Radiofrequency ablation of atrial arrhythmias after previous open-heart surgery.

AIM: To report the results of ablation of atrial arrhythmias (AA) after previous open-heart surgery.

METHODS

Nineteen patients [50+/-11 years, 11 women] underwent ablation of symptomatic AAs after previous open-heart surgery. In 11 patients mapping was performed using conventional multielectrode catheters. In the other eight patients CARTO electro-anatomical mapping system was used to supplement conventional mapping.

RESULTS

After conventional mapping, 10/11 patients (91%) were found to have typical atrial flutter (AFL). The cavotricuspid isthmus was successfully ablated in these 10 patients. CARTO combined with conventional mapping showed that 7 of 8 patients had one macro-reentry right atrial circuit. The remaining patient had two focal atrial tachycardias. CARTO-guided ablation was successful in all eight patients (100%). After follow-up of 12+/-11 months, 2/18 patients (11%) had recurrence of either the same (n=1) or a new (n=1) AA.

CONCLUSIONS

AAs after previous open-heart surgery can be ablated successfully (>90%) with a low recurrence rate (11%) at 1-year follow-up. Typical AFL was found frequently (14/19 patients, 72%). This could be ablated successfully, often, after conventional mapping alone. CARTO helps to uncover peri-scar reentry and guide the ablation by creating a line of block connecting the scar to another landmark (unconventional isthmus).