PO-04-089 AN UNUSUAL CASE OF A RIGHT ATRIAL APPENDAGE TO POSTERIOR RIGHT VENTRICULAR OUTFLOW TRACT ACCESSORY PATHWAY

Non-annular accessory pathways are rare to encounter in clinical practice. We present a case of right atrial appendage posterior ventricular outflow tract pathway patient with Wolf-Parkinson-White Syndrome. N/A A 26-year-old male structurally normal heart and syndrome was referred our lab for electrophysiology study catheter ablation. He had two prior studies one unsuccessful ablation attempt what thought be an anteroseptal pathway. Baseline delta wave inferior axis negative lead V1 (Figure 1A). Orthodromic atrioventricular re-entrant tachycardia easily induced occurred spontaneously during the procedure. Activation mapping sinus rhythm showed earliest activation 1F) distant from tricuspid annulus. Limited performed at this site did not alter conduction. Intracardiac echocardiographic imaging 1B) revealed closest tissue appendage. With pacing, 1D) distance 25.5 mm signal 1E). The signals were fused 1D). radiofrequency using 25 W initially up-titrated 40 W, pre-excitation eliminated. local EGM initial separated. After waiting period greater than 30 minutes no further observed. There VA conduction after elimination. Adenosine given resulted complete AV block. Final ECG 1C). At month follow up he recurrence palpitations or tachycardia. Of limited reports on ventricle hearts, most failed attempts. suspect is likely due under recognition non-annular pathways.