NCIt definition : A class Ia antiarrhythmic agent with cardiac depressant properties. Disopyramide phosphate
exerts its actions by blocking both sodium and potassium channels in cardiac membrane
during phase 0 of the action potential. This slows the impulse conduction through
the AV node and prolongs the duration of the action potential of normal cardiac cells
in atrial and ventricular tissues. Disopyramide prolongs the QT interval and causes
a widening of the QRS complex. It also possesses some anticholinergic and local anaesthetic
properties. Disopyramide phosphate is used in the treatment of supraventricular tachycardia.;