Abstract 1827: T-wave Morphology in The Long QT-Syndrome
Introduction Morphological differences in the T-wave appearance have been qualitatively described in the Long QT syndrome (LQTS). T-wave morphology has been used to separate LQTS types from each other and to identify LQTS-patients with borderline QTc-prolongation. Our aim was to quantify these differences between healthy controls, KvLQT1 and HERG subpopulations.
Method 1087 digital ECGs from a healthy population’s database, 314 ECG’s from 38 patients in a genotyped KvLQT1 database and 250 ECG’s from 41 patients in a genotyped HERG database were submitted for analyses. Flucidal points were assigned to QRS-complex and the T-wave. The T-wave was then characterized with parameters depicting duration, amplitude, area, slope and distribution. For each T-wave a Tonset, Tpeak and Tend was defined corresponding to the T-wave start, top and end, allowing for calculating the parameters in localized areas of the T-wave, e.g. Tpeak-Tend interval (TpTe). A Student t-test was used to test for significant (p<0,05) differences of the means. The distribution parameters compare the T-wave to a Gaussian distribution, using skewness and flatness. The parameters are defined in table 1⇓.
Results The result of the T-wave morphology analysis is presented in table 2⇓.
Conclusion: Healthy controls, patients with KvLQT1-mutations and HERG-mutations differentiate in T-wave morphology in almost all investigated parameters, including parameters other than QT-intervals. This provides an objective aid in LQTS diagnostics beyond QT-interval measurements, and can prove useful in drug development and in the acquired Long QT-Syndrome.