Restenosis in a Collapsed Magnesium Bioresorbable Scaffold

Section: Discussionsupporting

confidence: 48%

Early collapse causing stenosis in a resorbable magnesium scaffold

Marynissen

McCutcheon

Bennett

2018

“…Complete SA and neointimal volumes throughout the scaffolded segment could not be determined due to the difficulty in recognizing patent struts; however, when the SA was analyzable, a significant reduction of SA was found compared to the postimplantation result at the same location. These findings are in line with seven recently published case reports on severe lumen reduction and scaffold collapse after Magmaris BRS implantation . Furthermore, acute recoil was only 5.3%, in line with current generation metallic DES and BVS .…”

Section: Discussionsupporting

confidence: 91%

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

Forero

Zandvoort

Masdjedi

et al. 2019

Objectives: To assess the performance of the commercially available Magmaris sirolimuseluting 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. K E Y W O R D S bioresorbable scaffolds, constrictive remodeling, Magmaris sirolimus-eluting bioresorbable scaffold, scaffold bioresorption, scaffold collapse, scaffold recoil Abbreviations: AMS, absorbable magnesium scaffolds; BRS, bioresorbable scaffold; DAPT, dual antiplatelet therapy; DES, drug-eluting stent; DS, diameter stenosis; LA, lumen area; LLL, late lumen loss; MLA, minimal lumen area; MSA, minimal scaffold area; NC, noncompliant; OCT, optical coherence tomography; post-PCI, post-percutaneous coronary intervention; pre-PCI, prepercutaneous coronary intervention; QCA, quantitative coronary analysis; RVD, reference vessel diameter; SA, scaffold area; SE-MEA, scaffold expansion according to manufacturer's expected area; SE-RVA, scaffold expansion according to reference vessel area.

“…The authors suggested underexpansion as the main mechanism of stent failure. In addition, Barkholt et al described a RMS restenosis 7 months after implantation. In this case, based on OCT analysis, the authors suggested the late collapse of the scaffold (due to the fast degradation time leading to loss of radial strength) as the main mechanism leading to restenosis.…”

Section: Discussionmentioning

confidence: 99%

Early restenosis of resorbable magnesium scaffolds: Optical coherence tomography findings

García-Guimarães

Antuña

Cuesta

et al. 2018

Resorbable Magnesium Scaffolds (RMS) represent an interesting alternative to current drug‐eluting stents. Current data from clinical trials seems to confirm good performance of these new devices with low rates of late device failure. Little is known about mechanisms leading to RMS failure. Herein, we present the first description of an early RMS in‐scaffold restenosis. Optical coherence tomography (OCT) analysis at implantation detected acute non‐severe malapposition and underexpansion as main promoters of RMS failure. OCT during in‐scaffold restenosis intervention confirmed early severe neointimal proliferation and RMS late recoil and dismantling as the main mechanisms of device failure. We hypothesize that the fast resorption process of RMS may lead to an early loss of radial strength, that could favor late recoil, acquired underexpansion, device dismantling and might interact with distribution of sirolimus. This case also illustrates that OCT is pivotal to unravel both acute and acquired mechanisms related to RMS failure.