bioresorbable vascular scaffold (BVS) has recently been spotlighted for its unique characteristics of absorbing into blood vessels and eventually disappearing. Although intravascular ultrasound (IVUS) is the most common guiding tool for stent deployment, the echogenicity of BVS struts has changed as the center of stent lumen and scanning rotation is not concentric, which may cause a critical erroneous measurement in practice. This study investigated the physical conditions for dimming the stent brightness in IVUS images using a finite-difference method (FDM) to numerically solve acoustic wave propagation through nonhomogeneous medium. The dimmed brightness is caused by an angled rectangular cross section of a strut and its similar acoustic impedance with water. Imaging frequency is not a major cause. However, the angle between the acoustic beam and the BVS surface is the major cause of the dimmed brightness. As a solution, an approach using a frequency compounding method with signal polarity comparator was proposed to recover the reduced brightness without sacrificing spatial resolutions. Based on the simulation study, the signal level from BVS can be attenuated down by 17 dB when the angle between the acoustic beamline and the surface of BVS is more than 45°. With the proposed frequency compounding approach, the reduced signal can be recovered by 6 dB. In the experimental BVS IVUS imaging, strut brightness was reduced by 18 dB with an angled strut position and recovered by 5 dB with the proposed frequency compounding method. A pig coronary was imaged to demonstrate the performance of the proposed method.

A case report of a recurrent early and late Bioresorbable vascular scaffold thrombosis: serial angiography and optical coherence tomography findings

Background

In bioresorbable vascular scaffolds (BVSs), there is some concern about a possible increase in the rate of scaffold thromboses (ScTs). Although several characteristics similarly contribute to the development of both early and late ScTs, there are also clearly different pathomechanisms between the two time-dependent types of thromboses, especially with BVSs.

Case presentation

We recently experienced a very rare case of a 69-year-old man who had recurrent early and late ScTs with somewhat differing pathomechanisms as assessed by optical coherence tomography (OCT). For the late ScT, OCT identified a scaffold dismantling in the same place that a peri-strut low intensity area (PLIA) was observed in the previous OCT finding.

Conclusion

We report the management of an ScT in a case with findings such as a heterogeneous a BVS degradation, peri-strut low intensity area (PLIA), intraluminal scaffold dismantling, and under-sizing and/or stent malapposition observed in OCT.

Five Years Outcomes and Predictors of Events in a Single-Center Cohort of Patients Treated with Bioresorbable Coronary Vascular Scaffolds

Introduction: We report outcome data of patients treated with coronary bioresorbable scaffolds up to 5 years and investigate predictors of adverse events. Methods: Consecutive patients treated with at least one coronary bioresorbable scaffold (BRS, Abbott Vascular, Santa Clara, USA) between May 2012 and May 2014 in our center were enrolled. Clinical/procedural characteristics and outcome data at 1868 (1641–2024) days were collected. The incidence of scaffold thrombosis (ScT), restenosis (ScR), and target lesion failure (TLF) and their predictors were investigated using Kaplan–Meier and Cox regression analysis. Results: 512 consecutive patients and 598 lesions were included in the database. A total of 30 ScT, 42 ScR, and 92 TLF were reported. The rate of ScT was 3.6% in the first year, 2.2% in the second–third year, and 0.6% in the fourth–fifth year after implantation. The corresponding rates of ScR were 2.5%, 5.7%, and 1.1%. The corresponding incidence of TLF was 8.8%, 8.0%, 3.8%. Procedural parameters (vessel size, scaffold footprint) and the technique used at implantation (including predilation, parameters of sizing, and postdilation) were predictors of ScT and TLF in the first three years after implantation. In contrast, only diabetes was predictive of events between 4–5 years (HR 6.21(1.99–19.40), p = 0.002). Conclusions: After device resorption, the incidence of very late adverse events in lesions/patients implanted with a BRS decreases. Procedural and device-related parameters are not predictors of events anymore.

Mechanism of Drug-Eluting Absorbable Metal Scaffold Restenosis

Background:

The pathomechanisms underlying restenosis of the bioabsorbable sirolimus-eluting metallic scaffold (Magmaris) remain unknown. Using serial optical coherence tomography, we investigated causes of restenosis, including the contribution of late scaffold recoil versus neointimal hyperplasia.

