A Longer T-T Interval Is Associated with a Higher Risk of Death: A Meta-Analysis.

A noninvasive tool for cardiovascular risk stratification has not yet been established in the clinical routine analysis. Previous studies suggest a prolonged T-T interval (the interval from the peak to the end of the T-wave) to be predictive of death. This meta-analysis was designed to systematically evaluate the association of the T-T interval with mortality outcomes. Medline (via PubMed), Embase and the Cochrane Library were searched from 1 January 2008 to 21 July 2020 for articles reporting the ascertainment of the T-T interval and observation of all-cause-mortality. The search yielded 1920 citations, of which 133 full-texts were retrieved and 29 observational studies involving 23,114 patients met the final criteria. All-cause deaths had longer T-T intervals compared to survivors by a standardized mean difference of 0.41 (95% CI 0.23-0.58) and patients with a long T-T interval had a higher risk of all-cause death compared to patients with a short T-T interval by an overall odds ratio of 2.33 (95% CI 1.57-3.45). Heart rate correction, electrocardiographic (ECG) measurement methods and the selection of ECG leads were major sources of heterogeneity. Subgroup analyses revealed that heart rate correction did not affect the association of the T-T interval with mortality outcomes, whereas this finding was not evident in all measurement methods. The T-T interval was found to be significantly associated with all-cause mortality. Further studies are warranted to confirm the prognostic value of the T-T interval.