Testing Muscle and Movement Techniques to Improve Blood Pressure and Heart Function in Children and Teens Who Faint

What this Trial Is About

Researchers are investigating whether specific muscle movements in the lower body, called discrete counterpressure maneuvers CPM, can improve blood pressure and heart function in children aged 6 to 18 years who experience fainting. The study focuses on children with recurrent fainting due to vasovagal syncope or postural orthostatic tachycardia syndrome POTS. Researchers will compare cardiovascular responses to different maneuvers and analyze factors like sex, puberty stage, body size, and autonomic nervous system control. Participants will perform a series of movements including leg crossing with muscle tensing, crouching, exaggerated forward-backward swaying, and rhythmic gluteal muscle clenching. These maneuvers will be tested alongside a baseline standing period, with volunteers acting as their own controls. The study involves one 1.5-hour session where participants will undergo cardiovascular monitoring using non-invasive devices measuring heart rate, blood pressure, cerebral blood flow, and stroke volume. Tests include the Valsalva maneuver and sit-stand transitions. During the session, participants will complete questionnaires on fainting history, physical activity, and quality of life. Measurements of height, weight, muscle mass, and pubertal development will be taken. Urine samples will be collected briefly for sodium testing. Continuous cardiovascular data will be recorded during rest, standing, and maneuver performance. The main outcome is how stroke volume relates to postural movements. Safety will be monitored closely, and testing will pause if participants feel unwell. The total participation time is about 1.5 hours in a controlled clinical setting.

Postural Sway and Counterpressure Maneuvers for Pediatric Syncope