The Pathophysiology of Orthostatic Hypotension

The Pathophysiology of Orthostatic Hypotension

The purpose of this study is to determine the cause of low blood pressure in selective patients who have problems with their involuntary (autonomic) nervous system. These patients frequently have had symptoms throughout their life, and their disorder might have a genetic basis. The biochemical, physiological and pharmacological procedures in this study should help us define the problem and perhaps lead to more effective treatment.

Inclusion Criteria:

• severe orthostatic hypotension and other autonomic symptoms but do not meet criteria for standard diagnosis
• non-smokers
• drug-free
• able to give informed consent
• free of pulmonary, renal, hematopoietic, hepatic and cardiac disease

Exclusion Criteria:

• medications affecting the autonomic nervous system
• any chronic illness
• anemia (Hct<30)
• women of childbearing age who are pregnant or nursing
• smokers