Measurement of electrical dyssynchrony in CRT patients: 12-lead ECG versus 96-lead body surface map

Abstract

Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant agency AZV, Ministry of Health of the Czech Republic Background Quantification of electrical dyssynchrony would allow optimization of lead placement and timing in patients with CRT. The standard deviation of activation times (SDAT) derived from body surface maps (BSM) was proposed as a measure of electrical dyssynchrony in CRT patients. However, SDAT derived from standard 12-lead ECG would be clinically preferred. Objective To evaluate and compare the SDAT measured from BSM and 12-lead ECG for assessment of electrical resynchronization in patients with implanted CRT. Methods CRT patients with sinus rhythm and LBBB at baseline (n=19, 58% males; age 60±11 years; NYHA class II-III; QRS 160±29) were studied using 96-lead BSM. For each ECG lead, the activation time was automatically detected and SDAT was calculated using either 96 leads or standard 12 leads. Electrical dyssynchrony was assessed during native sinus rhythm and 6 different pacing modes (see figure). Results SDAT calculated from BSM and 12-lead ECG decreased during optimal BiV pacing as compared to sinus rhythm by 26% (p=0.006) and 30% (p=0.003), respectively. The two other BiV setups showed also a decrease in SDAT values. Importantly, a high degree of reliability was found between values of SDAT obtained from12-lead ECG and 96-lead BSM for different pacing modes, the intraclass correlation coefficient was 0.8 to 0.9 (95% CI 0.7 - 0.9, p<0.001). Conclusion SDAT assessment is considered an important metric of electrical dyssynchrony in CRT. Our results suggest that 12-lead ECG provides similar results as BSM and thus, allows simplification of the measurement. Further prospective studies are necessary to verify the clinical utility of SDAT from 12-lead ECG.