Redundancy reduction for improved display and analysis of body surface potential maps. II. Temporal compression.
Redundancy reduction for improved display and analysis of body surface potential maps. II. Temporal compression.
复制标题
减少冗余以改进体表电位图的显示和分析。
DOI:
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发表时间:
1981
影响因子:
20.1
通讯作者:
J. .. Abildskov
中科院分区:
文献类型:
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作者:
A. Evans;R. Lux;M. Burgess;R. Wyatt;J. .. Abildskov
This paper describes use of the Karhunen-Loeve expansion to identify and reduce temporal redundancy in electrocardiographic body surface potential maps (192 body surface leads recorded simultaneously at 1 kHz/channel for approximately 600 msec). Temporal data compression of about 20 to 1 was obtained with accurate representation of the original data. Use of separate sets of orthonormal basis functions for QRS and ST-T provided a more accurate representation than the basis derived from QRST. Combined with the spatial compression described in the preceding paper, overall map data compression of about 320 to 1 was obtained without significant loss of accuracy of representation or map appearance. With both spatial and temporal compression the 100,000 numbers which typically comprise a single cardiac complex were accurately represented by 216 coefficients. Using basis functions derived from a single cardiac complex were accurately represented by 216 coefficients. Using basis functions derived from a training set of 221 maps, the estimated average rms error of representation was 60 microV during the ST-T. For 34 test maps which were not part of the training set, measured average errors were 64 microV during the QRS and 23 microV during the ST-T. This technique provides a basis for quantification of the diagnostic content of maps and automated classification of maps.