Comparative Study of Oscillation of Pulmonary Artery Pressure to That of Systemic Artery Pressure

Woo, Hyan Ok; Kwon, Hyung Jin; Yum, Myung Kul

Abstract

PURPOSE: The purpose of this study is to examine the difference between the below respiratory-frequency oscillations of the pulmonary artery pressure and those of the systemic arterial pressure.
METHODS
The subjects in this experiment were patients suffering from ventricular septal defect and having treatment with the cardiac catheterization at Gyeongsang National University Hospital. Signals from pulmonary artery pressure, femoral artery pressure and the respiration of the patients were received for 5 minutes and digitalized and stored into the personal computer. Those data were interpreted and compared by the power spectral analysis method.
RESULTS
1) In case that the mean pulmonary artery pressure was below 30mmHg(n=23), the low frequency, the mid frequency, the respiratory frequency and the total frequency power of the pulmonary artery pressure were 4.17+/-0.65(3.15-5.40), 3.81+/-0.66(2.79-4.96), 6.06+/-0.27(5.57-6.83) and 6.78+/-0.34(6.01-7.36) respectively. And the those of the femoral artery pressure were 5.24+/-0.49(4.46-6.13), 4.27+/-0.57(3.34-5.45), 5.54+/-0.44(4.72-6.13) and 7.44+/-0.51(6.07-7.94). So in all the frequency ranges a significant difference was observed between the pulmonary artery pressure and the systemic blood pressure(p<0.01) 2) In case that the mean pulmonary artery pressure was above 30mmHg(n=9), the low frequency, the mid frequency, the respiratory frequency and the total frequency power of the pulmonary artery pressure were 4.86+/-0.80(3.75-5.77), 4.22+/-0.77(3.36-5.28), 6.31+/-0.42(5.42-6.78) and 7.16+/-0.56(6.26-8.01), respectively. Those of the systemic arterial pressure were 5.12+/-0.59(4.14-5.76), 4.24+/-0.60(3.51-4.93), 6.17+/-0.33(5.76-6.59) and 7.47+/-0.06(6.70-8.09). In this case, there was no significant difference was found between the two pressures. In short, when the pulmonary artery pressure was normal range or a little high(<30mmHg), the low-frequency and mid-frequency oscillations were greater in the systemic blood pressure, but the respiratory frequency oscillation was greater in the pulmonary artery pressure. When the pulmonary artery pressure was high rage(>30mmHg), the low frequency oscillation of the pulmonary artery pressure and the respiratory frequency oscillation of the systemic blood pressure were increased, resulting in the same oscillation in the low frequency, the mid frequency, the respiratory frequency and the total frequency.
CONCLUSIONS
The magnitude of ossillation of pulmonary artery pressure was very similar to the magnitude of ossilation of systemic arterial pressure in the below-respiratory-frequency when pulmonary artery pressure was high(>30mmHg).