Evaluate Effect of Optison on Pulmonary Artery Systolic Pressure (PASP) and Pulmonary Vascular Resistance (PVR).

A Phase 4, Placebo Controlled, Single-blind, Cross-over Safety Study to Evaluate the Effect of Optison on Pulmonary Artery Systolic Pressure (PASP) and Pulmonary Vascular Resistance (PVR) as Measured by Right Heart Catheterization

The design of this study is to conduct a comprehensive safety evaluation of the pulmonary hemodynamic effects of Optison. The study is being conducted in subjects referred for cardiac catheterization for clinical reasons.

Inclusion Criteria:

• Must be already scheduled for left and/or right heart catheterization for clinical reasons.
• Must be in sinus rhythm, without an arrhythmia likely to affect the ability to assess pulmonary hemodynamics by catheterization, as determined by the investigator.
• Women of childbearing potential must be using adequate birth control and have a negative pregnancy test.

Exclusion Criteria:

• History of right-to-left, bi-directional, or transient right-to-left cardiac shunts or diagnosed by color flow Doppler echocardiography during screening.
• Hypersensitivity to Optison, perflutren, blood, blood products, or albumin.
• Female subjects who are nursing mothers.