A supraventricular tachycardia with a possible accessory pathway in a young Labrador Retriever

A supraventricular tachycardia was diagnosed in a 3-year-old male Labrador Retriever. Based on patient signalment and characteristic electrocardiographic findings, an accessory pathway bypassing the normal atrioventricular nodal pathway causing an atrioventricular reciprocating tachycardia was a differential diagnosis. However, an alternative diagnosis of a focal atrial tachycardia was another possibility. The dog was successfully treated short-term with intravenous diltiazem, and long-term with modified release oral diltiazem. This report shows the utility of the electrocardiogram in the diagnosis of a supraventricular tachycardia, as well as the medical management for this emergency case.