Methods:

Patients enrolled in BIOSOLVE-II undergoing serial angiography and optical coherence tomography (post-intervention and follow-up: 6 months and/or 1 year) were analyzed. Patients were divided into 2 groups according to angiographic in-scaffold late lumen loss (LLL) <0.5 or ≥0.5 mm. End points were late absolute scaffold recoil and neointimal hyperplasia area as assessed by optical coherence tomography.

Results:

Serial data were available for analysis from 70 patients (LLL <0.5 mm: n=41; LLL ≥0.5 mm: n=29). Patient and lesion characteristics were comparable, and there was no significant difference in mean and minimal scaffold area between groups at post-intervention. Late absolute scaffold recoil was less among patients with LLL <0.5 mm (0.53±0.68 mm 2 ) compared with those with LLL ≥0.5 mm (1.48±1.20 mm 2 ; P <0.001). Neointimal hyperplasia area was smaller among patients with LLL <0.5 mm at follow-up (1.47±0.33 mm 2 ) compared with patients with LLL ≥0.5 mm (1.68±0.34 mm 2 ; P =0.013). In a matched-frame analysis (post-intervention and follow-up), late absolute scaffold recoil varied according to the underlying plaque type (lipid: 0.63±1.23 mm 2 ; calcified: 0.81±1.44 mm 2 ; and fibrous: 1.20±1.52 mm 2 ; P <0.001), while there was no difference with regards to neointimal hyperplasia area ( P =0.132).

Conclusions:

In addition to neointimal hyperplasia, late scaffold recoil contributed significantly to LLL of sirolimus-eluting absorbable metal scaffolds. The extent of late scaffold recoil was dependent on the underlying plaque morphology and was the highest among fibrotic lesions.

Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01960504.

Intracoronary Imaging for Assessment of Vascular Healing and Stent Follow-up in Bioresorbable Vascular Scaffolds

Bioresorbable Vascular Scaffolds (BVS) are polymer-based materials implanted in the coronary arteries in order to treat atherosclerotic lesions, based on the concept that once the lesion has been treated, the material of the implanted stent will undergo a process of gradual resorption that will leave, in several years, the vessel wall smooth, free of any foreign material and with its vasomotion restored. However, after the first enthusiastic reports on the efficacy of BVSs, the recently published trials demonstrated disappointing results regarding long-term patency following BVS implantation, which were mainly attributed to technical deficiencies during the stenting procedure. Intracoronary imaging could play a crucial role for helping the operator to correctly implant a BVS into the coronary artery, as well as providing relevant information in the follow-up period. This review aims to summarize the role of intracoronary imaging in the follow-up of coronary stents, with a particular emphasis on the role of intravascular ultrasound and optical coherence tomography for procedural guidance during stent implantation and also for follow-up of bioabsorbable scaffolds.

Fully bioresorbable vascular scaffolds: lessons learned and future directions

Fully bioresorbable scaffolds (BRS) were designed to overcome the limitations of metallic drug-eluting stents, which permanently cage the vessel wall, thereby preventing normal coronary vasomotion, preclude bypass grafting and can provoke long-term foreign-body responses. Although multiple scaffolds have been or are in development, the Absorb Bioresorbable Vascular Scaffold (BVS; Abbott Vascular) was the first FDA-approved device and was widely expected to fulfil the dream of interventional cardiologists of a transient scaffold that would disappear 'when the job was done' and would not hamper further treatment options. Although early, small studies and even large, randomized trials showed beneficial outcomes up to 1 year of follow-up, longer-term results have been disappointing, with increased rates of device thrombosis and target-lesion revascularization. The Absorb BVS device was withdrawn from the market because of low demand. In this Review, we summarize the preclinical and clinical data available for BRS to understand how the vascular biological reactions to these devices differ from biological reactions to metallic drug-eluting stents and how these responses translate into clinical outcomes. We also discuss next-generation BRS and outline modifications that are needed to improve the long-term outcomes with these devices so that they eventually become a viable option for patients with symptomatic obstructive coronary artery disease.

