An effective compression scheme for multilead ECG signals containing ectopie ventricular activation

When recording 64 channel high resolution (0.75μV per bit) eletrocardiograms, datatile compression becomes necessary. It is shown that these files can be stored with 5 bits per sample at 500 Hz sampling rate. The preferred method consists of computing the second order derivative and Huffman encoding of the residue. By using this data compression technique, polymorphic ventricular tachycardia recordings which have a larger information content can be compressed to nearly the same volume as sinus rhythm. It is not necessary to find the optimal Huffman coding for every recording. A fixed encoding scheme can be used without significant increase in file length.