Comparison of acute versus stable coronary syndrome in patients treated with the Magmaris scaffold: Two-year results from the Magmaris Multicenter Italian Registry

BACKGROUND

The magnesium Magmaris scaffold is the latest resorbable technology with low thrombogenicity, short scaffolding time, and almost complete resorption at 12 months (95 %). As compared with stable coronary artery disease (SCAD), acute coronary syndrome (ACS) is associated with increased risk of adverse clinical outcome after percutaneous coronary intervention. We analyzed the data of the Magmaris Multicenter Italian Registry to compare clinical outcomes in SCAD versus ACS patients.

METHODS

We evaluated the 24-month rates of target lesion failure (TLF) and scaffold thrombosis (ST). Device implantation procedures were performed according to the manufacturer's recommendations (proper patient/lesion selection, pre-dilatation, proper scaffold sizing, and post-dilatation). Dual antiplatelet therapy was terminated after 12 months.

RESULTS

Data from 207 patients (145 SCAD and 62 ACS) were collected from July 2016 to June 2018. The 2-year follow-up compliance was 92.8 % (192 patients). At 2 years, TLF rates were 7.4 % in the SCAD group and 8.8 % in the ACS group (p = 0.7); ST rates were 0 % in the SCAD group and 1.8 % in the ACS group (p = 0.1).

CONCLUSION

The 2-year clinical results from the Magmaris Multicenter Italian Registry are favorable in terms of TLF and ST, indicating the safety and effectiveness of the Magmaris scaffold in both SCAD and ACS patients.

Bioresorbable Magnesium-Based Stent: Real-World Clinical Experience and Feasibility of Follow-Up by Coronary Computed Tomography: A New Window to Look at New Scaffolds

(1) Background: The diagnostic accuracy of coronary computed tomography angiography (CCTA) for coronary artery disease (CAD) has greatly improved so CCTA represents a transition in the care of patients suffering from CAD. Magnesium-based bioresorbable stents (Mg-BRS) secure acute percutaneous coronary intervention (PCI) results without leaving, in the long term, a metallic caging effect. The purpose of this real-world study was to assess clinical and CCTA medium- and long-term follow-up of all our patients with implanted Mg-BRS. (2) Methods: The patency of 52 Mg-BRS implanted in 44 patients with de novo lesions (24 of which had acute coronary syndrome (ACS)) was evaluated by CCTA and compared to quantitative coronary angiography (QCA) post-implantation. (3) Results: ten events including four deaths occurred during a median follow-up of 48 months. CCTA was interpretable and in-stent measurements were successful at follow-up without being hindered by the stent strut's "blooming effect". Minimal in-stent diameters on CCTA were found to be 1.03 ± 0.60 mm smaller than the expected diameter after post-dilation on implantation (p < 0.05), a difference not found in comparing CCTA and QCA. (4) Conclusions: CCTA follow-up of implanted Mg-BRS is fully interpretable and we confirm the long-term Mg-BRS safety profile.

The mega COMBO collaboration: An individual patient data pooled analysis of patients undergoing PCI with COMBO stent

BACKGROUND

COMBO (OrbusNeich Medical, Hong Kong) is a dual-therapy coronary stent featuring sirolimus as antiproliferative drug and an anti-CD34+ antibody coating to attract endothelial progenitor cells favoring rapid stent re-endothelization. The Mega COMBO collaboration aimed to evaluate the performance of the COMBO stent in a large contemporary cohort of patients undergoing percutaneous coronary intervention (PCI).

METHODS

Patient-level data of subjects undergoing PCI with the COMBO stent from the REMEDEE-Trial, REMEDEE-OCT, HARMONEE, REDUCE, SORT OUT X, REMEDEE-Registry and MASCOT studies were pooled together. The primary endpoint was 1-year target lesion failure (TLF), a composite of cardiovascular death, target vessel myocardial infarction (TV-MI) or clinically driven target lesion revascularization (CD-TLR). Secondary outcomes were the individual components of the primary endpoint and stent thrombosis (ST). Endpoints were evaluated against performance goals based on the EAPCI (the European Association of Percutaneous Coronary Intervention) recommendations for new drug-eluting stents.

