A Clinical Study On Evaluation Of Right Ventricular Myocardial Function In Patients With Pulmonary Arterial Hypertension Using Speckle Tracking Imaging Technique

ObjectiveUsing 2D-Speckle tracking imaging technology (2D-STI) to analysis right ventricular myocardial longitudinal peak systolic strain (LS) and longitudinal peak systolic strain rate (LSRs) quantitatively in patients with pulmonary arterial hypertension (PAH). To evaluate the right ventricular myocardial global peak longitudinal strain (GLS) and strain rate (GLSRs) change in pulmonary artery pressure in mild, moderate and severe groups. To discuss the value of clinical application in PAH patients which were valued by STI technology.MethodsApplication of Philips IE ELITE ultrasonic diagnostic apparatus, equipped with S5-1 probe (frequency 1-5MHz). Applying STI technology echocardiography to evaluate 43 patients in PAH (mild-PAH 18, mod-PAH 15, severe-PAH 10) and 40 cases in the control group of healthy volunteers. All the patients were collected the two-dimensional gray-scale levels of dynamic images for apical four-chamber view in three consecutive cardiac cycles. Tracing and analyzing images section above by a kind of offline ultrasound analysis software named Qlab 9.1. Calculating myocardial systolic LS and LSRs for each segment separately, generating corresponding curves, the right ventricular GLS and GLSRs. Comparing the measured data between groups, and taking the measured corresponding parameters and pulmonary artery systolic pressure (PASP) and right ventricular end-diastolic diameter (REVDD) with correlation analysis.ResultComparing patients in PAH to controls, LS and LSRs of the right ventricular free wall and interventricular septal segments decreased significantly, the difference was statistically significant (P<0.05).Comparing patients in mild-PAH, mod-PAH and severe-PAH groups to control group, GLS and GLSRs of the right ventricular myocardial decreased significantly, the difference was statistically significant (P<0.05). Comparing severe-PAH group to mild-PAH group, GLS decreased significantly, he difference was statistically significant (P<0.05). No statistically significant difference was found among mild-PAH, mod-PAH, and severe-PAH groups (P>0.05).There was significant correlation between PASP and right ventricular GLS and GLSRs (r =-0.552, P<0.01; r=-0.472, P<0.01). No significant correlation between RVEDD and right ventricular GLS and GLSRs (r=-0.053, P>0.05; r=-0.108,.P>0.05)ConclusionThe right ventricular myocardial motion and systolic function in PAH group decreased significantly, with the increased pulmonary artery pressure, the right ventricular dysfunction becomes more obviously. Application of 2D-STI technology can be used for the quantitative evaluation of the right ventricular myocardial strain and strain rate in patients with PAH. It also provides a strong reference for clinical evaluation of right ventricular myocardial function and treatment effect in PAH patients.