Is tailored lv only pacing inferior to biventricular pacing in cardiac resynchronization therapy?

Abstract

Thirty percent of the typical patient (P) cohort undergoing cardiacresynchronization therapy (CRT) do not improve clinically in large randomizedtrials. All P were treated with biventricular pacing mode (BI). This study reportson the clinical follow-up in patients resynchronized with tailored LV only pacing. Methods: All P underwent preoperative hemodynamic testing with respect to pacing mode, AV delay and optimal pacing site. Response was defined as ≥10% pulsepressure (PP) increase. A difference of more than 3% PP increase between pacingmodes discriminated the best pacing mode. Ninety-one (23 female 46 P with DCM, 36 with CAD, 9 with other diseases, QRS 185±29 ms, NYHA 3, EF 25±7,2%) of 500 P, who had undergone CRT at our center between 1999 and 2004, showed a significantly higher response in acute testing with the LV pacing mode. Seventy-eight P received a unipolar, 13 a bipolar LV lead. The mean stimulated AV delay was 154±28 ms. During 6- and 9-month follow-up P with tailored LV pacing mode improved highly significantly in quality of life, functional objectives and LVEDD that is LV remodeling (Table).Only 8 P died or were referred to heart transplant during two years of follow-up! Despite historical pseudobipolar pacing in many P with unipolar LV lead tailored LV only pacing is significantly successful and superior to untailored BI pacing. Implantation of bipolar leads and careful tailoring of best chronic pacing mode is the clue to improve the success in CRT.