What do we mean by ‘dextrocardia’?

Background: Atrial fibrillation is the most common sustained cardiac arrhythmia and has an important impact on costs of medical assistance. Traditional interventions to convert atrial fibrillation to sinus rhythm are antiarrhythmic drugs and external electrical cardioversion. However, the best option for starting the cardioversion is not well established. Methods: In a multicentre randomised trial of 139 patients with persistent atrial fibrillation lasting less than 6 months, we compared the effectiveness and the cost-effectiveness ratio of initial treatment with chemical or electrical cardioversion. Subjects who did not achieve sinus rhythm with chemical cardioversion were considered to undergo electrical cardioversion and vice-versa. Results: The efficacy of the initial attempt for cardioversion was similar with chemical or electrical cardioversion (74 vs. 73%, P=0.95). However, the strategy of starting with antiarrhythmic drugs was more effective than with electrical procedure (96 vs. 84%, P=0.0016). Initiating with chemical cardioversion was also less expensive than with electrical cardioversion (US$1240 vs. US$1917; P=0.002). Life-threatening complications occurred only during chemical cardioversion (5%), all of them in patients with structural heart disease. Conclusions: In patients with persistent atrial fibrillation of less than 6 months, initial chemical or electrical cardioversion appear to be similar but the strategy of starting the cardioversion with antiarrhythmic drugs is more effective and less expensive than starting with the electrical procedure. Patients with structural heart disease undergoing chemical cardioversion seem to be more susceptible to severe complications.