Absorb GT1 Bioresorbable Vascular Scaffold System - 1-Year Post-Marketing Surveillance in Japan

BACKGROUND

The Japan post-marketing surveillance (PMS) for the Absorb GT1 bioresorbable vascular scaffold (BVS) mandated an intracoronary imaging-guided implantation technique.Methods and Results:We enrolled 135 patients who were planned to undergo PCI with THE Absorb GT1. Adequate lesion preparation, imaging-guided appropriate sizing, and high-pressure post-dilatation using a noncompliant balloon to minimize final diameter stenosis were recommended. The primary endpoint was the scaffold thrombosis rate at 3 months. All patients successfully received at least 1 Absorb GT1 at the index procedure and completed 1-year follow-up. All 139 lesions were predilatated: cutting/scoring balloon and noncompliant balloon were used in 48 (34.5%) and 58 (41.7%) lesions, respectively. Post-dilatation was performed in 137 (98.5%) lesions with mean high pressure of 18.8 atm. Optical coherence tomography (OCT) was used in 127 of 139 (91.4%) lesions, and revealed 56.7% of lesions had incomplete scaffold apposition (ISA) but only in 1.89% in the per strut analysis. All patients received adenosine diphosphate receptor antagonist at discharge, and 132 (97.8%) patients continued therapy through the year. No definite/probable scaffold thrombosis, cardiac death, myocardial infarction, or ischemia-driven target lesion revascularization was reported up to 1 year follow-up.

CONCLUSIONS

Appropriate OCT-guided BVS implantation may prevent incomplete strut apposition, thereby reducing the risk of target lesion failure and scaffold thrombosis.

Neoatherosclerosis - Long-Term Assessment of Bioresorbable Vascular Scaffold

Although metallic stents improved the safety and efficacy of percutaneous coronary intervention (PCI), even the latest generation of drug-eluting stents (DES) is still limited by several factors. The limitations of DES are mainly related to the permanent metallic caging in vessel, chronic inflammatory response to the polymer and adverse effects of antiproliferative drug on endothelial tissue, leading to impaired physiological vasomotor response and late stent-related adverse events such as stent thrombosis and neoatherosclerosis. Bioresorbable vascular scaffold (Absorb BVS; Abbott Vascular) was designed to overcome these drawbacks of DES by disappearing from the vessel wall. Absorb BVS, however, was withdrawn from the world market because of increased incidence of scaffold thrombosis compared with DES. Importantly, only very limited long-term post-BVS implantation data are available, especially with regard to neoatherosclerosis, which can lead to very late adverse events even after resorption of the scaffold. Therefore, the goal of this review was to highlight the mid to long term clinical outcomes published to date, and to describe the features of the intimal healing process and neoatherosclerosis in the 5 years following Absorb BVS implantation, mainly based on our previous study. This may provide important information on the pathophysiology of the scaffolded vessel for clinicians, and promote identification of future bioresorbable materials for PCI that will minimize the stimulus for neoatherosclerosis.

The 1‑year safety and efficacy outcomes of Absorb bioresorbable vascular scaffolds for coronary artery disease treatment in diabetes mellitus patients: the ABSORB DM Benelux study

BACKGROUND

Diabetes mellitus (DM) patients show higher rates of repeat revascularisation even in the era of modern drug-eluting stents (DES). The concept of bioresorbable scaffolds is becoming captivating, as it might allow for repeat interventions, prolonging the time span during which patients can be treated by percutaneous coronary intervention (PCI).

AIMS

We intend to evaluate the short- and long-term safety and efficacy of Absorb bioresorbable vascular scaffolds (Absorb BVS) in the treatment of coronary artery disease (CAD) in DM patients for any indication.

METHODS

The ABSORB DM Benelux is an international prospective study in DM patients who have undergone PCI with ≥1 Absorb BVS. Major adverse cardiac events (MACE) at 1 year was the primary endpoint, defined as a composite of all-cause death, any myocardial infarction (MI) and ischaemia-driven target vessel revascularisation (TVR). Secondary endpoints were target lesion failure (TLF) and definite or probable scaffold thrombosis (ScT).

RESULTS

Between April 2015 and March 2017, 150 DM patients and 188 non-complex lesions were treated. Device implantation was successful in 100%. MACE occurred in 14 (9.5%) patients, with all-cause death occurring in 4 (2.7%), any MI in 6 (4.1%) and ischaemia-driven TVR in 7 (4.8%) respectively. TLF was reported in 11 (7.5%). Definite and probable ScT was observed in 2 (1.4%).

