Effect of dofetilide in patients with recent myocardial infarction and left-ventricular dysfunction: a randomised...

Area of Science:

• Cardiology
• Pharmacology

Background:

• Arrhythmias post-myocardial infarction (MI) contribute significantly to mortality.
• Previous antiarrhythmic drug trials have shown limited efficacy.
• Dofetilide, a novel Class III antiarrhythmic agent, was evaluated in post-MI patients with left-ventricular dysfunction.

Purpose of the Study:

• To investigate the effect of dofetilide on all-cause mortality and morbidity in patients with left-ventricular dysfunction following MI.
• To assess the efficacy of dofetilide in reducing cardiac and arrhythmic mortality.

Main Methods:

• A randomized, double-blind, placebo-controlled trial involving 1510 patients with severe left-ventricular dysfunction (ejection fraction ≤ 0.35) across 37 Danish coronary-care units.
• Patients were assigned to receive either dofetilide (n=749) or placebo (n=761).
• Primary endpoint was all-cause mortality; secondary endpoints included cardiac and arrhythmic mortality.

Main Results:

• No significant difference in all-cause mortality (31% vs 32%), cardiac mortality (26% vs 28%), or total arrhythmic deaths (17% vs 18%) between dofetilide and placebo groups.
• Dofetilide demonstrated significant efficacy in restoring sinus rhythm in patients with atrial fibrillation or flutter (25/59 vs 7/56; p=0.002).
• Seven cases of torsade de pointes ventricular tachycardia occurred, all in the dofetilide group.

Conclusions:

• Dofetilide treatment did not impact all-cause mortality, cardiac mortality, or arrhythmic deaths in patients with severe left-ventricular dysfunction post-MI.
• Dofetilide proved effective for treating atrial fibrillation or flutter in this specific patient population.
• The study highlights a potential role for dofetilide in rhythm control for certain arrhythmias despite a lack of mortality benefit in this high-risk group.