RESULTS

A total of 6753 patients (mean age 63.7 ± 11.4 years, 23% women) were included. At 1-year follow-up, TLF occurred in 303 (4.6%) patients. The rates of cardiovascular death, TV-MI, and CD-TLR were 1.3%, 1.8%, and 2.5%, respectively. The rate of definite/probable ST was 0.73%, early ST (<1 month) was 0.48%, while late ST (1-12 months) was 0.26%. The performance goals were met for all of the evaluated endpoints.

CONCLUSIONS

This large patient-level pooled analysis provides a comprehensive outline of the performance of the dual-therapy COMBO stent. The low rates of primary and secondary endpoints suggest that this stent technology may be a good alternative to other contemporary drug eluting coronary stent platforms.

Mg-based materials diminish tumor spreading and cancer metastases

Cancer metastases are the most common causes of cancer-related deaths. The formation of secondary tumors at different sites in the human body can impair multiple organ function and dramatically decrease the survival of the patients. In this stage, it is difficulty to treat tumor growth and spreading due to arising therapy resistances. Therefore, it is important to prevent cancer metastases and to increase subsequent cancer therapy success. Cancer metastases are conventionally treated with radiation or chemotherapy. However, these treatments elicit lots of side effects, wherefore novel local treatment approaches are currently discussed. Recent studies already showed anticancer activity of specially designed degradable magnesium (Mg) alloys by reducing the cancer cell proliferation. In this work, we investigated the impact of these Mg-based materials on different steps of the metastatic cascade including cancer cell migration, invasion, and cancer-induced angiogenesis. Both, Mg and Mg–6Ag reduced cell migration and invasion of osteosarcoma cells in coculture with fibroblasts. Furthermore, the Mg-based materials used in this study diminished the cancer-induced angiogenesis. Endothelial cells incubated with conditioned media obtained from these Mg and Mg–6Ag showed a reduced cell layer permeability, a reduced proliferation and inhibited cell migration. The tube formation as a last step of angiogenesis was stimulated with the presence of Mg under normoxia and diminished under hypoxia.

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Magnesium (Mg)-based material degradation decrease cell migration and invasion of an osteosarcoma coculture.

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Mg-based material degradation products reduce cancer-induced angiogenesis at an early stage.

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These materials may reduce secondary tumor formation and metastases.

Magnesium Bioresorbable Scaffold (BRS) Magmaris vs Biodegradable Polymer DES Ultimaster in NSTE-ACS Population-12-Month Clinical Outcome

Background

Percutaneous coronary intervention (PCI) in the acute coronary syndrome (ACS) setting is associated with a greater probability of device failure. The currently ongoing development of new scaffold technologies has concentrated an effort on improving the PCI outcomes, including the use of new biodegradable materials. This pilot study evaluates the performance of a magnesium bioresorbable scaffold (Magmaris, Biotronik, Germany) in comparison to the sirolimus-eluting bioresorbable polymer stents (BP-SES) (Ultimaster, Terumo, Japan) in the NSTE-ACS setting.

Methods

The population of this pilot comprised 362 patients assigned to one of two arms (193-Magmaris vs 169-Ultimaster). The data regarding the primary outcome comprised of death from cardiac causes, myocardial infarction, and stent thrombosis, along with target-lesion failure (TLF) and other clinical events was collected in the 1-yearfollow-up.

Results

There were no statistically significant differences in clinical outcomes in the short term (30 days) or in the 1-yearfollow-up between both groups.

Conclusion

At 12 months, there were no statistically significant differences between the Magmaris and Ultimaster for composed endpoints or the TLF.

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.

