212
Participants
Start Date
March 1, 2022
Primary Completion Date
April 30, 2023
Study Completion Date
May 30, 2024
Valsalva assist device
A valsalva assist device designed to provide the recommended resistance to exhalation at a pressure of 40 mmHg.
standard Valsalva manoeuvre
The Valsalva manoeuvre is carried out without any device.
Capital Medical University affiliated Beijing Anzhen Hospital, Beijing
Beijing Anzhen Hospital
OTHER