3-DIMENSIONAL ENDOCARDIAL MAPPING SYSTEM USING A NOVEL X-RAY IMAGER AND LOCATING CATHETER

Percutaneous radiofrequency catheter ablation (RFCA) has a very high s uccess rate for certain arrhythmias, such as Wolff-Parkinson-White syn drome and idiopathic ventricular tachycardias in the right ventricular outflow tract. These arrhythmias are typically characterized by a sin gle site of arrhythmogenic tissue that is well bounded by anatomic mar kers. Success rates for RFCA for reentrant ventricular tachycardias, t achycardias not closely associated with anatomic markers, and those ha ving larger tissue areas requiring multiple overlapping lesions have b een significantly lower. An endocardial mapping system is being develo ped that includes a fluoroscopic imager that scans the field of view w ith a series of small x-ray beams and electrophysiology catheters modi fied to include miniature x-ray sensor elements. Preliminary work indi cates that the accuracy of determining the mapping catheter location r elative to the reference catheters will be +/-1.5 mm. Substituting a h ighly accurate three-dimensional coordinate system for anatomic marker s could improve the success rate of RFCA for complex arrhythmias.