Pharmacological and electrical therapy of supraventricular tachyarrhythmias

This article reviews current pharmacological and electrical approaches to t he restoration of sinus rhythm in patients who suffer from atrial fibrillat ion and atrial flutter. Spontaneous conversion to sinus rhythm occurs in a high proportion of atrial fibrillation of < 24 h duration. Among patients p resenting with atrial fibrillation, which was clinically estimated to have lasted < 48 h, the likelihood of cardioversion-related clinical thromboembo lism is low, which supports the current practice of early cardioversion wit hout anticoagulation. Antiarrhythmic drugs effective in terminating atrial fibrillation of short duration are these which possess class IA, IC and III properties. Electrical transthoracic cardioversion by using different elec trode positions and additional pressure over the electrodes during shock de livery is a highly effective and well-tolerated method in restoration of si nus rhythm even in patients under conscious sedation. Immediate spontaneous reinitiation of atrial fibrillation can occur in a significant proportion of patients undergoing electrical cardioversion and can be reduced after a pretreatment with antiarrhythmic drugs. In patients with failed external ca rdioversion, internal low energy cardioversion offers an effective option f or restoring sinus rhythm. After cardioversion in a high proportion of pati ents antiarrhythmic drugs are necessary to prevent atrial fibrillation from recurring. A serial cardioversion approach can prevent the evolution of pe rmanent atrial fibrillation in a subgroup of patients. Over-drive atrial pa cing is an effective and minimally invasive procedure for termination of at rial flutter. The acute administration of class IA, IC and III antiarrhythm ic drugs increases the success rate of this method in restoring sinus rhyth m.