Gellert KS, Rautaharju P, Snyder ML, Whitsel EA, Matsushita K, Heiss G, Soliman EZ. Short-term repeatability of electrocardiographic Tpeak-Tend and QT intervals.
J Electrocardiol 2014;
47:356-61. [PMID:
24792986 DOI:
10.1016/j.jelectrocard.2014.03.002]
[Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2013] [Indexed: 01/22/2023]
Abstract
BACKGROUND
The electrocardiographic (ECG) Tpeak-Tend interval (TpTe) is associated with arrhythmias and sudden cardiac death. TpTe offers a supplementary measure for the QT interval (QT), yet its repeatability has not been established.
PURPOSE
Evaluate short-term repeatability of TpTe and QT.
METHODS
Four ECGs were obtained on sixty participants. The sources of variation, intra-class correlation coefficient (ICC) - an index of reproducibility - and minimal detectable change (MDC) were estimated for TpTe and QT. The impact of repeated measurements on repeatability was estimated for a hypothetical clinical trial designed to detect drug-induced prolongation of TpTe and QT.
RESULTS
We used heart rate-adjusted QT [(QT)a] but TpTe in the study group was rate-invariant. The ICC [95% confidence interval (CI)] was 0.77 (0.69, 0.85) for TpTe, 0.75 (0.65, 0.85) for QT and 0.60 (0.47, 0.73) for (QT)a. The MDC (ms) was 21, 32 and 26 for TpTe, QT and (QT)a respectively.
CONCLUSION
TpTe has excellent repeatability supporting its use as a supplement to QT in observational and clinical studies.
Collapse