Predictors of conversion of atrial fibrillation after cardiac operation in the absence of class I or III antiarrhythmic medications.

BACKGROUND: Although risk factors for the development of atrial fibrillation (AF) after cardiac operations have been studied extensively, predictors of conversion to sinus rhythm within 24 hours of onset have not been examined. METHODS: Eleven hundred consecutive adults undergoing cardiovascular operations from July 1997 to June 1998 were screened for new onset AF after operation. Patients with chronic persistent preoperative AF or those who died within 48 hours of the operation were excluded. RESULTS: Three hundred fifty-three patients develop

Risk stratification for recurrent tachyarrhythmias in patients with paroxysmal atrial fibrillation and flutter: role of signal averaged electrocardiogram and echocardiography.

The value of signal-averaged P-wave electrocardiogram and echocardiography for predicting recurrent atrial tachyarrhythmias was prospectively investigated in 60 patients presenting with paroxysmal atrial fibrillation or flutter. All patients were followed up for 1 year after restoration of sinus rhythm. A stepwise discriminant function analysis was used to identify variables predicting recurrent atrial tachyarrhythmias. Analyzed variables included signal-averaged P-wave duration in 3 bipolar orthogonal leads (X,Y,Z) and their vector magnitude, as well as left and right atrial dimensions and volumes. During follow-up, 25 patients had recurrent atrial tachyarrhythmias, while 35 did not. Using discriminant function analysis, the left atrial antero-superior dimension was found to be the only variable predicting the recurrence of atrial tachyarrhythmias (p < 0.0038) and was able to correctly classify 65% of the study patients. It was concluded that, in patients with paroxysmal atrial fibrillation or flutter, the traditionally used determination of left atrial dimension was the variable most closely associated with a high risk for recurrent tachyarrhythmias. The signal-averaged P-wave duration did not improve tachyarrhythmia prediction.

Radiofrequency ablation for cardiac arrhythmias causing postcardiac injury syndrome.

We report 2 cases of exudative left pleural effusion following radiofrequency catheter ablation of cardiac arrhythmias complicated by cardiac perforation. We suggest that radiofrequency ablation may be a previously unsuspected cause of postcardiac injury syndrome.