Non-invasive assessment of left ventricular activation delay for identifying cardiac resynchronization therapy responders using ultra-high-frequency electrocardiogram

Autores de IIS La Fe

• Óscar Cano Pérez

  Autor

Participantes ajenos a IIS La Fe

• Poviser L.
• Stros P.
• Leinveber P.
• Smisek R.
• Vesela J.
• Curila K.

Grupos

• Grupo de Investigación Clínica y Traslacional en Cardiología

Abstract

Background Ultra-high-frequency electrocardiogram (UHF-ECG) which visualizes electrical ventricular dyssynchrony may be a valuable tool for improving the selection and treatment of patients with indication to cardiac resynchronization therapy (CRT). Objective This study aimed to compare non-invasive assessment of left ventricular (LV) delay using UHF-ECG with invasive QLV in CRT candidates, and to evaluate whether UHF-ECG can identify patients who will achieve resynchronization and LV reverse remodeling after biventricular CRT. Methods Consecutive patients undergoing CRT at 2 centers were included. QLV was measured in basal, midventricular, and apical LV segment. UHF-ECG LV delay was measured from QRS onset to local activation in leads V5–V8. Global LV dyssynchrony (lv-DYS) was assessed during spontaneous rhythm and pacing from the earliest activation to the latest activation in leads V5–V8 and was used to identify CRT responders. Results 48 patients were included (75% male, age 67 ± 12 years, LV ejection fraction 31 ± 6%, QRSd 167 ± 20 ms). UHF-ECG in V8, V7, and V6 did not differ from QLV in the basal, midventricular, or apical segments (mean differences: 3 ± 14 ms, <ani:em>P =</ani:em>.52; -3 ± 17 ms, <ani:em>P =</ani:em>.18 and 0 ± 17 ms, <ani:em>P =</ani:em>.92) and strong correlation was observed between them (r = 0.84, <ani:em>P</ani:em> <.001).The lv-DYS strongly correlated with the longest QLV (r = 0.76, <ani:em>P</ani:em> <.001). Patients with baseline lv-DYS >58 ms showed a more significant reduction in lv-DYS and were more often responders to CRT than patients with shorter values ( lv-DYS -70 ms vs -8 ms, and responders 97% vs 32%). Conclusion UHF-ECG enables non-invasive assessment of QLV and can help with identification of patients who will benefit from CRT. © 2026 Heart Rhythm Society.

Keywords

• aged; article; cardiac resynchronization therapy; controlled study; electrocardiogram; electrocardiography; female; heart left ventricle; heart left ventricle ejection fraction; human; male; therapy