CONCLUSION

Absorb BVS for treatment of anatomically low-risk patients with DM show acceptable safety and efficacy outcomes at 1 year. If these promising results are confirmed after a longer follow-up period, new-generation bioresorbable scaffolds combined with refinement of implantation techniques might open new horizons for CAD treatment in DM patients.

Impact of strut dimensions and vessel caliber on thrombosis risk of bioresorbable scaffolds using hemodynamic metrics

Bioresorbable scaffolds (BRS) promise to be the treatment of choice for stenosed coronary vessels. But higher thrombosis risk found in current clinical studies limits the expectations. Three hemodynamic metrics are introduced to evaluate the thrombosis risk of coronary stents/scaffolds using transient computational fluid dynamics (CFD). The principal phenomena are platelet activation and effective diffusion (platelet shear number, PSN), convective platelet transport (platelet convection number, PCN) and platelet aggregation (platelet aggregation number, PAN) were taken into consideration. In the present study, two different stent designs (thick-strut vs. thin-strut design) positioned in small- and medium-sized vessels (reference vessel diameter, RVD=2.25 mm vs. 2.70 mm) were analyzed. In both vessel models, the thick-strut design induced higher PSN, PCN and PAN values than the thin-strut design (thick-strut vs. thin-strut: PSN=2.92/2.19 and 0.54/0.30; PCN=3.14/1.15 and 2.08/0.43; PAN: 14.76/8.19 and 20.03/10.18 for RVD=2.25 mm and 2.70 mm). PSN and PCN are increased by the reduction of the vessel size (PSN: RVD=2.25 mm vs. 2.70 mm=5.41 and 7.30; PCN: RVD=2.25 mm vs. 2.70 mm=1.51 and 2.67 for thick-strut and thin-strut designs). The results suggest that bulky stents implanted in small caliber vessels may substantially increase the thrombosis risk. Moreover, sensitivity analyses imply that PSN is mostly influenced by vessel size (lesion-related factor), whereas PCN and PAN sensitively respond to strut-thickness (device-related factor).

Early-Stage Vascular Response between Bare Metal Stent and Drug-Free Bioresorbable Vascular Scaffold in the Small-Sized Peripheral Artery: A Preclinical Study in Porcine Femoral Arteries

BACKGROUND

The clinical benefits and outcomes of the interventional treatment of small-sized infrapopliteal arteries using stent implantation remain uncertain. The aim of this study was to compare the safety and efficacy of drug-free bioresorbable vascular scaffold (BVS) with that of bare metal stent (BMS) in endovascular treatment of small-sized peripheral arteries.

METHODS

In this study, drug-free BVS and BMS were used in eight porcine models. We compared the angiographic and histomorphometric findings in the two groups at 4 weeks. In each pig, BVS and BMS of adequate sizes were implanted in the small branch (<3 mm) of the femoral artery. Angiography, intravascular ultrasound (IVUS), and histomorphometric analysis were performed at 4 weeks.

RESULTS

In the 4-week follow-up angiography and IVUS examination, the minimal luminal diameter was smaller and diameter stenosis was more severe in the BVS group. Histomorphometric findings indicated that the lumen area in the BVS group was smaller (0.34 ± 0.28 mm² vs. 1.40 ± 0.52 mm², P < 0.001), whereas the neointimal area (2.70 ± 1.28 mm² vs. 1.76 ± 0.66 mm², P = 0.013), area stenosis (85.18 ± 13.14 % vs. 54.99 ± 16.13 %, P < 0.001), inflammatory score (2.07 ± 0.861 vs. 28 ± 0.39, P = 0.003), and fibrin scores (1.24 ± 0.70 vs. 0.79 ± 0.72, P = 0.043) were significantly higher in the BVS group. The injury score was higher in the BMS group. In histopathologic findings, restenosis was mainly due to recoil and distortion of the scaffold in the BVS group.

CONCLUSIONS

Compared with BMS, drug-free BVS was not feasible for small-sized peripheral arteries based on the angiographic, IVUS, and histomorphometric results primarily due to insufficient mechanical support.

