RT-129
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Beta-blocker therapy for
prevention of sudden death in patients with sustained ventricular tachyarrhythmias
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G. Steinbeck, E. Hoffmann, R.
Haberl.
Klinikum Großhadern, Medizinische Klinik und Poliklinik I, Munich, Germany
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Abstract
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Reviewing the literature about the efficacy of
beta-blocker treatment in patients with a history of sustained ventricular tachycardia
and/or ventricular fibrillation, the most consistent finding is the negligible risk of
proarrhythmic effects. In fact, propranolol has been shown to suppress proarrhythmic
effects caused by class IC antiarrhythmic agents (Myeburg et al, 1989).
Next, beta-blockers are the first-line treatment for the idiopathic long QT-syndrome
(Moss et al, 1985) and furthermore have been found useful in very specialized cohorts of
patients, such as exercise-induced ventricular tachycardia without organic heart disease,
and ischaemia-induced ventricular tachycardia or ventricular fibrillation in case
revascularization either by PTCA or bypass-surgery is not feasible.
Finally, considering the vast majority of patients with recurrent sustained
ventricular tachycardia or cardiac arrest due to stable, but advanced coronary artery
disease, both uncontrolled clinical observations and a few, small prospective randomized
trials suggest only a modest potency of beta-blockers to prevent life-threatening
arrhythmia recurrences or sudden cardiac death. More information may in future be gained
from the CASH trial. While our present knowledge thus is limited, these authors believe
that beta-blocker therapy in general does not provide adequate protection from
life-threatening arrhythmic events, and that the true efficacy of stand-alone beta-blocker
therapy because of ethical concern may in future only be determined in patients in whom a
cardioverter-defibrillator has been implanted as a safeguard.
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Key Words
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Treatment of arrhythmias - pharmacological
management of malignant ventricular arrhythmias
sustained ventricular arrhythmias, sudden death, beta-blockers, propranolol, metoprolol,
CAST trial, CASH trial, R
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