In the trial, a 90% survival rate was reported, continuing the initial positive trend of 99% survival after 30 days. Patients were treated with the Direct Flow Medical transcatheter aortic valve system and experienced excellent overall hemodynamic results, as well as a low rate of procedural complications.
At 12 months, 100% of patients experienced mild or less aortic regurgitation (AR), with 77% having none or trace AR. The DISCOVER Trial 12 month outcomes were presented today by principal investigator Dr Joaquim Schofer from the Medical Care Center, Hamburg, Germany.
The fully repositionable and retrievable Direct Flow Medical system is designed to treat patients with severe aortic stenosis who are at high or extreme surgical risk, while reducing the risk of post-procedural AR, a strong predictor of long-term mortality.
The system addresses this clinical concern by sealing the annulus and enabling complete assessment of hemodynamic performance with unlimited repositioning of the valve after full deployment. It avoids both rapid pacing of the heart during deployment and post-dilatation following placement, minimizing the risk of hemodynamic instability for patients.
The system includes a distinctive heart valve with a metal-free frame, delivered transfemorally via a flexible, 18 French delivery system for all sizes (23mm, 25mm, 27mm and 29mm).
In the DISCOVER Trial, the mean transthoracic echo gradient at 30 days was 12.5mmHg and remained low at 12 months (12.3mmHg). All hemodynamic outcomes were assessed and reported by an independent imaging core laboratory.
The VARC Defined Device Success rate was 91%. At 30 days, 83% of patients had improved by more than one New York Heart Association (NYHA) functional class and this was maintained at 12 months, with 95% classified as NYHA Class I/II.
The initial DISCOVER Trial was a prospective, multicenter study conducted at nine European sites of 100 patients with severe aortic valve stenosis who required replacement of their native aortic valve but were at extreme risk for open surgical repair.
The trial has since expanded to additional sites and patients, enrolling patients in 23mm valve and 29mm valve trial arms. The 29mm valve received CE Mark in December 2013 and the 23mm valve is pending CE Mark approval.
The Direct Flow Medical system received the CE Mark in January 2013 and is currently available commercially in Europe.