Effect of silver in thermal treatments of Fe-Mn-C degradable metals: Implications for stent processing

Twinning-induced plasticity (TWIP) steels are considered excellent materials for manufacturing products requiring extremely high mechanical properties for various applications including thin medical devices, such as biodegradable intravascular stents. It is also proven that the addition of Ag can guarantee an appropriate degradation while implanted in human body without affecting its bioactive properties. In order to develop an optimized manufacturing process for thin stents, the effect of Ag on the recrystallization behavior of TWIP steels needs to be elucidated. This is of major importance since manufacturing stents involves several intermediate recrystallization annealing treatments. In this work, the recrystallization mechanism of two Fe-Mn-C steels with and without Ag was thoroughly investigated by microstructural and mechanical analyses. It was observed that Ag promoted a finer microstructure with a different texture evolution, while the recrystallization kinetics resulted unaffected. The presence of Ag also reduced the effectiveness of the recrystallization treatment. This behavior was attributed to the presence of Ag-rich second phase particles, precipitation of carbides and to the preferential development of grains possessing a {111} orientation upon thermal treatment. The prominence of {111} grains can also give rise to premature twinning, explaining the role of Ag in reducing the ductility of TWIP steels already observed in other works. Furthermore, in vitro biological performances were unaffected by Ag. These findings could allow the design of efficient treatments for supporting the transformation of Fe-Mn-C steels alloyed with Ag into commercial products.

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Recrystallization of a TWIP steel is hampered by the presence of Ag and carbides.

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Ag promotes preferential formation of {111} grains during thermal treatments.

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Ag broadens the Schmid factor distribution, leading to a reduction in ductility.

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Ag does not affect cytotoxicity and hemocompatibility.

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Annealing treatment above 900 °C is required for the Fe-Mn-C-Ag system.

Biodegradable Polymer DES (Ultimaster) vs. Magnesium Bioresorbable Scaffold (BRS Magmaris) in Diabetic Population with NSTE-ACS: A One-Year Clinical Outcome of Two Sirolimus-Eluting Stents

BACKGROUND

Cardiovascular disease (CVD) with significant involvement of coronary artery disease (CAD) remains a major cause of death and disability among the diabetic population. Although percutaneous coronary intervention (PCI) continues to evolve, type 2 diabetes mellitus (T2DM) is a well-established marker of poor clinical prognosis after PCI, which is mainly attributed to the rapid progression of atherosclerosis requiring recurrent revascularizations. Hence, the use of bioresorbable materials could provide some solution to this problem. Material and Methods. The study was divided into two arms. For the first one, we qualified 169 patients with NSTE-ACS treated with PCI who received the drug-eluting stent (DES) coated with a biodegradable polymer Ultimaster (Terumo, Tokyo, Japan). The second arm was composed of 193 patients with ACS who underwent PCI with a magnesium bioresorbable scaffold Magmaris (Biotronik, Berlin, Germany). Both arms were divided into two subsequent groups: the T2DM (59 and 72) and the non-DM (110 and 121, respectively). The primary outcomes were cardiovascular death, myocardial infarction, and in-stent thrombosis. The main secondary outcomes included target lesion failure (TLF) and were recorded at a 1-year-follow-up.

RESULTS

There were no significant differences between the diabetic and nondiabetic populations in primary endpoints or main secondary endpoints (TLF, scaffold restenosis, death from any reason, and other cardiovascular events) either in the Ultimaster or Magmaris group. At a 1-year-follow-up, the primary endpoint in the DM t.2 population was recorded in 2.7% Ultimaster vs. 5.1% Magmaris, respectively. At the same time, the TLF occurred in the diabetic group in 4.1% Magmaris and 3.3% in the Ultimaster arm, respectively.

CONCLUSION

Both, Ultimaster and Magmaris revealed relative safety and efficiency at a one-year follow-up in the diabetic population in ACS settings. The observed rates of TLF were low, which combined with a lack of in-stent thrombosis suggests that both investigated devices might be an interesting therapeutic option for diabetics with ACS. Nevertheless, further large randomized clinical trials are needed to confirm fully our results.

