Report Published on First-in-Human Use of Medtronic's CoreValve Evolut R TAVR System

December 13, 2013—In EuroIntervention, the report on the first-in-human use of the CoreValve Evolut R with EnVeo R delivery catheter (Medtronic, Inc., Minneapolis, MN) was published by Nicolo Piazza, MD, et al of McGill University Health Center in Montreal, Canada.

According to Dr. Piazza et al, the CoreValve Evolut R system is a novel transcatheter heart valve system with enhanced features that have the potential to improve the safety of transcatheter aortic valve replacement (TAVR). The newly designed EnVeo R delivery catheter is 14-F–equivalent and thus expands the option of transfemoral TAVR to a greater proportion of patients. Additionally, the EnVeo R delivery catheter allows the valve to be recaptured and repositioned during deployment, minimizing the consequences of valve malposition.

Dr. Piazza et al noted that the nitinol frame of the CoreValve Evolut R has been redesigned for superior interaction, consistent radial force, optimized cover index across the sizing range, and conformability with the native annulus, thereby hypothetically reducing stress on the left bundle branch. Large series with long-term follow-up are required to demonstrate the safety and efficacy of this device, advised Dr. Piazza et al.

As summarized and illustrated in EuroIntervention, the first-in-human procedure with the 23-mm CoreValve Evolut R system was conducted at the McGill University Health Center in September 2013. The patient was a 70-year-old woman with progressive dyspnoea (NYHA III) due to severely stenotic degenerated aortic bioprosthetic valve (mean gradient, 41 mm Hg; effective orifice area, 0.61 cm²). The heart team considered her too high risk for redo aortic valve surgery because she had previously undergone two coronary artery bypass surgeries and had multiple comorbid medical conditions (Society of Thoracic Surgeons mortality risk score, 7.9%). The degenerated aortic bioprosthesis (19-mm Carpentier Edwards Perimount Magna Ease [Edwards Lifesciences Corporation, Irvine, CA]) had an internal stent diameter of 16.5 mm on multislice CT.

According to Dr. Piazza et al, the 23-mm Evolut R is suitable for native annuli between 18 and 20 mm in diameter; however, smaller-diameter degenerated surgical bioprostheses have been successfully treated. The CoreValve Evolut R was successfully implanted via the right femoral artery using the EnVeo R delivery catheter and InLine sheath. In this case, it was not necessary to recapture the Evolut R during deployment.

Dr. Piazza et al reported that after implantation, the peak-to-peak and mean transaortic valve gradients were gratifyingly low: 6 mm Hg by invasive pressure recording and 8 mm Hg by echocardiography, respectively. It is likely that the supra-annular position of the CoreValve Evolut R leaflets accounted for this low postprocedural gradient. There was no central or paravalvular aortic regurgitation.

The low-profile CoreValve Evolut R system will extend the possibility of transfemoral TAVR to more patients; and coupled with the ability to recapture and reposition the valve, the CoreValve Evolut R has the potential to improve the accuracy and safety of TAVR procedures, concluded the report in EuroIntervention.

On October 22, 2013, Medtronic announced the initiation of the CoreValve Evolut R clinical study, which will enroll up to 60 patients with severe symptomatic aortic stenosis who are considered at high risk for surgical aortic valve replacement to evaluate the safety and effectiveness of the recapturable CoreValve Evolut R TAVR system.