An algorithm for QRS onset and offset detection in single lead electrocardiogram records

In this paper a new algorithm is proposed for QRS onset and offset detection in single lead electrocardiogram (ECG) records. In each cardiac cycle, the R peak is first detected to serve as a reference to delimit the search windows for the QRS onset and offset. Then, an auxiliary signal is defined from the envelope of the ECG signal. Finally, a statistical hypothesis test is applied to the auxiliary signal in order to detect mean changes. The performances of the algorithm have been evaluated using the PhysioNet QT database. The mean and standard deviation of the differences between onsets or offsets manually marked by cardiologists and those detected by the proposed algorithm are computed. The standard deviations obtained in this work are around the tolerances accepted by expert physicians, and slightly outperform the results obtained by the other known algorithms evaluated with the same database.