Exercise training versus propranolol in the treatment of the postural orthostatic tachycardia syndrome.
This study consisted of a double blind placebo controlled trial of propranolol vs. placebo for 4 weeks followed by 3 months of exercise. Two hours standing studies were performed to assess physiology. The results were as follows:
- Both propranolol and exercise decreased standing heart rate.
- Propranolol decreased standing cardiac output while exercise training did not.
- Plasma catecholamines were unchanged with both exercise and propranolol.
- Aldosterone:renin ratio was increased with exercise but unchanged with propranolol.
- Quality of life (measured with the 36-item Short-Form Health Survey) was improved with exercise but not with propranolol.