ABSTRACT
In addition to Doppler echocardiography and cardiac magnetic resonance imaging (MRI), right heart catheterization is a complementary, but indispensable procedure for hemodynamic assessment and diagnosis of many cardiac diseases. Right heart catheterization provides data on the pressures and oxygen saturations in the right heart chambers and the pulmonary artery (PA), including PA occlusion pressure, or "wedge" pressure. Combined with data obtained during simultaneous left heart catheterization, cardiac output, pulmonary and systemic vascular resistances, and ejection fractions are calculated, and shunt detection and quantification in structural heart disease can be performed. From these measurements, information about preload, afterload, and contractility are derived. Hemodynamic responses to changes in loading conditions and/or to pharmacologic interventions are often noted for accurate evaluation of the physiology of a specific condition. In contrast to right heart catheterization's undisputed value as a diagnostic tool in the cardiac catheterization laboratory, the bedside use of a pulmonary artery catheter (PAC) in critically ill patients is controversial.
