[Right atrial ablation of ectopic atrial tachycardia using a 20-pole mapping catheter].
BACKGROUND
Ectopic atrial tachycardia (EAT) are frequently unresponsive to pharmacological antiarrhythmic therapy. Radiofrequency ablation seems to be a safe approach to treat those arrhythmias. In the present study we report our results of radiofrequency ablation of EAT with a new mapping system (Stablemapr, Medtronic).


METHODS
Thirty consecutive patients with right atrial tachycardia were included in the study. In 15 patients (G1) the 20-polar Stablemapr was used for localization of the arrhythmia foci. Data were compared with a control group (G2, n=15), in which mapping was performed conventionally. The demographic characteristics and the distribution of the different cardiac diseases were comparable in both groups. In group 1 the identification of the EAT was facilitated by the placement of the 20-pole mapping catheter in the right atrium. In group 2 point by point measurements were performed to find the earliest local atrial activation compared to a reference electrode in the high right atrium (activation mapping), or foci were identified by analysis of the P-wave morphology during stimulation (pacemapping).


RESULTS
It was possible to successfully ablate all atrial tachycardias. The distribution of the foci was similar in both groups (G1/G2): near to the superior (3/5) and inferior (1/0) caval vene ostium, on the free wall (3/3), at the coronary sinus ostium (3/3) and on the interatrial septum (5/4). The mean procedure (G1: 88+/-33 vs G2: 151+/-61 min; p= or <0.05) and fluoroscopic times (G1: 19+/-9 vs G2: 38+/-28 min; p= or <0.05) were significantly shorter in group 1. Moreover, the mean number of radiofrequency applications was reduced significantly by using the new mapping system (G1: 10+/-10 vs G2: 16+/-13; p= or <0.05).


CONCLUSIONS
Radiofrequency ablation of EAT with right atrial focus can be performed safely and successfully using a 20-pole mapping catheter. The greatest advantages compared to conventional mapping and ablation strategies lies in the shortened investigation and fluoroscopic time.
Schueller
P O
PO
Klinik für Kardiologie, Pneumologie und Angiologie, Medizinische Klinik und Poliklinik B der Heinrich-Heine-Universität Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany. schueller@med.uni-duesseldorf.de
Meyer
C
C
Dierkes
S
S
Perings
C
C
Hennersdorf
M G
MG
D018780:Body Surface Potential Mapping / Q000295:instrumentation / Q000379:methods*; D006328:Cardiac Catheterization / Q000295:instrumentation / Q000379:methods*; D017115:Catheter Ablation / Q000379:methods*; D006325:Heart Atria / Q000601:surgery; D006801:Humans; D008875:Middle Aged; D025321:Surgery, Computer-Assisted / Q000379:methods*; D013612:Tachycardia, Ectopic Atrial / Q000175:diagnosis* / Q000601:surgery*; D016896:Treatment Outcome