THE INFLUENCES OF RESPIRATION ON THE QRS IN ELECTROCARDIOGRAM
呼吸对心电图中QRS波形的影响

By the statistic analysis of Flank lead ECG of 20 healthy normal male subjects, it was found that the amplitudes of the QRS complex were different between the respiration phases. Since the most significant difference happened between the middle phase of expiration and the middle phase of inspiration, this result implies that it is the intrapulmonary pressure and the cardiac volume, but not the relative position of the heart and electrodes, which cause the variation of the amplitude of QRS complex.