title: Resolution of sustained narrow complex ventricular tachycardia and tachycardia-induced cardiomyopathy in a Quarter Horse following quinidine therapy.
abstract: Sustained narrow-QRS tachycardia of three months duration and left ventricular systolic dysfunction were identified in a fifteen-year-old Quarter Horse. No underlying cause for the tachyarrhythmia was found and no predisposing structural cardiac lesions were evident by echocardiography. Intravenous diltiazem and lidocaine were administered without achieving successful conversion of the arrhythmia. Oral quinidine therapy converted the tachyarrhythmia to sinus rhythm. Ventricular systolic dysfunction and chamber dilatation subsequently resolved. As with other species, echocardiographic features of dilated cardiomyopathy can be tachycardia-induced and may resolve following successful control of heart rate and rhythm.
authors: North Carolina State University, 1052 William Moore Drive, Raleigh, NC 27607, USA. jsterndvm@gmail.com
authors: Joshua A
authors: JA
authors: Stern
authors: Yamir R
authors: YR
authors: Doreste
authors: Susan
authors: S
authors: Barnett
authors: Sunshine M
authors: SM
authors: Lahmers
authors: Ryan D
authors: RD
authors: Baumwart
authors: Kathy K
authors: KK
authors: Seino
authors: John D
authors: JD
authors: Bonagura
mesh_terms: D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D006734:Horse Diseases / Q000188:drug therapy*; D006736:Horses; D008297:Male; D011802:Quinidine / Q000627:therapeutic use*; D017180:Tachycardia, Ventricular / Q000145:classification / Q000188:drug therapy / Q000662:veterinary*
chemical_list: D000889:Anti-Arrhythmia Agents; D011802:Quinidine