Author + information
- Koji Ikeda, PhD,
- Mami Ho, MD, PhD and
- Masayuki Kawahara, MD⁎ ()
- ↵⁎Office of Medical Devices, Pharmaceutical and Medical Devices Agency, Shin-kasumigaseki Building, 3-3-2, Kasumigaseki, Chiyoda-ku, Tokyo, Japan
First, we sincerely express our appreciation for the organized effort by the Valve Academic Research Consortium (VARC) members (1). Similar to the United States, there is no approved transcatheter aortic valve implantation (TAVI) device in Japan at present. We believe that this VARC consensus report is beneficial, even for the Pharmaceutical and Medical Devices Agency (PMDA), which is the regulatory authority in Japan.
Although we believe that the consensus is already well organized, we comment here on several points from the PMDA perspective.
1. The definition of intended performance of the prosthetic heart valve. Considering implantation in smaller body size, such as in Asian patients, or future possible expansion of the size variation of TAVI device, the critical value of 1.2 cm2 for the aortic valve area may need some adjustment based on patient body size or device size.
2. Hospitalization criteria variance among countries. We bring to your attention that there will be a possible bias by each country's medical care setting. For example, the threshold of hospitalization would be lower in Japan than in United States or the European Union.
3. Evaluation of stroke. The consensus proposed the modified Rankin Scale (mRS) score at 30 and 90 days for the stroke definition. We suggest that National Institutes of Health Stroke Scale (NIHSS) should also be used, and the time point of the evaluations should cover event onset (acute phase) as well, first, because generally the mRS score would be appropriate for the relatively chronic phase and NIHSS would be more appropriate for the acute phase and, second, because immediate treatment of stroke will greatly influence the mRS score at 30 and 90 days, and its evaluation would not properly reflect the impact as a TAVI complication. In addition, the NIHSS was proposed in U.S. Food and Drug Administration guidelines (2) in 2007 for a neurothrombectomy device and used in many clinical studies for cerebrovascular disorders.
We hope that our comments contribute to honing the criteria consensus further.
- American College of Cardiology Foundation
- Leon M.B.,
- Piazza N.,
- Nikolsky E.,
- et al.