Six-Month Long In Vitro Degradation Tests of Biodegradable Twinning-Induced Plasticity Steels Alloyed with Ag for Stent Applications

Twinning-induced plasticity (TWIP) Fe-Mn-C steels are biodegradable metals with far superior mechanical properties to any biodegradable metal, including Mg alloys, used in commercially available devices. For this reason, the use of Fe-Mn-C alloys to produce thinner and thinner implants can be exploited for overcoming the device size limitations that biodegradable stents still present. However, Fe-Mn steels are known to form a phosphate layer on their surface over long implantation times in animals, preventing device degradation in the required timeframe. The introduction of second phases in such alloys to promote galvanic coupling showed a short-term promise, and particularly the use of Ag looked especially effective. Nonetheless, the evolution of the corrosion mechanism of quaternary Fe-Mn-C-Ag alloys over time is still unknown. This study aims at understanding how corrosion changes over time for a TWIP steel alloyed with Ag using a simple static immersion setup. The presence of Ag promoted some galvanic coupling just in the first week of immersion; this effect was then suppressed by the formation of a mixed carbonate/hydroxide layer. This layer partly detached after 2 months and was replaced by a stable phosphate layer, over which a new carbonate/hydroxide formed after 4 months, effectively hindering the sample degradation. Attachment of phosphates to the surface matches 1-year outcomes from animal tests reported by other authors, but this phenomenon cannot be predicted using immersion up to 28 days. These results demonstrate that immersion tests of Fe-based degradable alloys can be related to animal tests only when they are carried out for a sufficiently long time and that galvanic coupling with Ag is not a viable strategy in the long term. Future works should focus more on surface modifications to control the interfacial behavior rather than alloying in the bulk.

BIOSOLVE-IV-registry: Safety and performance of the Magmaris scaffold: 12-month outcomes of the first cohort of 1,075 patients

OBJECTIVES

We aimed to assess the safety and performance of the Magmaris sirolimus-eluting bioresorbable magnesium scaffold in a large patient population.

BACKGROUND

Magmaris has shown good outcomes in small-sized controlled trials, but further data are needed to confirm its usability, safety, and performance.

METHODS

BIOSOLVE-IV is an international, single arm, multicenter registry including patients with a maximum of two single de novo lesions. Follow-up is scheduled up to 5 years; the primary outcome is target lesion failure (TLF) at 12 months.

RESULTS

A total of 1,075 patients with 1,121 lesions were enrolled. Mean patient age was 61.3 ± 10.5 years and 19.2% (n = 206) presented with non-ST-elevation myocardial infarction (NSTEMI). Lesions were 3.2 ± 0.3 mm in diameter and 14.9 ± 4.2 mm long; 5.1% (n = 57) were bifurcation lesions. Device success was 97.3% (n = 1,129) and procedure success 98.9% (n = 1,063). The Kaplan-Meier estimate of TLF at 12 months was 4.3% [95% confidence interval, CI: 3.2, 5.7] consisting of 3.9% target lesion revascularizations, 0.2% cardiac death, and 1.1% target-vessel myocardial infarction. Definite/probable scaffold thrombosis occurred in five patients (0.5% [95% CI: 0.2, 1.1]), thereof four after early discontinuation of antiplatelet/anticoagulation therapy.

CONCLUSION

BIOSOLVE-IV confirms the safety and performance of the Magmaris scaffold in a large population with excellent device and procedure success and a very good safety profile up to 12 months in a low-risk population.

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.

