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: Joshua A Stern, Yamir R Doreste, Susan Barnett, Sunshine M Lahmers, Ryan D Baumwart, Kathy K Seino, John D Bonagura
• Journal: Journal of veterinary cardiology : the official journal of the European Society of Veterinary Cardiology (J Vet Cardiol) Vol. 14 Issue 3 Pg. 445-51 (Sep 2012) ISSN: 1875-0834 [Electronic] Netherlands
• PMID: 22841902 (Publication Type: Case Reports, Journal Article)
• Copyright: Published by Elsevier B.V.

Chemical References

• Anti-Arrhythmia Agents
• Quinidine

Topics

• Animals
• Anti-Arrhythmia Agents (therapeutic use)
• Horse Diseases (drug therapy)
• Horses
• Male
• Quinidine (therapeutic use)
• Tachycardia, Ventricular (classification, drug therapy, veterinary)