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.

Serial invasive imaging follow-up of the first clinical experience with the Magmaris magnesium bioresorbable scaffold.

OBJECTIVES: To assess the performance of the commercially available Magmaris sirolimus-eluting bioresorbable scaffold (BRS) with invasive imaging at different time points. BACKGROUND: Coronary BRS with a magnesium backbone have been recently studied as an alternative to polymeric scaffolds, providing enhanced vessel support and a faster resorption rate. We aimed to assess the performance of the commercially available Magmaris sirolimus-eluting BRS at different time points. METHODS: A prospective, single-center, nonrandomized study was performed at the Thoraxcenter, Erasmus Medical Center, Rotterdam, The Netherlands. Six patients with stable de novo coronary artery lesions underwent single-vessel revascularization with the Magmaris sirolimus-eluting BRS. Invasive follow-up including intravascular imaging using optical coherence tomography (OCT) was performed at different time points. RESULTS: At a median of 8 months (range 4-12 months) target lesion failure occurred in one patient. Angiography revealed a late lumen loss of 0.59 ± 0.39 mm, a percentage diameter stenosis of 39.65 ± 15.81%, and a binary restenosis rate of 33.3%. OCT showed a significant reduction in both minimal lumen area (MLA) and scaffold area at the site of the MLA by 43.44 ± 28.62 and 38.20 ± 25.74%, respectively. A fast and heterogeneous scaffold degradation process was found with a significant reduction of patent struts at 4-5 months. CONCLUSIONS: Our findings show that the latest iteration of magnesium BRS suffers from premature dismantling, resulting in a higher than expected decrease in MLA.

Are we curing one evil with another? A translational approach targeting the role of neoatherosclerosis in late stent failure.

Neoatherosclerosis is defined as foamy macrophage infiltration into the peri-strut or neointimal area after stent implantation, potentially leading to late stent failure through progressive atherosclerotic changes including calcification, fibroatheroma, thin-cap fibroatheroma, and rupture with stent thrombosis (ST) in advanced stages. Human autopsy as well as intravascular imaging studies have led to the understanding of neoatherosclerosis formation as a similar but significantly accelerated pathophysiology as compared to native atherosclerosis. This acceleration is mainly based on disrupted endothelial integrity with insufficient barrier function and augmented transmigration of lipids following vascular injury after coronary intervention and especially after implantation of drug-eluting stents. In this review, we summarize translational insights into disease pathophysiology and discuss therapeutic approaches to tackle this novel disease entity. We introduce a novel animal model of neoatherosclerosis alongside accompanying in vitro experiments, which show impaired endothelial integrity causing increased permeability for low-density lipoprotein cholesterol resulting in foam cell transformation of human monocytes. In addition, we discuss novel intravascular imaging surrogates to improve reliable diagnosis of early stage neoatherosclerosis. Finally, a therapeutic approach to prevent in-stent neoatherosclerosis with magnesium-based bioresorbable scaffolds and systemic statin treatment demonstrated the potential to improve arterial healing and re-endothelialization, leading to significantly mitigated neoatherosclerosis formation in an animal model of neoatherosclerosis.

La neoateroesclerosis se define como infiltración de macrófagos espumosos en la zona periprotésica o de la neoíntima tras una implantación de stent, lo cual posiblemente derive en un fracaso tardío del stent mediante cambios ateroescleróticos progresivos, incluidos la calcificación, fibroateromas, fibroateromas de cápsula fina (FACF) y trombosis del stent (TS). Gracias a los estudios de autopsia humana y de imagen intravascular se ha podido comprender la formación de la neoateroesclerosis de una manera fisiopatológica similar a la ateroesclerosis nativa pero significativamente acelerada. Esta aceleración se basa principalmente en la alteración de la integridad endotelial con una función de barrera insuficiente y una mayor transmigración de lípidos a consecuencia de una lesión vascular tras una intervención coronaria y, especialmente, tras la implantación de stents farmacoactivos. En este artículo ofrecemos un resumen de las perspectivas translacionales sobre la fisiopatología de la enfermedad y analizamos los enfoques terapéuticos para abordar esta nueva enfermedad. Presentamos un modelo animal de neoateroesclerosis innovador junto con experimentos in vitro complementarios, en los cuales se pone de manifiesto que la integridad endotelial dañada causa una mayor permeabilidad para el colesterol de las LDL (LDL), lo que da lugar a que los monocitos se transformen en células espumosas. Asimismo, comentamos los criterios indirectos de valoración de imagen intravascular a fin de mejorar el diagnóstico fiable de la neoateroesclerosis en fase inicial. Por último, en un enfoque terapéutico para prevenir la neoateroesclerosis del stent con andamios de magnesio biorreabsorbibles (BRS) y un tratamiento sistémico con estatinas se demostró la posibilidad de mejorar la cicatrización y la reendotelización arteriales, lo que derivó en la formación de neoateroesclerosis significativamente más lenta en un modelo animal de neoateroesclerosis.

