abstract:In 1897 Engelmann introduced four Greek terms to describe key physiological properties of the heart: inotropy; the ability to contract, chronotropy; the ability to initiate anelectrical impulse, dromotropy; the ability to conduct an electrical impulse, and bathmotropy; the ability to respond to direct mechanical stimulation. A fifth term, lusitropy, was introduced in 1982 when relaxation was recognized to be an active process, and not simply dissipationof the contractile event [2].