Bioresorbable magnesium scaffold in the treatment of simple coronary bifurcation lesions: The BIFSORB pilot II study

Abstract

Objectives: To evaluate the feasibility, safety, and healing response of a magnesiumbased bioresorbable scaffold (BRS) in the treatment of simple bifurcation lesions using the single stent provisional technique.Background: BRS may hold potential advantages in the treatment of coronary bifurcation lesions, however low radial strength and expansion capacity has been an issue with polymer-based scaffolds. The magnesium BRS may prove suitable for bifurcation treatment as its mechanical properties are closer to those of permanent metallic drug-eluting stents. Methods:The study was a proof-of-concept study with planned inclusion of 20 patients with stable angina pectoris and a bifurcation lesion involving a large side branch (SB) > 2.5 mm with less than 50% diameter stenosis. Procedure and healing response were evaluated by optical coherence tomography (OCT). The main endpoints were a composite clinical safety endpoint and an OCT healing index at 1 month (range: 0-98).Results: Eleven patients were included in the study. The study was prematurely terminated due to scaffold fractures and embolization of scaffold fragments in three cases requiring bailout stenting with drug-eluting stents. One patient underwent bypass surgery at 3 months due to stenosis proximal to the study segment. All SB were patent for 1 month. One-month OCT evaluation showed strut coverage of 96.9% and no malapposition. Scaffold fractures and uncovered jailing struts resulted in a less favorable mean OCT healing index score of 10.4 ± 9.0.Conclusions: Implanting a magnesium scaffold by the provisional technique in nontrue bifurcation lesions was associated with scaffold fracture, embolization of scaffold fragments, and a high need for bailout stenting.

Everolimus-eluting bioresorbable scaffold versus everolimus-eluting metallic stent in primary percutaneous coronary intervention of ST-segment elevation myocardial infarction: a randomized controlled trial

“…In order to describe healing of the stented segment, we sought to use a coronary stent healing index (CSHI, Supplemental Digital Content 1, http://links.lww.com/ MCA/A519) in an attempt to quantify incomplete healing. Similar scores have been attempted in other OCT investigations, but no consensus or validations of such scores exist [14,17]. CSHI, Supplemental Digital Content 1, http://links.lww.com/MCA/A519, is a weighted composite based on matched OCT images from baseline to 12-month follow-up.…”

Bioresorbable scaffolds: zebras are not striped horses

“…The available results in this subset derive from an animal study showing the feasibility of provisional stenting by Magmaris use. 4 In this issue of CCI, Barkholt et al 5 Although the study carries some good news (such as the absence of stent thrombosis and the good OCT results during follow-up), the high rate of scaffold fracture observed (27%) requires a thorough thought. Different causes, such as a collision with the OCT catheter, the POT balloon catheter, or the guiding catheter, may explain the observed scaffold damage.…”

“…In this issue of CCI , Barkholt et al 5 tested the Magmaris device in 20 patients with stable angina in bifurcation lesions (Medina 0.1.0 or 1.1.0), involving noncalcified branches. The provisional stenting technique used mandates predilation of the main branch, jailing of the side branch, postdilation, and proximal optimization technique (POT).…”