Pimobendan is a cardiotonic agent. The study of the cardiotonic mechanism of pimobendan using ventricular muscles from rabbits and guinea pigs suggests that Pimobendan acts by inhibiting phosphodiesterase III and potassium channel. The potent venodilating action of pimobendan makes it a suitable treatment option for patients with congestive heart failure (CHF) as it also improves systemic vasoconstriction
Pimobendan is mainly used in the management of heart failure in dogs, most commonly caused by myxomatous  mitral valve desease (also previously known as endocardiosis), ordilated cardiomyopathy.