Sudden death of a horse with supraventricular tachycardia following oral administration of flecainide acetate.
OBJECTIVE
To describe a case of supraventricular tachycardia and sudden death in a horse following administration of flecainide acetate.


METHODS
An 8-year-old Hanoverian warmblood gelding was treated for chronic, naturally occurring, supraventricular tachycardia with digoxin, procainamide hydrochloride, quinidine sulfate, and flecainide acetate. After oral administration of flecainide, polymorphic ventricular tachycardia (torsades de pointes) and ventricular fibrillation developed, leading to cardiovascular collapse and death.


CONCLUSIONS
Atrial fibrillation is the most commonly diagnosed dysrhythmia associated with poor performance in horses, while atrial tachycardia is rarely documented. Here, we describe a case of sudden death in a horse with atrial tachycardia following the oral administration of flecainide acetate, after the lack of response to other antiarrhythmic drugs. Information provided in this case report is new and will make clinicians aware of the potential complications of flecainide alone or in combination with other drugs, in horses with cardiac dysrhythmias.
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210.
Katarzyna A
KA
Dembek
Samuel D A
SD
Hurcombe
Karsten E
KE
Schober
Ramiro E
RE
Toribio
D000284:Administration, Oral; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage* / Q000009:adverse effects; D003645:Death, Sudden / Q000662:veterinary; D003937:Diagnosis, Differential; D005424:Flecainide / Q000008:administration & dosage* / Q000009:adverse effects; D006734:Horse Diseases / Q000175:diagnosis* / Q000188:drug therapy; D006736:Horses; D008297:Male; D013617:Tachycardia, Supraventricular / Q000188:drug therapy / Q000662:veterinary*
D000889:Anti-Arrhythmia Agents; D005424:Flecainide
arrhythmias; atrial fibrillation; atrial tachycardia; equine; flecainide