“Lower Body Muscle Pre-activation in Initial Orthostatic Hypotension”
This study is aimed primarily at providing a simple and effective form of treatment to reduce the symptoms of Initial Orthostatic Hypotension (IOH) and prevent syncope. We will first characterize the physiology of IOH, and then we will study four sit-to-stand maneuvers, each with a different stress tests to identify the role of sympathetic activity vs. simple muscle contraction in IOH. Then we will complete an additional two sit-to-stands with interventions designed to decrease the blood pressure drop (and hopefully symptoms) with initial stand. These consist of physical counter maneuvers, which may be a possible treatment that can be used to mitigate the drop in blood pressure (BP) seen in IOH during a stand and relieve presyncope symptoms.
Physical counter-maneuver targeted at minimizing the large drop in BP seen in IOH patients.
Stress test involving submerging your hand in ice water or performing mental arithmetic to increase sympathetic activity.
Functional Electrical Stimulation
A mild electrical stimulus to passively induce a leg muscle contraction with minimal sympathetic activation.
Lower Body Muscle Pre-activation in Initial Orthostatic Hypotension: Effects on Orthostatic Tolerance