[Computer analysis of ventricular pressure recordings: evaluation of myocardial contractility on the dog heart in situ].
The contractile indices Vmax (maximum shortening velocity of the contractile element) and ARPD (power averaged rate of power  density generation) which have been shown to be unaffected by alterations in preload and afterload were computed from isovolumic left ventricular pressure data of dogs. The two indices were tested for their ability to detect changes in contractility induced by a positive inotropic drug (Isoprenalin). Whereas a good correlation was found between ARPD and Vmax (coefficient of correlation 0,895) the index ARPD was more sensitive to augmentation of myocardial contractility; also because it is simpler to obtain computationally and more appropriate for the intact heart from a theoretical point of view. ARPD should be useful especially for quantification of acute changes in myocardial contractility.
D000703:Analog-Digital Conversion; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D003201:Computers; D004285:Dogs; D055590:Electromagnetic Phenomena; D006321:Heart / Q000502:physiology*; D007545:Isoproterenol / Q000494:pharmacology; D008954:Models, Biological; D009200:Myocardial Contraction / Q000187:drug effects; D012212:Rheology; D016276:Ventricular Function
D007545:Isoproterenol
Computeranalyse von Ventrikeldruckkurven: Bewertung der myokardialen Kontraktilität am Hundeherzen in situ