Cardioversion for Atrial Fibrillation: Treatment Options and Advances

Abstract

Atrial fibrillation (AF) is associated with significant morbidity and mortality. There are two basic approaches to managing AF: slowing the ventricular rate, while allowing the arrhythmia to continue (the rate-control approach), and restoring and maintaining sinus rhythm (the rhythm-control approach) with antiarrhythmic drugs (AADs) and/or ablation, electrical cardioversion (CV), if needed, or both. Strategy trials comparing rate and rhythm control have found no survival advantage of one approach over the other, but other considerations, such as symptom reduction, often necessitate pursuit of rhythm control. Electrical, or direct current, CV is a widely used and effective method for termination of nonparoxysmal AF, although its success can be affected by patient- and technique-related variables. Pharmacological CV options also exist and are preferable in specific circumstances. Both pharmacological and electrical CV are associated with the risk of proarrhythmia. Many AADs are under development for both CV and maintenance of sinus rhythm. Some are atrioselective, such as vernakalant, and target ion channels in the atria, with little or no effects in the ventricle. Vernakalant, currently under Food and Drug Administration review, appears to offer a safer profile than current CV agents and is likely to expand the role of pharmacological CV. Other new AADs that provide increased efficacy or safety while maintaining normal sinus rhythm may also be better than current drugs; if so, rate-rhythm comparisons will differ from those of previous studies. In conclusion, further trials should clarify the long-term safety profiles of new atrioselective agents and other investigational drugs and define their role in the treatment of AF.

Use of rate control medication before cardioversion of recent-onset atrial fibrillation or flutter in the emergency department is associated with reduced success rates

“…Identifying which aspects of management influence successful cardioversion could lead to widespread uptake of those practices and abandonment of those that do not. Known patient factors associated with successful cardioversion include patient factors such as weight, 6 duration of arrhythmia, 7 and a history of hypertension. 6 Treatment factors include those affecting skin impedance, electrode placement, biphasic versus monophasic waveform, and initial and total energy.…”

Pharmacologic Atrial Defibrillation by Drug Delivery Into the Temporarily Occluded Coronary Sinus

“…6) Current therapies include antiarrhythmic drugs, electrical devices (pacemakers, defibrillators), and radiofrequency catheter ablation, all of which remain unsatisfactory for long-term management. 7) Of the more "unconventional" strategies for AF control, the pharmacological atrial defibrillator might prove to be particularly useful. Lurie, et al reported that significantly higher femoral vein and coronary sinus procainamide levels can be achieved by RA compared to peripheral venous drug infusion, 2) and the development of a device that delivers antiarrhythmic drugs into the right atrium or the superior vena cava has been reported.…”

Strategia utrzymania rytmu zatokowego u pacjentów z niezastawkowym migotaniem przedsionków — stan wiedzy, kontrowersje, toczące się badania

“…Zabieg wykonuje się w krótkotrwałym znieczuleniu ogólnym. W obowiązujących wytycznych nie sprecyzowano, jakiej energii impulsu należy użyć, ale podkreśla się większą skuteczność prądu dwufazowego z początkową energią impulsu 150-200 J, z ewentualnym stopniowym zwiększaniem energii w kolejnych próbach [23]. Dowiedziono, że generatory dwufazowe są skuteczniejsze i wywołują mniejsze uszkodzenie miokardium [24].…”