Pulmonary and left atrial hemodynamics in mital stenosis.

A laboratory model has been utilized to evaluate left atrial and pulmoanry hemodynamics while comparing atria of three different compliances, five valve orifices, four pulmonary complicances, two venous pressures, and a predetermined pulmonary vascular resistance. The data demonstrate significant relationships between these variables and cardiac output, pulmonary artery pressure, and left atrial pressure and between the variables themselves. The complexity of these interrelationships is consistent with the lack of simple linear relations between current clinical measurements and emphasizes the need for measurements of compliance if the hemodynamic consequences of mitral stenosis are to be better understood.