Dynamic Assessment of Right Ventricular Function With Inhaled Nitric Oxide During Cardiac MRI

Dynamic Assessment of Right Ventricular Function With Inhaled Nitric Oxide During Cardiac MRI

The purpose of the study is to measure RV ejection fraction (RVEF), pulmonary flow, and pulmonary perfusion before and after exposure to inhaled nitric oxide in patients with pulmonary arterial hypertension (PAH) who are known to be vasodilator-responsive based on invasive catheterization as well as healthy subjects. Measurements will also be made after high flow oxygen alone to test the relative vasodilatory effect of oxygen and NO. The investigators hypothesize is that inhaled nitric oxide during cardiac MRI can be used to measure dynamic changes in RV-pulmonary vascular function in patients with vasodilator-responsive PAH.

Inclusion Criteria:

• Patients age 18 or older of the Vanderbilt Center for Pulmonary Vascular Disease. Vasodilator-responsive patients will be identified based on prior response to inhaled nitric oxide during invasive right heart catheterization
• Healthy subjects age 18 or older not known to have cardiopulmonary disease

Exclusion Criteria:

• Standard conventional contraindications for cardiac magnetic resonance (CMR) imaging
• Allergy or contraindication to Magnevist (gadopentetate dimeglumine) contrast
• Concurrent intravenous epoprostenol infusion in whom performance of CMR is cumbersome
• Pregnant women