<原著>拡大高速記録心電図について : 主として高域遮断周波数の影響について

Abstract

The abnormal P wave is important to diagnosis of right atrial hypertrophy or left atrial hypertrophy. R.H. Wasserburger has found, the T-a wave depression of 0.75mm or more in standard Lead II is highly suggestive of advance pulmonary emphysema. But it is difficult to measure precisely the width and the voltage of P wave and T-a wave depression, because the P wave may be of very low voltage and short time in standard electrocardiogram. We have made new apparatus to obtain high speed magnified electrocardiogram (100mm/sec. in speed, 16 times in amplification) Using this apparatus, we have taken electrocardiogram in I II III and _aV_F. Filters in amplifier are used high cut 20Hz, 30Hz, 60Hz, 90Hz, and 180Hz. Among these filters, in high cut 60Hz and 90Hz, we obtained the most detailed changes of P wave.