MGuard Stent meets primary endpoint of MASTER trial, significantly improving prospects of heart attack survival


The MGuard Embolic Protection Stent (EPS) (InspireMD) was shown to be significantly superior when compared to standard bare metal and drug eluting stents in achieving complete ST resolution and restoring normal blood flow. According to results from the MASTER trial presented by Gregg W Stone and director of the Cardiovascular Research and Education Center for Interventional Vascular Therapy at New York-Presbyterian Hospital/Columbia University Medical Center, at a Late Breaking Trials Sessions at TCT. 

The MASTER trial (MGuard for acute ST elevation reperfusion) randomised 432 patients undergoing emergency coronary intervention for potentially fatal heart attacks at 50 centres in nine countries. Patients are being followed for one year. The patients were implanted with the MGuard EPS (217) and either bare metal or drug eluting stents (216).

The study met its primary endpoint (proportion of patients with ST segment resolution of≥ 70%, measured at 60 to 90 minutes post procedure), showing the MGuard EPS was significantly superior to the control arm of bare metal and drug eluting stents in the treatment of heart attack patients.

Key results:

● Significantly more patients treated with the MGuard EPS achieved complete ST resolution (a measure of blood flow restoration to the heart muscle) compared to control arm (57.8% vs. 44.7%, P=0.008), a relative improvement of 29%.

● When compared to control, the MGuard EPS showed a significant improvement in coronary artery blood flow, including: (1) superior rates of restoring normal blood flow (TIMI-3 flow) (91.7% vs. 82.9%, P=0.006, a relative improvement of 10.6%); and (2) significantly less incomplete blood flow (TIMI-0/1 flow) post PCI (1.8% vs. 5.6%, P=0.01, a relative improvement of 67.9%).

● The trial showed a trend toward lower mortality (0% vs. 1.9%, P=0.06) at 30 days and smaller infarct size as measured by post procedure cardiac MRI (17.1gr vs. 22.3gr, p=0.27) in the MGuard EPS arm versus control.

● There was no difference between the groups in the secondary endpoint of myocardial blush grade (MBG), which is an angiographic measure of blood flow to the cardiac muscle (MBG2/3 83.9% vs. 84.7%, P=0.81).

“I was impressed with the performance of the MGuard Embolic Protection Stent in the MASTER trial,” said Stone. “Compared to standard stents, the MGuard is the first stent in a randomised trial shown to restore complete ST-segment resolution in a higher proportion of patients, a key predictor of myocardial salvage and long-term survival in STEMI patients.”

Details of the MASTER trial were published online in the Journal of American College of Cardiology (JACC).

MGuard EPS is CE mark approved.