Chronic tocainide therapy for refractory high-grade ventricular arrhythmias.

Area of Science:

• Cardiology
• Pharmacology

Background:

• Complex ventricular ectopic activity and ventricular tachycardia are serious arrhythmias.
• Existing antiarrhythmic drugs have limitations in efficacy and safety for refractory cases.

Purpose of the Study:

• To evaluate tocainide, an oral analog of lidocaine, as a long-term antiarrhythmic agent.
• To assess the safety and efficacy of tocainide in patients with refractory symptomatic ventricular arrhythmias.

Main Methods:

• A study involving 21 patients with symptomatic complex ventricular ectopic activity.
• Patients received tocainide for 3 days to 35 months, with prior treatment failures.

Main Results:

• Tocainide was effective and safe in 14 out of 21 patients (66%).
• Lidocaine responsiveness predicted tocainide effectiveness.
• Minor CNS and GI side effects occurred but rarely precluded long-term use.

Conclusions:

• Tocainide is an effective and safe antiarrhythmic agent for refractory ventricular arrhythmias.
• Tolerable side effects and oral bioavailability support its use.
• Lidocaine responsiveness is a useful predictor of tocainide efficacy.