Procedural findings and early healing response after implantation of a self-apposing bioresorbable scaffold in coronary bifurcation lesions

We aimed to evaluate feasibility, early healing and self-correcting properties of the Desolve 150 bioresorbable scaffold (BRS) implanted in bifurcation lesions, using the simple, provisional side branch (SB) stenting technique. BIFSORB pilot was a proof-of-concept study enrolling 10 patients with stable angina pectoris and a bifurcation lesion with SB ≥ 2.5 mm and less than 50% diameter stenosis. Procedure and 1-month outcome was evaluated by optical coherence tomography (OCT) to assess scaffold performance and healing patterns. Nine patients were treated with Desolve 150 BRS and one delivery to the target bifurcation failed. Thrombus formation in the jailed SB ostium was seen in three cases, but was completely resolved at 1-month. OCT confirmed acute self-correcting properties. No clinical events were reported after six months. Scaffold diameter by OCT increased in the proximal main vessel from 3.09 ± 0.16 mm to 3.34 ± 0.18 mm (p = 0.01) and in distal main vessel from 2.82 ± 0.26 mm to 3.02 ± 0.29 mm (p < 0.01) at one-month follow-up. SB ostial diameter stenosis improved from 42 ± 15% to 34 ± 12% (p = 0.01). Malapposition was effectively reduced after 1 month from 4.1 (1.4; 6.1)% to 0.1 (0; 0.6)% (p = 0.002). Treatment of bifurcation lesions using Desolve 150 BRS was feasible except for a delivery failure and unsettling thrombus formation behind jailing SB struts, which was completely resolved at 1-month. Self-correcting and even self-expanding properties were confirmed.

Everolimus-eluting bioresorbable scaffolds for treatment of coronary artery disease in patients with diabetes mellitus: the midterm follow-up of the prospective ABSORB DM Benelux study

Background

Percutaneous coronary intervention (PCI) in patients with diabetes mellitus (DM) remains challenging even with modern drug-eluting stents (DES) due to high rates of repeat revascularization. Everolimus-eluting bioresorbable scaffolds (EE-BRS) might allow for repeat intervention prolonging the time interval of percutaneous treatment options.

Methods

The ABSORB DM Benelux Study is a dedicated prospective, international study to evaluate the midterm safety and efficacy of EE-BRS in DM patients. All DM patients that received ≥ 1 EE-BRS for any indication were enrolled and prospectively followed. Study endpoints were major adverse cardiac events (MACE): a composite of all-cause death, any myocardial infarction (MI) and ischemic-driven target vessel revascularization (TVR); target lesion failure (TLF): a composite of cardiac death (CD), target vessel MI, and ischemic-driven target lesion revascularization (TLR), as well as definite or probable scaffold thrombosis (ScT).

Results

Between April 2015 till March 2017, 150 DM patients and 188 lesions were treated and followed up to 3 years. Device implantation success was 100%. MACE occurred in 15.2% (event rate of 8.8 per 100 PY). TLF was reported in 11.7% (7.0 events per 100 PY). CD, target vessel MI, ischemic-driven TLR occurred in 3.4%, 3.6% and 5.5% respectively, while ScT was observed in 1.4%. There were no occurrences of late or very late ScT.

Conclusion

EE-BRS treatment in DM patients shows comparable midterm safety and efficacy outcomes when historically compared with modern DES. New-generation EE-BRS might offer an attractive alternative to metallic DES in treatment of fast progressing atherosclerosis population as in DM patients.

Trial registration NTR5447. Registered 05 October 2015, retrospectively registered

Early and long-term outcomes of bioresorbable vascular scaffolds in the treatment of patients with coronary artery disease in real-world clinical practice - insights from the ZABRZE-BVS registry

Introduction

Randomized trials have proven the feasibility and safety of the bioresorbable vascular scaffold (BVS) in selected populations of patients. Data concerning the results of BVS in “real-world” registries with an appropriate sample size are limited.

Aim

Assessment of early- and long-term outcomes of patients undergoing bioresorbable scaffold implantation in an all-comers population of the ZABRZE-BVS registry.

