Could We Really Determine the Duration of the T-Wave? An Answer Comes from T-Wave Triggered Signal Averaged ECG

摘要

We introduced a new, computer-interactive method of determination of the beginning and the ending of the T -wave, which based on T-wave triggered signal-averaged ECG. This method assumes, that critical points could be recognized as nadir of the curve, representing time-related changes of the ratio of 23.5-121.6/0-23.5Hz frequency contents over scanned on-set and off-set regions. The new method was tested in 10 healthy subjects and 20 patients after myocardial infarction. This method allows to measure the duration of QT and T-wave. For comparisons manual measurements were also obtained. T-wave duration and dispersion assessed semi-autotnatically on SAECG was longer or similar (respectively) than manually determined one and weak or none correlations existed between these both methods. Simultaneously, there were good correlations between both methods for QT duration and dispersion, which confirm the accuracy of the T-wave off-set determination.