Most cardiodynamic indices including positive and negative left ventricular (LV) dp/dt, and the ratio of either to left ventricular end diastolic pressure (LVEDP) as well as to each other, deviate in nearly identical fashion with both myocardial impairment and preejection ventricular unloading of the type seen in mitral insufficiency. Because peak contractile element velocity is an early preejection systolic event whereas preejection mitral insufficiency occurs later in this period, the rate at which ventricular pressure is developed in mitral insufficiency (MI) varies in an unique manner which frequently discriminates this condition from controls, primary ventricular dysfunction as seen in cardiomyopathy, and similar unloaded states such as aortic insufficiency.