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Reduced high-frequency QRS components in patients with ischemic heart disease compared to normal subjects
Elin Trägårdh1, Olle Pahlm, Galen S Wagner
1Department of Clinical Physiology, Lund University, Lund, Sweden. elin.tragardh.202@student.lu.se
Abstract:
Analysis of high-frequency QRS components (HF-QRS) might provide an additional method when diagnosing various heart diseases, for example ischemic heart disease (IHD). This study compares HF-QRS in normal subjects to those in patients with IHD, and also analyzes HF-QRS considering gender and age. A total of 63 normal subjects and 64 patients with IHD were included. Signal-averaged electrocardiograms (ECGs) from the 12 standard leads were analyzed in the frequency interval of 150-250 Hz. The results showed that the summed 12 lead HF-QRS in patients with IHD were significantly lower than in normal subjects (mean summed HF-QRS was 33.5 microV in the IHD group, 43.7 microV in normal individuals, P <.0005). HF-QRS were not statistically associated with gender or age (P =.820 and P =.573, respectively). However, the inter-individual variation of HF-QRS was large in both groups which probably limits the clinical usefulness of the method.
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