Evaluation of a method to correct the contractility index LVdP/dt(max) for changes in heart rate.

Introduction: In order to differentiate heart rate (HR)-induced changes from drug-induced positive or negative inotropic effects, HR-dependent effects need to be taken into account. Left ventricular (LV)dP/dt(max), the maximal value of the first derivative of a left ventricular pressure signal, is a convenient index for LV contractile state. The objective of this study was to define the normal relationship between left ventricular LVdP/dt(max) and HR in chronically instrumented, conscious dogs, primates and minipigs in our laboratory and then to use these data as the basis for developing a LVdP/dt(max)-HR-correction formula for each species.