Bioresorbable Scaffolds: Contemporary Status and Future Directions

Percutaneous coronary intervention, which is safe, effective, and timely, has become an important treatment for coronary artery diseases and has been widely used in clinical practice. However, there are still some problems that urgently need to be solved. Permanent vessel caging through metallic implants not only prevents the process of positive vessel remodeling and the restoration of vascular physiology but also makes the future revascularization of target vessels more difficult. Bioresorbable scaffolds (BRSs) have been developed as a potential solution to avoid the above adverse reactions caused by permanent metallic devices. BRSs provide temporary support to the vessel wall in the short term and then gradually degrade over time to restore the natural state of coronary arteries. Nonetheless, long-term follow-up of large-scale trials has drawn considerable attention to the safety of BRSs, and the significantly increased risk of late scaffold thrombosis (ScT) limits its clinical application. In this review, we summarize the current status and clinical experiences of BRSs to understand the application prospects and limitations of these devices. In addition, we focus on ScT after implantation, as it is currently the primary drawback of BRS. We also analyze the causes of ScT and discuss improvements required to overcome this serious drawback and to move the field forward.

One-Year OCT Follow-Up Results of Overlapping Resorbable Magnesium Scaffolds: Mind the Gap!

In this paper we are reporting an unexpected evolution after multiple Resorbable Magnesium Scaffolds (RMS) implantations in overlap.

The coronary resorbable magnesium scaffold Magmaris®: what we have learnt (so far…)

Bioresorbable scaffold (BRS) technology provides transient vessel support with drug-delivery capability without the long-term limitations of the permanent metallic drug-eluting stents (DES). Numerous scaffolds have been developed and investigated by device manufacturers, many of which, due to device deficiencies, have fallen by the wayside. This short review will focus on the resorbable magnesium scaffold Magmaris^® the only metallic bioresorbable scaffold currently available, providing an evaluation of the most up to date clinical data whilst also briefly highlighting learning points regarding the ideal patient and lesion choice and optimal implantation technique.

Bioresorbable Vascular Scaffolds-Dead End or Still a Rough Diamond?

Percutaneous coronary interventions with stent-based restorations of vessel patency have become the gold standard in the treatment of acute coronary states. Bioresorbable vascular scaffolds (BVS) have been designed to combine the efficiency of drug-eluting stents (DES) at the time of implantation and the advantages of a lack of foreign body afterwards. Complete resolution of the scaffold was intended to enable the restoration of vasomotor function and reduce the risk of device thrombosis. While early reports demonstrated superiority of BVS over DES, larger-scale application and longer observation exposed major concerns about their use, including lower radial strength and higher risk of thrombosis resulting in higher rate of major adverse cardiac events. Further focus on procedural details and research on the second generation of BVS with novel properties did not allow to unequivocally challenge position of DES. Nevertheless, BVS still have a chance to present superiority in distinctive indications. This review presents an outlook on the available first and second generation BVS and a summary of results of clinical trials on their use. It discusses explanations for unfavorable outcomes, proposed enhancement techniques and a potential niche for the use of BVS.

Magmaris resorbable magnesium scaffold for the treatment of coronary heart disease: overview of its safety and efficacy

Introduction: Bioresorbable scaffold technology provides transient vessel support with drug-delivery capability without the long-term limitations of the permanent metallic drug-eluting stents (DES). The technology has the potential to overcome many of the safety concerns associated with metallic DES, such as hypersensitivity reactions, late stent thrombosis and progression of atherosclerosis within the stented segment (i.e. neoatherosclerosis). Areas covered: The sirolimus-eluting resorbable magnesium scaffold Magmaris is the only metallic CE-marked resorbable scaffold currently available. This magnesium scaffold is designed for providing a short-term lumen support (up to 3 months) before being completely bioresorbed, eliminating the permanent caging typical of the metallic DES. This review will focus on the device development and characteristics, currently available clinical efficacy and safety data, and potential future perspectives. Expert opinion: The first clinical studies testing this device in a small number of patients have shown promising results with good clinical and safety outcomes up to 3 years' clinical follow-up, supporting the use of Magmaris in simple coronary artery disease.