Independent predictive factors of acute and first year success after electrical cardioversion in patients with chronic atrial fibrillation

Objectives. We retrospectively analyzed the predictive factors of successfu ly electrical cardioversion in patients with chronic atrial fibrillation. Methods. We included 118 patients, 68 men and 50 women, with a mean age of 65.1 years and a length of arrhythmia. evolution of 83.3 days. These patien ts consecutively underwent electrical cardioversion in our Cardiology Depar tment with a follow-up of one year to determine relapses. Structural cardio pathy was observed in 63.6% of the patients and 43.7% presented a left atri um between 4 and 5 cms. We analyzed the clinical and echocardiographic fact ors which predict the acute and first year success of electrical cardiovers ion. Results. The cardioversion was effective in 73.7% (Cl 95%, 64.6%-81.1%) of the patients and 35.6% (Cl 95%, 25.8%-46.6%) had a relapse within the first year. The inexistence of cardiomyopathy and therapy with amiodarone were p redictive of acute success (p < 0.04 and p < 0.03, respectively). The lengt h of arrhythmia. evolution did not predict acute success but did so when re lapses were analyzed. The size of the left atrium is predictive of both acu te and long term success (p < 0.02 and p < 0.001, respectively). Logistic r egression showed that the size of the left atrium and the patient's age wer e the only predictive factors of acute and first year success. Conclusions. Electrical cardioversion is very efficient in the short-term, despite numerous relapses. Patient age and the size of left atrium are asso ciated with acute and long-term success of cardioversion.