The purpose of this study is to describe the mechanism of orthostatic intolerance, relying
on cardiovascular physiological studies. The syndrome is of undetermined etiology, but the
syndrome causes impairment of a number of young adults, females more than males, with
symptoms of tachycardia, fatigue, lightheadedness, palpitations, blurred vision, chest
discomfort, difficulty concentrating, and dizziness with the upright posture. It is believed
that many different pathophysiological processes can give rise to this disorder.
- Orthostatic intolerance
- Inability or unwillingness to give informed consent