New safety, durability data for percutaneous mitral-valve repair system

Washington, DC New safety and durability data for the percutaneous MitraClip system (Evalve), an experimental device being tested for the treatment of mitral regurgitation, suggest that the device yields lasting improvements in mitral regurgitation, with at least two-thirds of patients treated surviving out beyond one year, without needing mitral-valve surgery or developing worsening mitral regurgitation . Of the patients who ended up needing valve repair, there appeared to be no downsides to first having been treated with the device, investigators said.


The MitraClip [Source: Evalve]
Surgical options were preserved, the authors, led by Dr Ted Feldman (Evanston Hospital, IL), write in the August 18, 2009 issue of the Journal of the American College of Cardiology.
The new data come from 107 patients treated as part of the nonrandomized EVEREST 1 and 2 studies. Results for both studies have previously been reported by heartwire, but the current paper includes larger numbers and additional details and follow up. The device itself emulates the edge-to-edge repair technique pioneered surgically by Dr Ottavio Alfieri, in which the free edge of the anterior mitral valve leaflet is joined to the posterior leaflet, creating a point of permanent coaptation and a double orifice.

Durable effects on mitral regurgitation
In the current study, 10 out the 107 patients, or 9%, had a major adverse event during the follow-up period, including one non-procedure-related death. No clip embolizations occurred, although partial clip detachment occurred in 10 patients.
Overall procedural success was 74%, and 64% left hospital with a mitral-regurgitation grade of 1 or less, as opposed to grade 3 or 4 at study entry. Importantly, as Feldman emphasized to heartwire, all of the patients in this series were surgical candidates—a requirement of the study protocol—but all were older, with more comorbidities than patients typically treated surgically for mitral regurgitation, according to the Society of Thoracic Surgeons database.
In all, 32 patients needed mitral-valve surgery within 3.2 years of receiving the MitraClip. Of these procedures, 84% were successful. A full 66% of patients did not require surgery and maintained a mitral-regurgitation grade of less than 2 at 12 months, the primary efficacy end point of the study.
Investigators also highlighted the "steep learning curve" seen in the study, with the first 30 procedures taking over four hours, while the last 30 typically took under three hours.
slide logo above
The fact that there were no in cath lab deaths during this procedure in over 100 patients compared with, for example, stent therapy, shows that this is acceptable in terms of safety, all the more so given that this is a brand new intervention," Feldman told heartwire.
A randomized trial, comparing percutaneous mitral-valve repair with the MitraClip with surgical valve replacement or repair is ongoing; one year follow up will be completed in October, Feldman said.
The MitraClip received CE mark in Europe last year.