Abstract 16839: Both Short and Long Tpeak-to-Tend Interval is Associated with Increased Mortality: Results from the Copenhagen ECG Study

Abstract

Background The interval from the peak to the end of the T-wave (TpTe) is thought to reflect dispersion of cardiac repolarization and the interval has been suggested to be a marker of ventricular arrhythmogenicity. However, conflicting reports have associated both a shortened and a prolonged TpTe interval with an adverse outcome. We aimed to investigate the risk of death as a function of TpTe interval in the general population.

Methods We included about one third of the population (326,959 individuals) in the greater region of Copenhagen. Since 2001 these individuals had one or more electrocardiograms (ECGs) recorded and stored digitally in a general practitioner core facility. All ECG analyses were performed using computer algorithms. The lead V5 TpTe interval at inclusion (first ECG) was the predictor of interest and all-cause mortality was the primary outcome. Individuals were followed with the use of Danish registers allowing for complete follow-up. Age, gender, hypertension, Charlson comorbidity index, and the use of heart rate corrected QT (QTc) interval prolonging drugs at the day of inclusion were identified as important confounding factors, and Cox proportional hazard models were adjusted for these factors accordingly.

Results The median follow-up time was 5.2 years (interquartile range 2.6-7.8 years). During follow-up, 26,170 individuals died. Multivariable adjusted results showed a u-shaped association between TpTe interval and the risk of death with the lowest risk around a TpTe interval of 102 milliseconds (ms; Figure). Having a TpTe interval in the lowest decile (<78 ms) was associated with a HR of 1.38 (95% confidence interval [CI] 1.32-1.1.45, P 110 ms) was associated with a HR of 1.13 (95% CI 1.07-1.19, P < 0.001) as compared to the lowest-risk decile.

Conclusion Both a short and a long TpTe interval were associated with an increased risk of death.