Prediction of sudden cardiac death with automated high-throughput analysis of heterogeneity in standard resting 12-lead electrocardiograms.

BACKGROUND:Heterogeneity of depolarization and repolarization underlies the development of lethal arrhythmias. OBJECTIVE:We investigated whether quantification of spatial depolarization and repolarization heterogeneity identifies individuals at risk for sudden cardiac death (SCD). METHODS:Spatial R-, J-, and T-wave heterogeneity (RWH, JWH, and TWH, respectively) was analyzed using automated second central moment analysis of standard digital 12-lead electrocardiograms in 5618 adults (2588, 46% men; mean ± SEM age 50.9 ± 0.2 years), who took part in the epidemiological Health 2000 Survey as representative of the entire Finnish adult population. RESULTS:During the follow-up period of 7.7 ± 0.2 years, a total of 72 SCDs occurred (1.3%), with an average yearly incidence rate of 0.17% per year. Increased RWH, JWH, and TWH in left precordial leads (V4-V6) were univariately associated with SCD (P < .001 for each). When adjusted with standard clinical risk markers, JWH and TWH remained independent predictors of SCD. Increased TWH (≥102 µV) was associated with a 1.7-fold adjusted relative risk for SCD (95% confidence interval [CI] 1.0-2.9; P = .048) and increased JWH (≥123 µV) with a 2.0-fold adjusted relative risk for SCD (95% CI 1.2-3.3; P = .006). When both TWH and JWH were above the threshold, the adjusted relative risk for SCD was 2.9-fold (95% CI 1.5-5.7; P = .002). When RWH (≥470 µV), JWH, and TWH were all above the threshold, the adjusted relative risk for SCD was 3.2-fold (95% CI 1.4-7.1; P = .009). CONCLUSION:Second central moment analysis of standard resting 12-lead electrocardiographic morphology provides an ultrarapid means for the automated measurement of spatial RWH, JWH, and TWH, enabling analysis of high subject volumes and screening for SCD risk in the general population.