VENTRICULAR-TACHYCARDIA AND MYOCARDIAL DYSFUNCTION IN A HORSE

Ventricular tachycardia develops less frequently than supraventricular dysrhythmias and generally is more indicative of cardiac disease. The horse in this report had clinical signs of lethargy and hypophagia an d was determined to have sustained ventricular tachycardia. Echocardio graphy was a valuable diagnostic tool and revealed an echodense area i n the left ventricle that had subnormal ventricular performance. A pri mary heart problem of an inflammatory nature was suspected. The horse responded favorably to treatment with lidocaine, antimicrobials, and a spirin, as well as stall rest. The horse was used successfully as a si re and hunter-jumper after treatment, but subsequently died 2.2 years later of massive hemoperitoneum. Necropsy revealed an extensive area i n the left ventricle that appeared thin and fibrotic.