Autonomic Determinants of POTS - Pilot1

• Status: Recruiting
• Trial end date: 2025-12-31
• Target enrollment: 0
• Participant gender: Female

Summary

Postural tachycardia syndrome (POTS) is a relatively common condition affecting mostly otherwise healthy young women. It is the cause of significant disability and an impairment in quality of life. These patients have high heart rate and symptoms during standing. Many of these patients are disabled and have a poor quality of life. The sympathetic nerves are part of the nervous system that helps to maintain normal blood pressures and heart rates during activities of daily life. The purpose of this study is to determine the importance of sympathetic activation as a cause of orthostatic symptoms. The investigators will assess the effects of a blood pressure medication (Moxonidine) on the symptoms during standing. Moxonidine lowers sympathetic activity. The investigators believe patients with high resting sympathetic activity might benefit from Moxonidine. It might reduce high heart rate and improve symptoms during standing. This study should help clinicians and the growing population of patients with POTS gain a better understanding of this disorder and find more personalized treatment.

• Phase: Early Phase 1
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: Vanderbilt University Medical Center
• Collaborator: National Heart, Lung, and Blood Institute (NHLBI)
• Treatments: Moxonidine

Criteria

Inclusion Criteria:

• female/male subjects, age 18-55 years,

• criteria for postural tachycardia syndrome (POTS):

1. a heart rate increase of ≥30 beats/min within 10 minutes of upright posture;

2. lack of orthostatic hypotension (blood pressure fall ≥ 20/10 mmHg within 10 minutes of standing); and

3. chronic symptoms during upright posture over at least 6 months, in the absence of any other acute cause.

• in the follicular phase of the menstrual cycle (day 5-13 of a 28-day cycle)

• POTS with primary central sympathetic activation (psPOTS) as defined as having resting muscle sympathetic nerve activity (MSNA) greater than or equal to 25 bursts/min

• able and willing to provide informed consent.

Exclusion Criteria:

• pregnancy,

• smoker,

• BMI>30 kg/m2,

• deconditioned status (if available VO2max<80% of predicted)

• unable to withdraw from medications known to affect autonomic function, blood pressure or blood volume

• systemic illnesses known to produce autonomic neuropathy, including but not limited to diabetes mellitus, amyloidosis, monoclonal gammopathies, and autoimmune neuropathies.

• Arteriosclerotic disease of carotid artery. History of neck surgery.

• conditions associated with inflammatory processes, such as coronary artery disease, hypertension, smoking, hypercholesterolemia (or on statin therapy), rheumatoid arthritis, diabetes

• treatment with oral corticosteroids, current infections (e.g., urinary tract infection), or use of non-steroidal anti-inflammatory drugs

• other factors which in the investigator's opinion would prevent the subject from completing the protocol including clinically significant abnormalities in clinical, mental or laboratory testing.