Two-Year Outcomes for Patients with Non-ST-Elevation Acute Coronary Syndrome Treated with Magmaris and Absorb Bioresorbable Scaffolds in Large-Vessel Lesions.

BACKGROUND: The acute coronary syndrome (ACS) continues to be a fundamental indication for revascularization by percutaneous coronary intervention (PCI). Drug-eluting stent (DES) implantation remains a part of contemporary practice but permanent caging of the vascular structure with the metallic stent structure may increase the rate of device-related adverse clinical events. As an alternative to classic metallic DESs, the bioresorbable scaffolds (BRSs) have emerged as a temporary vascular support technology. We evaluated the mid-term outcomes of two generations of bioresorbable scaffolds-Absorb (Abbott-Vascular, Chicago, IL, USA) and Magmaris (Biotronik, Germany)-in patients with non-ST-elevation ACS. METHODS: The study cohort consisted of 193 subjects after Magmaris implantation and 160 patients following Absorb implantation in large-vessel lesions. RESULTS: At 2 years, a significantly lower rate of a primary outcome (cardiac death, myocardial infarction, stent thrombosis) was observed with Magmaris (5.2% vs. 15%; p = 0.002). In addition, we observed a significantly lower rate of MI in the target vessel (2.6% vs. 9.4%; p = 0.009) and a lower rate of scaffold thrombosis (0% vs. 3.7%; p = 0.008). The TLF rate between the two groups was not significantly different. CONCLUSION: Magmaris demonstrated a good safety profile and more favorable clinical outcomes when compared to Absorb in patients with non-ST-elevation ACS.

Magnesium bioresorbable scaffold (Magmaris) versus polymer biodegradable ultrathin drug-eluting stent (Ultimaster) in acute coronary syndrome. Mid-term outcomes (2 years).

Introduction: Acute coronary syndrome (ACS) is a well-known risk factor for adverse clinical outcomes in percutaneous coronary intervention (PCI). Therefore, evaluation of coronary stents in this challenging clinical scenario can provide unique information on device safety and efficacy. Bioresorbable scaffolds (BRS) were designed to overcome long-term complications related to permanent vessel caging with a permanent metallic drug-eluting stent (DES). Aim: We designed this study to evaluate the mid-term safety and efficiency of the Magmaris BRS in comparison to the leading new-generation ultrathin DES Ultimaster in the ACS population. Material and methods: We present a retrospective analysis of 2-year follow-up data. The primary outcomes consisted of death from cardiac causes, myocardial infarction, and in-stent thrombosis. The second main study endpoint was defined as target-lesion failure (TLF). Results: The study population consisted of two cohorts, the first of 193 patients treated with Magmaris implantation and the second of 169 patients treated with Ultimaster implantation. At the 2-year follow-up, there were no significant differences in both study cohorts in terms of primary outcome (5.1% vs. 11%; p = 0.051), and TLF (5.6% vs. 8%, p = 0.41). Conclusions: Treatment with a second-generation BRS (Magmaris) versus a novel second-generation DES (Ultimaster) in non-ST-elevation acute coronary syndrome (NSTE-ACS) was associated with similar rates of target lesion failure at 2-year follow-up.

Mid-term safe and effective profile of the Magmaris scaffold in percutaneous coronary intervention: a prospective, single-center study.

Introduction: Significant advances have been made in the diagnosis and treatment of coronary artery disease over the years. New generations of scaffolds containing novel material and eluting drug have produced one of the most significant advancements in coronary intervention. The newest generation would be Magmaris with a magnesium frame and a sirolimus cover. Methods: From July 2018 to August 2020, 58 patients treated with Magmaris at the University Medical Center Ho Chi Minh City were enrolled in this study. Results: A total of 60 lesions were stented, 60.3% of which were left anterior descending (LAD) lesions. There was no in-hospital event. Within 1 year after discharge, we noted one myocardial infarction event that required target-lesion revascularization, one stroke event, one non-target-lesion revascularization patient, two target-vessel revascularization patients, and one in-stent thrombosis. Among them, one myocardial infarction occurrence, one non-target-lesion revascularization, and one in-stent thrombosis event were recorded within the first 30 days after discharge. Conclusion: In conclusion, the Magmaris scaffold is a safe and effective option for structural procedures performed with imaging device support, particularly intravascular ultrasound.