Material and methods

The ZABRZE-BVS registry is a prospective registry including consecutive patients treated in the period 2013–2016 with the intention to implant a BVS (ABSORB, Abbott Vascular, Santa Clara, California). The primary endpoint was occurrence of the 12- and 24-month device-oriented composite endpoint (DoCE) defined as cardiac death, target-vessel myocardial infarction (TV-MI) or target lesion revascularization (TLR). The secondary endpoint includes occurrence of patient-oriented composite endpoint (PoCE) at 12 and 24 months, device (lesion basis) and procedural success (patient basis).

Results

A total of 456 patients during 467 procedures received 588 scaffolds in 563 lesions. Of note, 25.4% of patients presented with diabetes mellitus and 62.3% had an acute coronary syndrome. In QCA analysis, 78.7% of patients had type B2/C lesions, minimal lumen diameter was 0.78 ±0.54 mm, whereas post-procedural acute lumen gain was 1.61 ±0.61 mm. Median follow-up was 781 days. The cumulative rate of DoCE was 6.7% at 12 months and 12.2% at 24 months. Rates of 12- and 24-month PoCE were 12.4% and 20.1%, respectively. The percentage of device success was 98.7%, while the procedural success rate was 96.9%.

Conclusions

The Absorb BVS was successfully and safely implanted in an unselected group of patients. Scaffold thrombosis developed predominantly in patients with acute coronary syndrome (ACS).

Exploring the efficacy of natural products in alleviating Alzheimer's disease

Alzheimer’s disease (hereafter AD) is a progressive neurodegenerative disorder that affects the central nervous system. There are multiple factors that cause AD, viz., accumulation of extracellular Amyloid-beta 42 plaques, intracellular hyper-phosphorylated Tau tangles, generation of reactive oxygen species due to mitochondrial dysfunction and genetic mutations. The plaques and tau tangles trigger aberrant signaling, which eventually cause cell death of the neurons. As a result, there is shrinkage of brain, cognitive defects, behavioral and psychological problems. To date, there is no direct cure for AD. Thus, scientists have been testing various strategies like screening for the small inhibitor molecule library or natural products that may block or prevent onset of AD. Historically, natural products have been used in many cultures for the treatment of various diseases. The research on natural products have gained importance as the active compounds extracted from them have medicinal values with reduced side effects, and they are bioavailable. The natural products may target the proteins or members of signaling pathways that get altered in specific diseases. Many natural products are being tested in various animal model systems for their role as a potential therapeutic target for AD, and to address questions about how these natural products can rescue AD or other neurodegenerative disorders. Some of these products are in clinical trials and results are promising because of their neuroprotective, anti-inflammatory, antioxidant, anti-amyloidogenic, anticholinesterase activities and easy availability. This review summarizes the use of animal model systems to identify natural products, which may serve as potential therapeutic targets for AD.

Device specificity of vascular healing following implantation of bioresorbable vascular scaffolds and bioabsorbable polymer metallic drug-eluting stents in human coronary arteries: the ESTROFA OCT BVS vs. BP-DES study

AIMS

We sought to compare vascular healing with bioresorbable everolimus-eluting vascular scaffolds (BVS) and drug-eluting stents with bioabsorbable polymers (BP-DES) at six and 12 months both implanted in the same patients.

METHODS AND RESULTS

This was a multicentre and prospective study including patients with at least two comparable lesions to treat. In every patient both BVS and BP-DES (SYNERGY, Orsiro or BioMatrix Flex) were implanted by lesion randomisation. Patients included were evaluated with optical coherence tomography at six or 12 months (2:1). Finally, 68 patients had an examination at six months and 27 patients at 12 months. The rates of uncovered struts at six months were 1.7±3.2% for BVS and 5.3±5.6% for BP-DES (p=0.0001), and at 12 months 0.48±0.72% and 4.8±5%, respectively (p=0.001). Rates of strut malapposition were significantly lower with BVS. There was no significant intra-patient correlation with BP-DES/BVS for endpoints. Evaginations were more frequent and larger with BVS. Discontinuities in BVS were observed in 19.4% at six months and 14.3% at 12 months.

CONCLUSIONS

Vascular healing with BVS and BP-DES could be more device-specific than patient-specific. At follow-up, BVS presented fewer uncovered or non-apposed struts than BP-DES but more frequent and larger evaginations. Discontinuities in BVS were relatively frequent at both time points.

