View clinical trials related to Postural Tachycardia Syndrome.
Filter by:Background: - The autonomic nervous system helps control things that happen automatically in the body, like blood pressure, heart rate, and digestion. When it doesn t work properly, it s called dysautonomia. Researchers want to learn more about dysautonomias and train doctors to learn how to better diagnose them. Objectives: - To allow people with autonomic disorders to be evaluated. - To help fellows in the NIH Autonomic Disorders fellowship program see a variety of diseases in their training. Eligibility: - People age 18 and older with dysautonomia; children over age 2 if they might benefit - Healthy adult volunteers Design: - Participants will have different procedures depending on their symptoms. They will have one or more visits. They will have some but not all of the tests below. - Participants will have a medical history and physical exam. They may be tested for problems thinking. They may complete a symptom questionnaire. They may have their temperature and blood pressure taken. - Participants may have an intravenous line placed. A needle will guide a thin plastic tube into an arm vein. - Participants may have blood drawn several times. They may give a urine sample. - Participants may have an electrocardiogram. - How much blood a participant s heart is pumping and/or how much blood is flowing through their arm may be measured. The total amount of blood in their bloodstream may be measured. - Participants may have their ability to sweat and/or sense of smell tested. - Breathing, bowel sounds, and/or body functions may be monitored. - Pupil size, response to environmental temperature changes, and/or breathing may be measured. - Participants may have a bladder ultrasound. - Small pieces of skin may be taken for study.
One goal of this study is to determine whether people with different amounts of dopamine-beta-hydroxylase (DBH) have different responses to events that affect blood pressure and heart rate. We will also study whether increasing dietary salt improves symptoms during upright posture. Finally, we will examine whether the dietary sodium level influences serum DBH activity and whether DBH level influences the response to sodium. DBH levels and the function of the sympathetic or involuntary nervous system will be assessed in normal volunteers and in patients with postural tachycardia syndrome (POTS).