Direct Flow Medical Transcatheter Aortic Valve System DISCOVER Trial Results At ACC

New patents for Direct Flow's TAVI system

In short

Transcatheter heart valve company Direct Flow Medical®, Inc., has been trumpeting the DISCOVER Trial results presented Sunday at the American College of Cardiology (ACC) Annual Meeting. In the study, patients treated with the Direct Flow Medical® Transcatheter Aortic Valve System achieved excellent survivability and sustained hemodynamic improvements with minimal occurrence of aortic regurgitation at six months.

Also presented was a larger cohort of 54 patients at 30 days that continued to demonstrate excellent outcomes.


We’ve covered Direct Flow’s take on what transcatheter valve technology ought to look like. Their ingenious device, featuring two “inflatable” rings rather than a metal stent/scaffold shoots straight at the target of reducing paravalvular leakage, so the clinical results are fascinating.

The DISCOVER Trial is a prospective, multicenter study of up to 100 patients conducted at up to 10 European sites of patients with severe aortic valve stenosis who require replacement of their native aortic valve but are at extreme risk for open surgical repair. The heart valve was delivered transfemorally via a flexible, 18 French delivery system.

30-day and six-month outcomes were presented by trial investigator Azeem Latib, MD, from San Raffaele Scientific Institute in Milan, Italy in a podium presentation. In 54 patients, there was 98 percent freedom from all-cause mortality at 30 days. The six-month results comprised from the pre-specified CE Mark Cohort demonstrated 92 percent freedom from all-cause mortality. The average age of patients was 84 years, with a Logistic EuroSCORE of 23.5 percent.

One hundred percent of patients experienced mild or less aortic regurgitation at six months, with 74 percent of patients experiencing none/trace aortic regurgitation. The mean gradient (mmHg) pre-procedure to discharge as measured by transthoracic echo improved from 47.1 mmHg to 13.8 mmHg, and sustained these results at six months (13.7 mmHg). The hemodynamic outcomes were assessed and reported by an independent imaging core laboratory.

Secondary endpoints (VARC defined Safety) had a combined Safety Rate of 89 and 85 percent, respectively, at 30 days and six months. Within 30 days, there were two strokes and one patient experienced a myocardial infarction (MI); however, there were no additional strokes or MIs after 30 days. There was only one major vascular complication in the 54 patient cohort. The VARC Combined Device Success was 96.3 percent. No patient required rapid pacing or post-dilatation, minimizing the risk of hemodynamic stress for patients.

Physician comments

“The Direct Flow Medical system is demonstrating very low mortality, sustained improvement in hemodynamics and minimal aortic regurgitation at six months,” said Dr. Latib. “It is also continuing to demonstrate excellent results in a larger patient cohort. The system enables us to optimize outcomes for our patients by allowing full hemodynamic assessment and the flexibility of repeated repositioning, as well as retrieval, improving the TAVR procedure and minimizing risk.”

Regulatory status

The Direct Flow Medical system received the CE Mark in January 2013 and is currently available commercially in Europe. It has not been approved for use in the USA, Canada, or Japan.

Source: Direct Flow Medical, Inc., Business Wire