Correlation between Pulmonary Vascular Resistance and Some Cardiac Indices

Background: The Pulmonary Vascular Resistance (PVR) index is an important hemodynamic variable in making determinations regarding cardiopulmonary diseases and can be measured echocardiographically. The objective of this report is to examine the relationship between echocardiographic parameters of ventricular function using PVR measurements.

Materials and Methods: This study included 40 patients. PVR and left ventricular function indexes (left ventricle diastolic function and Systolic Pulmonary Arterial Pressure (SPAP)) were measured echocardiographically and analyzed using a linear regression test. The relationship between the right ventricular Tricuspid Annular Plane Systolic Excursion (TAPSE) index and the mean PVR index was assessed with the Mann–Whitney test using SPSS Ver. 15.

Results: A comparison between PVR and TAPSE showed that the mean PVR was significantly reduced when TAPSE increased, with a cut-off point of 1.8 (P= 0.026). Examination of the relationship between SPAP and PVR made it clear that increased SPAP (mean PAP>25 mmHg) caused PVR to significantly increase (P<0.0001). Analysis of the relationship between LVEF and PVR showed that PVR decreased significantly in parallel with an increasing ejection fraction (P= 0.004). Determination of the mean PVR in the LV Diastolic dysfunction group showed that the mean difference between the PVR indexes of the LV diastolic dysfunction group and the restrictive pattern group was significantly higher than the mean difference between the PVR indexes of the LV diastolic dysfunction group and the normal group(P<0.0001).

Conclusion: Considering the significance of PVR measurement in treating cardiovascular diseases, we recommend echocardiography as a simple, accessible and noninvasive method for determining this metric. In this study, we demonstrated that the strongest relationship between echocardiographically determined measurements exists for the correlation between PVR and diastolic dysfunction and the grades thereof. This method can be used as an accessible method for determining PVR and as an index for assessing prognosis.