Effect of β-Blocking Therapy on Outcome in the Multicenter UnSustained Tachycardia Trial (MUSTT)

Abstract

Background-␤-Blockers are known to reduce total mortality and sudden death in survivors of recent myocardial infarction. The effects of these agents in patients at high risk for sudden death with remote infarction are not clear. Methods and Results-We analyzed the effect of ␤-blockers on outcomes in 2096 patients with coronary artery disease, ejection fraction Յ40%, and spontaneous nonsustained ventricular tachycardia enrolled in the Multicenter UnSustained Tachycardia Trial (MUSTT). Forty-five percent of 702 patients with inducible sustained ventricular tachyarrhythmia and 35% of 1394 patients without inducible tachycardia were discharged from hospital receiving ␤-blockers. Patients treated with ␤-blockers were younger and had higher ejection fractions, higher rates of recent angina, and more recent infarction. ␤-Blockers were associated with decreased total mortality for the entire study population (5-year mortality 50% with ␤-blockers versus 66% without ␤-blockers; adjusted Pϭ0.0001). The mortality benefit associated with ␤-blockers was present in patients with and without inducible tachycardia, except those treated with implantable defibrillators. There was no significant effect of ␤-blocker therapy on the rate of arrhythmic death or cardiac arrest (adjusted Pϭ0.2344). Conclusions-␤-Blocking agents have beneficial effects on survival of patients having characteristics of those enrolled in the MUSTT trial. These effects do not appear to be due to a specific antiarrhythmic effect of ␤-blockers. The beneficial effects of ␤-blockers were demonstrable in all patients except those treated with implantable defibrillators. (Circulation.

Factors Influencing Appropriate Firing of the Implanted Defibrillator for Ventricular Tachycardia/Fibrillation

“…In our study, there was no association of ICD therapy with QRS width, when the latter was examined as either a continuous or dichotomized (Ͼ120 ms) variable. Previous reports have shown that an elevated heart rate at baseline is associated with future occurrences of ventricular tachyarrhythmias (8) and that beta-blocker therapy is associated with a reduced recurrence of VT/VF and ICD shocks (9,10). In the current analysis, an inverse association between beta-blocker use and ICD therapy was observed, whereas an elevated heart rate was not predictive of ICD therapy and/or death.…”

ACC/AHA/ESC 2006 Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death

“…Beta blockers are safe and effective antiarrhythmic agents that can be considered the mainstay of antiarrhythmic drug therapy (242,243). The mechanism of antiarrhythmic efficacy of this class of drugs involves competitive adrenergic-receptor blockade of sympathetically mediated triggering mechanisms, slowing of the sinus rate, and possibly inhibition of excess calcium release by the ryanodine receptor (244).…”

Effect of Statin Therapy In Ventricular Arrhythmias In Patient With Acute Anterior Myocardial Infarction

“…10 Standard anti arrhythmic drugs fails to reduce, or even increases the incidence of sudden cardiac death due to severe side effects and potentially lethal proarrhythmia. 11 Statin are safe drugs with no proarrhythmic effect and can become a low risk preventive agent for ventricular arrhythmia.…”