Repolarization Heterogeneity Measured With T-Wave Area Dispersion in Standard 12-Lead ECG Predicts Sudden Cardiac Death in General Population.

Abstract

We developed a novel electrocardiographic marker, T-wave area dispersion (TW-Ad), which measures repolarization heterogeneity by assessing interlead T-wave areas during a single cardiac cycle and tested whether it can identify patients at risk for sudden cardiac death (SCD) in the general population. TW-Ad was measured from standard digital 12-lead ECG in 5618 adults (46% men; age, 50.9±12.5 years) participating in the Health 2000 Study-an epidemiological survey representative of the Finnish adult population. Independent replication was performed in 3831 participants of the KORA S4 Study (Cooperative Health Research in the Region of Augsburg; 49% men; age, 48.7±13.7 years; mean follow-up, 8.8±1.1 years). During follow-up (7.7±1.4 years), 72 SCDs occurred in the Health 2000 Survey. Lower TW-Ad was univariately associated with SCD (0.32±0.36 versus 0.60±0.19; P<0.001); it had an area under the receiver operating characteristic curve of 0.809. TW-Ad (≤0.46) conferred a hazard ratio of 10.8 (95% confidence interval, 6.8-17.4; P<0.001) for SCD; it remained independently predictive of SCD after multivariable adjustment for clinical risk markers (hazard ratio, 4.6; 95% confidence interval, 2.7-7.4; P<0.001). Replication analyses performed in the KORA S4 Study confirmed an increased risk for cardiac death (unadjusted hazard ratio, 5.5; 95% confidence interval, 3.2-9.5; P<0.001; multivariable adjusted hazard ratio, 1.9; 95% confidence interval, 1.1-3.5; P<0.05). Low TW-Ad, reflecting increased heterogeneity of repolarization, in standard 12-lead resting ECGs is a powerful and independent predictor of SCD in the adult general population.