Three-dimensional endocardial mapping system using a novel x-ray imager and locating catheter

Percutaneous radiofrequency catheter ablation (RFCA) has a very high success rate for certain arrhythmias, such as Wolff-Parkinson-White syndrome and idiopathic ventricular tachycardias in the right ventricular outflow tract. These arrhythmias are typically characterized by a single site of arrhythmogenic tissue that is well bounded by anatomic markers. Success rates for RFCA for reentrant ventricular tachycardias, tachycardias not closely associated with anatomic markers, and those having larger tissue areas requiring multiple overlapping lesions have been significantly lower. An endocardial mapping system is being developed that includes a fluoroscopic imager that scans the field of view with a series of small x-ray beams and electrophysiology catheters modified to include miniature x-ray sensor elements. Preliminary work indicates that the accuracy of determining the mapping catheter location relative to the reference catheters will be +/- 1.5 mm. Substituting a highly accurate three-dimensional coordinate system for anatomic markers could improve the success rate of RFCA for complex arrhythmias.