Moreover all the anti-arrhythmic agents that are used in treatment of AF were potentially pro-arrhythmic especially in patients with coronary artery disease and structurally abnormal heart .
Although atrial fibrillation ( AF ) is the most common sustained arrhythmia seen during daily cardiovascular physician practice , its management remained a challenge for cardiology physician as there was no single anti-arrhythmic agents proved to be effective in converting atrial fibrillation and kept its effectiveness in maintaining sinus rhythm over long term .
Some of these drugs also have serious non cardiac side effects that limit its long term use in the management of atrial fibrillation .
Several new and investigational anti-arrhythmic agents are emerging but data supporting their effectiveness and safety are still limited .
Effects of Digoxin on Acute, Atrial Fibrillation–Induced Changes in Atrial Refractoriness
Background Atrial fibrillation ( AF ) shortens the atrial effective refractory period ( ERP ) and predisposes to further episodes of AF . The acute changes in atrial refractoriness may be related to tachycardia-induced intracellular calcium overload . The purpose of this study was to determine whether digoxin , which increases intracellular calcium , potentiates the acute effects of AF on atrial refractoriness in humans . Methods and Results In 38 healthy adults , atrial ERP was measured at basic drive cycle lengths ( BDCLs ) of 350 and 500 ms after autonomic blockade . Nineteen patients had been treated with digoxin for 2 weeks . After a several-minute episode of AF , atrial ERP was measured serially at alternating BDCLs . Compared with pre-AF ERPs , the first post-AF ERPs were significantly shorter in both the digoxin and the control groups ( P < 0.001 ) . The post-AF ERP at a BDCL of 350 ms shortened to a greater degree in the digoxin group ( 37±16 ms ) than in the control group ( 20±13 ms , P < 0.001 ) ; similar changes occurred at a BDCL of 500 ms . During post-AF determinations of the atrial ERP , secondary AF episodes occurred significantly more often in the digoxin group ( 32 % versus 16%;P < 0.04 ) . Conclusions After a brief episode of AF , digoxin augments the shortening that occurs in atrial refractoriness and predisposes to the reinduction of AF . These effects occur in the setting of autonomic blockade and therefore are more likely to be due to the effects of digoxin on intracellular calcium than to its vagotonic effects
Moreover all the anti-arrhythmic agents that are used in treatment of AF were potentially pro-arrhythmic especially in patients with coronary artery disease and structurally abnormal heart .
Although atrial fibrillation ( AF ) is the most common sustained arrhythmia seen during daily cardiovascular physician practice , its management remained a challenge for cardiology physician as there was no single anti-arrhythmic agents proved to be effective in converting atrial fibrillation and kept its effectiveness in maintaining sinus rhythm over long term .
Some of these drugs also have serious non cardiac side effects that limit its long term use in the management of atrial fibrillation .
Several new and investigational anti-arrhythmic agents are emerging but data supporting their effectiveness and safety are still limited .