ENDOCARDIAL ACTIVATION MAPPING OF VENTRICULAR-TACHYCARDIA IN PATIENTS- FIRST APPLICATION OF A 32-SITE BIPOLAR MAPPING ELECTRODE CATHETER

Background-Localization of early activated endocardial areas during ve ntricular tachycardia (VT) is mandatory for performance of surgical or radiofrequency catheter interventions. The use of a multielectrode ca theter may shorten the procedure time and increase the accuracy of the procedure compared with single-electrode mapping techniques. This stu dy was performed to evaluate the safety and efficacy of a 32-bipolar-e lectrode mapping catheter in patients. Methods and Results-The basket- shaped mapping catheter (BMC), integrated with a computerized mapping system, allowed on-line reconstruction of endocardial activation maps. Twenty patients with VT were studied before surgery (n=4) or radiofre quency catheter ablation (n=16). End-diastolic left ventricular (LV) v olume was 280+/-120 mL, with an LV ejection fraction of 33+/-14%. The volume encompassed by the BMC was 164+/-27 mL (130 to 200 mt); the dep loyment time was 46+/-11 minutes. Endocardial activation time during s inus rhythm was 105+/-34 ms: 14+/-5 electrodes could be used to stimul ate the heart. Cycle length of VT was 325+/-83 ms. Earliest endocardia l activation was recorded 58+/-42 ms before the onset of the surface E CG. Complications were pericardial effusion (n=2) and transient cerebr al disorientation (n=1), Conclusions-Percutaneous multielectrode endoc ardial mapping in patients with VT is feasible and relatively safe. Th e use of this technique shortens the time patients have to endure VT.