Left ventricular end-systolic pressure-volume relationships as a measure of ventricular performance.
The extent to which conclusions about myocardial performance may be drawn from end-systolic pressure-volume relations was investigated. Left ventricular isovolumetric and end-systolic pressure-volume relationships were measured in the rat, under acute impairment of contractility (hexobarbital), at chronic pressure overload (spontaneously hypertensive rats), and at chronic volume overload (aorto-caval shunt). Our results confirm the classic conception of Otto Frank where the curves of the isovolumetric maxima and the curves of the end-systolic pressure-volume relations follow separate courses. Acute alterations in contractility can be detected from shifts in the end-systolic pressure-volume relations. In chronic pressure or volume overloaded hearts the end-systolic pressure-volume relations do not render conclusions about ventricular or myocardial performance since in chronically altered hearts, the course of the end-systolic pressure-volume relations is primarily influenced by geometric factors.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002312:Cardiomyopathy, Hypertrophic / Q000503:physiopathology; D006324:Heart Arrest, Induced; D006439:Hemodynamics / Q000187:drug effects; D006591:Hexobarbital / Q000494:pharmacology; D009200:Myocardial Contraction / Q000187:drug effects*; D051381:Rats; D011918:Rats, Inbred SHR; D011919:Rats, Inbred Strains; D013318:Stroke Volume / Q000187:drug effects*; D013599:Systole / Q000187:drug effects; D016276:Ventricular Function
D006591:Hexobarbital