Optimized CRT Stimulation Based on Ultra-High-Frequency QRS Analysis

The optimization of cardiac resynchronization therapy (CRT) stimulation by ultra-high-frequency ECG (UHF-ECG) is presented.34 subjects (24 men, aged 65.0±10.1) undergoing the implantation of a CRT_D with an automatic optimizing algorithm for atrioventricular and intraventricular delay. Interventricular delay (IVD) from echocardiography and electrical dyssynchrony (e-DYS) from UHF-ECG were analysed using three different CRT configurations - OFF (stimulation off), SMART (SMART algorithm) and OPT (optimal assessment subjectively determined by the electrical depolarization map from UHF-ECG).The mean±STD values over visits for IVD [ms] were 50.32±29.00, 29.09±29.33 and 25.17±24.54 for OFF, SMART and OPT respectively. For e-DYS [ms], it was 69.18±30.85, 31.18±24.42 and 13.42±18.67 for OFF, SMART and OPT respectively. Significant statistical differences (p<0.01) existed between OFF and both SMART and OPT for both IVD and e-DYS parameters. Between SMART and OPT, significant differences (p<0.01) existed only for e-DYS.UHF-ECG analysis may be used to optimize CRT stimulation and to minimize electrical dyssynchrony.