Biodegradable Stents for Congenital Heart Disease

The quest for an ideal biodegradable stent for both adult coronary and pediatric congenital heart disease applications continues. Over the past few years, a lot of progress has been made toward development of a dedicated pediatric biodegradable stent that can be used for congenital heart disease applications. At present, there are no biodegradable stents available for use in congenital heart disease. In this article, the authors review the different biodegradable materials and their limitations and provide an overview of the current biodegradable stents being evaluated for congenital heart disease applications.

Relation between bioresorbable scaffold sizing using QCA-Dmax and long-term clinical outcomes in 1,232 patients from three study cohorts (ABSORB Cohort B, ABSORB EXTEND, and ABSORB II)

AIMS

This study sought to investigate the long-term clinical outcomes related to scaffold sizing based on quantitative coronary angiography.

METHODS AND RESULTS

A total of 1,248 patients who received Absorb bioresorbable scaffolds in the ABSORB Cohort B, ABSORB EXTEND, and ABSORB II trials were included in the analysis. The incidence of MACE (a composite of cardiac death, any myocardial infarction [MI], and ischaemia-driven target lesion revascularisation [ID-TLR]) was analysed according to the Dmax subclassification of oversized scaffold group versus non-oversized (any undersize) scaffold group. At three years, event rates were similar in both groups in MACE (9.4% vs. 9.8%, p=0.847), target vessel MI (5.2% vs. 4.8%, p=0.795), and ID-TLR (4.8% vs. 5.8%, p=0.445). Landmark analysis after one year showed that the non-oversized scaffold group had higher rates of MACE (3.2% vs. 6.9%, log-rank p=0.004), target vessel MI (0.7% vs. 2.7%, log-rank p=0.007), and ID-TLR (2.5% vs. 4.7%, log-rank p=0.041).

CONCLUSIONS

Implantation of an undersized scaffold was associated with a higher risk of MACE between one and three years, while in the previous report an oversized scaffold was associated with a higher risk of MACE up to one year. This implies different mechanisms for early and late events after scaffold implantation.

Implantation of bioresorbable vascular scaffold for the treatment of pudendal artery stenosis and erectile dysfunction

Bioresorbable vascular scaffolds (BVS) have been designed to overcome long-term limitations of metallic drug-eluting stents including permanent metallic "caging" that might trigger late coronary adverse events. Here, we report for the first time a case of 72-year gentleman with previous coronary artery disease, treated by successful implantation of BVS (Absorb, Abbott Vascular) due to significant stenosis of internal pudenda artery and erectile dysfunction. After 2 years, BVS completely resorbed and there were no signs of pudendal artery restenosis on CT scan, whereas blood flow and sexual function improved.

Long-term outcome of first 300 implanted Absorb bioresorbable vascular scaffolds in an all-comers Middle East population

Objectives

To evaluate long-term clinical outcomes of the Absorb bioresorbable vascular scaffold (BVS) system (Abbott Vascular) in an all-comers Middle East population.

Methods

This prospective registry study included an initial set of patients with coronary lesions treated using Absorb BVS. Patients were followed for target vessel failure (TVF) including cardiac death, target vessel myocardial infarction (MI), and target lesion revascularization.

Results

A total of 217 patients (age, 55 ± 11 years; male, 169) with 300 treated lesions were included (median follow-up, 36 months [range, 26–41 months]; complete follow-up, 201 patients). Diabetes mellitus and acute coronary syndrome were present in 50% and 57% of patients, respectively. TVF rate was 32/201 (15.9%), including cardiac death in 10 (5%), target vessel MI in 13 (6.5%), and target lesion revascularization in 22 patients (10.9%). Definite or probable device thrombosis occurred in 11/201 patients (5.5%). TVF was associated with heart failure, worse ejection fraction, multi-vessel BVS, multi BVS in lesion, and total BVS length >50 mm.

Conclusions

Long-term outcome following Absorb BVS implantation in a population with high prevalence of high-risk and complex patients is acceptable, but heart failure, worse ejection fraction, and multi-vessel or long BVS implantation were associated with worse outcomes.