No abstract

Background-Atrial tachycardias (AT) often occur after ablation of long-lasting persistent AF (CAF) and are difficult to treat conservatively. This study evaluated mechanisms and success rates of conventional mapping and catheter ablation of recurrent ATs occurring late after stepwise ablation of CAF. Methods and Results-A total of 320 patients underwent de novo ablation of CAF using a stepwise ablation approach in 2006 to 2007 at our institution. This study comprised patients who presented with recurrent ATs at their first redo procedure after initial de novo CAF ablation. All procedures were guided by conventional mapping techniques exclusively. Sixty-one patients (63Ϯ10 years, 14 women) presented with their clinical AT at their redo procedure 7.7Ϯ4.4 months after initial de novo CAF ablation. A total of 133 ATs (2.2Ϯ0.9 per patient) were mapped. Forty-four (72%) were due to reentry; 17 (28%) were focal ATs. Reentry ATs were mainly characterized as roof and perimitral flutter (43% and 34%, respectively). Focal ATs mainly originated from the great thoracic veins (pulmonary veins: 41%, coronary sinus: 23%). Forty-five (74%) patients had conduction recovery of at least 1 pulmonary vein (mean, 1.2Ϯ0.8).Overall, 124 (93%) ATs could be ablated successfully. The mean procedure duration was 181Ϯ59 minutes, with a mean fluoroscopy time of 45Ϯ21 minutes. After a mean follow-up of 21Ϯ4 months, 50 (82%) patients were free of any arrhythmia recurrences after a single redo procedure. Conclusions-Although late recurrent ATs may have complex mechanisms, catheter ablation guided exclusively by conventional techniques is highly effective with excellent acute and long-term success rates. (Circ Arrhythm Electrophysiol. 2010;3:160-169.)

The TC-SF catheter does not provide sufficient feedback from the ablated tissue to prevent steam popping.

The present study indicates that the distinct surface ECG pattern in Danon disease is not associated with ventricular pre-excitation. Atrial fibrillation is frequently observed in these patients and may be associated with thromboembolic events in the young, while sustained ventricular arrhythmias occur less frequently than previously reported.

Background-Termination of persistent atrial fibrillation (AF) can be achieved through ablation, with the majority of patients terminating to an atrial tachycardia (AT) and fewer directly to sinus rhythm (SR). We aimed to identify potential predictors for the existence of a substrate for AT on termination to SR.