Hemodynamic effects of isoproterenol infusion in patients with normal and diseased mitral valves.

Twenty-six adult patients were studied by coimbined right and left heart catheterization to define or further to quantitate valvular defects suspected on clinical grounds. Right heart catheterization was accomplished in the usual fashion from an antecubital vein and the left heart was studied by combined transseptal left atrial and retrograde left ventricular catheterization.4 By use of these methods the presence or absence of a diastolic gradient across the mitral valve could be determined from the simultaneous left atrial and left ventricular pressure pulses. To determine the presence of mitral insufficiency, 1.5 ml. of a 500 mig. per cent solution of indocyanine dye was injected into the left ventricle while blood was being continuously drawn from the left atrium through a densitometerl coupled to a photographic recordert A deflection that occurred within 6 seconds of injection was considered evidence of mitral