Right heart function in pulmonary embolism: Diagnosis and follow-up with three-dimensional echocardiography and speckle tracking echocardiography.

Purpose. It is known that acute pulmonary embolism (PE) can affect right ventricular (RV) performance. We assessed changes in ventricular parameters determined by three-dimensional echocardiography (3DE) and speckle tracking imaging (STI) before and after long-term PE treatment. Methods. We recruited 21 patients with acute PE confirmed by multidetector row chest computed tomography. 21 healthy subjects without signs of cardiopulmonary dysfunction served as a control group. RV end-diastolic and end-systolic volumes were measured from three-dimensional echocardiographic datasets with "summation of disks" method and right ventricular ejection fraction (3D-RVEF) was calculated. Pulmonary arterial systolic pressure was obtained by standard Doppler methods. Pulmonary hypertension was defined as a pulmonary artery systolic pressure of 40 mmHg or greater. To assess regional and global RV systolic function in the longitudinal direction using STI, we adopted a 6-segment RV model (basal RV lateral wall, mid RV lateral wall, apical RV wall, apical septum, mid septum, and basal septum). RV peak systolic strain and time to peak-systolic strain from the onset of QRS were recorded for the 6 RV myocardial segments and for the entire RV myocardium (EchoPAC BT09, GE Ultrasound). Global longitudinal strain was calculated by averaging local strains along the entire right ventricle using machine software. RV dyssynchrony (RV-SD6) was defined as the standard deviation of the six time to peak systolic strain values. Results. 3D-RVEF was lower in patients with PE and pulmonary hypertension compared to the control group (p<0.001) and compared to patients with PE and normal pulmonary pressure (p<0.05). A significant correlation was found between RV-SD6 and pulmonary artery systolic pressure (r = 0.72, p <0.005). Increased RV-SD6 (>55 ms) and decreased 3D-RVEF (< 45%) persisted in 4/21 pts after one month of medical treatment and in 2/21 pts after one year. By multivariate analysis, RV-SD6 (p=0.007) and 3D-RVEF (p=0.04) were predictive of pulmonary arterial hypertension. Conclusions. Our data show that acute PE has a significant impact on RV function and synchrony, 3D-RVEF and RV-SD6 correlate with pulmonary hypertension and abnormal values may persist long-term during the follow-up of PE pts.