Rationale for the use of drugs in the treatment of cardiovascular disease 4. Antiarrhythmic drugs

CARDIAC arrhythmias are commonly discovered in veterinary patients. These animals may be suffering from cardiac disease, non-cardiac disease or may be apparently normal. Arrhythmias often result in a clinical quandary and many hours may be spent pondering the need for treatment and, if treatment is deemed necessary, the most effective therapy. This article outlines why some cardiac arrhythmias are of concern (and others are of no concern) and makes recommendations for the pharmacological management of some of the more common rhythm disturbances. This is a highly controversial topic and one in which facts are as sparse as opinions are common. The use of diuretics, vasodilators and positive inotropes in the treatment of heart failure patients was discussed in earlier articles (Boswood 1996, 1998, 1999).