Clinical Trials

Have you been diagnosed with orthostatic intolerance? This study aims to find out how the body’s regulation of basic functions, such as heart rate and blood pressure, is altered in people who have orthostatic intolerance. This condition, which has an unknown cause, is characterized by a racing heartbeat, dizziness, lightheadedness, and other symptoms that occur when a person stands up. To participate in this study, you must be between 18 and 80 years old and have orthostatic intolerance. This study is located in Nashville, Tennessee.

The investigators will study the effect of pulmonary arterial vasodilation to see if it eliminates indices of persistent lung injury in smokers that are susceptible to emphysema.

This study will use dual energy x-ray computed tomography (DECT) to evaluate the relationship between heterogeneous perfusion, hypoxia (low oxygen in inspired gas) and induction of pulmonary vascular dilatation to characterize emphysema susceptibility in a normal smoking population.