NONFLUOROSCOPIC ENDOCARDIAL CATHETER MAPPING OF ATRIAL-FIBRILLATION

Nonfluoroscopic Endocardial Catheter Mapping. The treatment of drug-re fractory atrial fibrillation (AF) remains one of the unsolved problems in cardiology. Surgical interventions have demonstrated that AF can b e prevented by multiple incisions within both atria. Recently, this st rategy has been translated into a catheter procedure. So far, the abla tion approach is not based on individual electrophysiologic data, but constitutes only an anatomic approach. Further insight into the spatia l and temporal distribution of the local electrograms during AF is nee ded. Electroanatomic maps acquired by sequential mapping over 45 secon ds at each site during AF in,six patients with paroxysmal AF were anal yzed off-line, Electrograms were sampled at a mean of 36 +/- 12 sites in the left atrium of each patient. A total of 217 sites were sampled, of which 27.3% (59) represented type A (regular) AF, 9.7% (21) repres ented type B (totally irregular), and 63.1% (137) represented type C ( mixture of type A and B) electrograms. The distribution was analyzed i n 20 different segments of the left atrium, and a significantly higher incidence of type A electrograms was found in area 3 (upper lateral p ulmonary vein) than at all other sites (P < 0.005). This observation n eeds further confirmation before any conclusion with regard to cathete r ablation can be drawn, particularly because the analysis was based o n bipolar recordings from a 4-mm tip electrode.