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.

Mid-term safety and efficacy of magnesium bioresorbable vascular scaffolds - magmaris in diabetic population. 2-Years outcome in acute coronary syndrome cohort.

BACKGROUND: Diabetes type 2 is one of the strongest risk factors affecting coronary artery disease (CAD) and is also a marker of poor short and long-term prognosis in subjects with acute coronary syndrome (ACS) treated with percutaneous coronary intervention (PCI) with subsequent drug-eluting stent (DES) implantation. Chronic local vascular inflammation along with endothelial dysfunction is postulated to be the pathophysiological background of unfavorable results. The second generation of metallic magnesium BRS -Magmaris (Biotronik, Berlin, Germany) had been introduced to clinical practice to overcome these limitations. METHODS: We evaluated 2-years clinical outcomes after Magmaris BRS implantation in NSTE-ACS diabetic (n-72) and non-diabetic (n-121) cohorts. RESULTS: No significant differences between diabetic and non-diabetes cohorts were noticed in terms of Primary Outcome (cardiac death, myocardial infarction, stent thrombosis) (8.1% vs 3.3% p = 0.182) and Principal secondary outcome - TLF- target lesion failure (9.5% vs 3.3% p = 0.106) at 2-years follow-up. CONCLUSIONS: 2-years outcome suggests good safety and efficacy of the magnesium BRS (Magmaris) in NSTE- ACS and concomitant DM. Nevertheless, there is a strong need for large multicenter, randomized, prospective studies for a full assessment of this novel device in diabetic patients with ACS.

The Resorbable Magnesium Scaffold Magmaris in Acute Coronary Syndrome: An Appraisal of Evidence and User Group Guidance.

Bioresorbable scaffolds provide transient vessel support without the long-term limitations of permanent metallic drug-eluting stents. The sirolimus-eluting resorbable magnesium scaffold Magmaris is the only CE-marked metallic bioresorbable scaffold and provides short-term lumen support before being completely bioresorbed. To date, clinical trial results have demonstrated low adverse event rates in patients with simple coronary lesions. Seven European centers with large experience in Magmaris implantation, combined efforts in an informal collaboration to evaluate and appraise clinical data currently available regarding the performance of Magmaris in patients presenting with acute coronary syndromes, and to supply user-advice on patient selection and optimal implantation practice.

Magmaris Resorbable Magnesium Scaffold Versus Conventional Drug-Eluting Stent in ST-Segment Elevation Myocardial Infarction: 1-Year Results of a Propensity-Score-Matching Comparison.

Magmaris® (Biotronik AG, Switzerland) is the first RMS and early experience has shown promising results in stable coronary artery disease. Acute coronary syndromes have been hypothesized as a potential target group for bioresorbable scaffolds, but the efficacy and safety of RMS has not been extensively studied in ST-segment elevation myocardial infarction (STEMI). BEST-MAG is a prospective multicenter trial designed to evaluate optical coherence tomography (OCT-)guided implantation of resorbable magnesium scaffold (RMS) in STEMI. Consecutive STEMI patients fulfilling inclusion/exclusion criteria were treated with RMS following a standardized OCT-based implantation technique including systematic pre- and post-dilatation, and baseline plus final OCT imaging. The primary endpoint was a device oriented composite endpoint (DOCE) including cardiac death, target vessel myocardial infarction (TV-MI) and target lesion revascularization (TLR) within 12 months. Clinical outcomes were compared after propensity score matching (PSM) to the results of the randomized controlled BIOSTEMI trial comparing biodegradable polymer sirolimus eluting (BP-SES) and durable polymer everolimus eluting stents (DP-EES) in STEMI. Between 15th February 2019 and 25th May 2020, 30 patients were included in 5 centers. Procedural success was achieved in all cases based on OCT control with final scaffold expansion of 82 ± 11%. At twelve-months, DOCE rate was 13.3% (n = 4), including 4 cases of TLR (13.3%) and one case of TV-MI (3.3%). No cardiac death occurred, and no scaffold thrombosis (ScT) was observed. Using PSM, DOCE rates in BP-SES and DP-EES groups were 10% and 6% respectively and TLR rates were 3.3% and 0.0%. In this study, OCT-guided RMS implantation in selected STEMI patients appeared feasible but was associated with numerically higher rates of TLR as compared with conventional drug-eluting stents, although the limited number of patients included in this analysis does not allow drawing statistically significant conclusions.