Cardiology
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A number of conventional and newer antiarrhythmic agents are available for the treatment and prophylaxis of ventricular tachycardia and sudden death. Using a multifaceted approach of programmed electrical stimulation studies, drug level determinations, exercise tolerance testing, and 24-hour ambulatory electrocardiographic monitoring, the physician can identify those patients who require therapy and then predict the likelihood of efficacy with each antiarrhythmic agent. ⋯ Serious adverse reactions necessitate a change in antiarrhythmic therapy, as opposed to lowering drug dosage to an ineffective level. The unacceptably high incidence of sudden death due to electrical instability can be reversed only by a rigorous and dedicated long-term approach to the management of serious ventricular arrhythmias.
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beta-Adrenergic blockade represents a major pharmacologic advance. These drugs bind to membrane adrenergic receptors interfering with the effects of endogenous catecholamines. ⋯ The drugs have varying pharmacodynamic properties that may modify certain side effects: beta 1-selectivity, partial agonism, alpha-adrenergic blocking activity, membrane stabilization, and varying pharmacokinetic characteristics. The drugs have been shown to be relatively safe and useful for a wide variety of cardiovascular and noncardiovascular disease states, and their wide spectrum of therapeutic activity illustrates the importance of the sympathetic nervous system in the pathophysiology of medical illness.