Disopyramide (INN, trade names Norpace and Rythmodan) is an antiarrhythmic medication used in the treatment of ventricular tachycardia.
[6] However, a 2012 review of antiarrhythmic drugs noted that disopyramide is among the most toxic agents, with a high burden of side effects and increased mortality (compared to placebo) when used to treat atrial fibrillation.
[6] This effect is particularly well suited in the treatment of ventricular tachycardia as it slows the action potential propagation through the atria to the ventricles.
Disopyramide does not act as a blocking agent for beta or alpha adrenergic receptors, but does have a significant negative inotropic effect on the ventricular myocardium.
The most common variant of HCM presents with left ventricular (LV) intracavitary obstruction due to systolic anterior motion of the mitral valve, and mitral-septal contact, diagnosed readily with echocardiography.
Many investigators and clinicians believe that disopyramide controlled release is the most potent agent available for reducing resting pressure gradients and improving symptoms.
When used in patients resistant to beta-blockade, disopyramide is effective in 60% of cases, reducing symptoms and gradient to the extent that invasive procedures such as surgical septal myectomy are not required.
Teichman et al. showed that pyridostigmine used in combination with disopyramide substantially alleviates vagolytic side effects without compromising antiarrhythmic efficacy.
Using such a stepped strategy, investigators have reported that survival does not differ from that observed in the age-matched normal United States population.