PO-672-06 SIMULTANEOUS HIS BUNDLE, LATERAL LV AND LATERAL RV PACING IN A PATIENT WITH REPAIRED TETRALOGY OF FALLOT

Patients with repaired Tetralogy of Fallot (ToF), who have RBBB and predominant right ventricular (RV) dysfunction may benefit from RV electromechanical resynchronization. We describe the case a patient ToF, biventricular (BiV) ineffective cardiac resynchronization therapy (CRT) in whom His bundle pacing (HBP) fused wall achieved CRT acute hemodynamic improvement. N/A 58 YOF ToF BiV presented decompensated heart failure (HF). implantable cardioverter-defibrillator (ICD) RA, coronary sinus (CS) leads (Biotronik, Berlin, Germany) was placed at an outside facility one year ago. Underlying EKG showed rhythm 1stdegree AVB (PR 240 ms), (QRSd 200ms) left posterior fascicular block. With presenting CRT, QRS wider 240). Chest Xray revealed ICD lead outflow tract (RVOT) CS anterior interventricular vein tip electrode also near RVOT. Given concern for suboptimal defibrillation vector limited alternative options, we pursued individualized optimization. Activation mapping latest activation basal lateral tricuspid annulus. Pacing this site simultaneously Bundle narrowed significantly improved RVEF dyssynchrony on intracardiac echocardiography. Fick output index to 4.4 2.4 respectively 3.7 2.0 baseline. Thus, removed old replaced new DF-1 defibrillator (Medtronic, Minneapolis, MN) apical septum. Then, SelectSecureTM (3830 model, Medtronic, MN). Non-selective capture threshold 1.0 V 0.4 ms. Y-adapted LV (4196Y which branch CS. HBP resulted 120ms. At follow up, she has not had HF admissions. Simultaneous be feasible strategy patients dysfunction.