Carsatrin (free base)

Carsatrin is a purinylpiperazine-derived cardiotonic and antiarrhythmic agent. It acts as a positive inotrope by increasing twitch tension and prolonging ventricular action potential duration, an effect blocked by tetrodotoxin but not by common adrenergic antagonists. This profile makes it a useful research tool for studying sodium channel-dependent cardiac excitation-contraction coupling in vitro.