Value and Limits of Doppler Ultrasound and M-Mode Echocardiography in the Assessment of the Efficacy of Fibrinolysis in Pulmonary Embolism

Abstract

The efficacy of fibrinolytic therapies in pulmonary embolism (PE) was prospectively studied by Doppler echocardiography (DE). The evolution of the imaging and Doppler echographic parameters was compared with the angiographic evolution. Twenty-two patients presenting a severe PE with a vascular obstruction percentage (VOP) of more than 40% were included in the study. The following parameters were recorded before and after thrombolysis: the systolic pulmonary arterial pressure (sPAP) was assessed from the tricuspid regurgitation (TR) flow using continuous-wave (CW) Doppler, and the right and left ventricular diastolic diameters (RVD and LVD) were measured using echographie M-mode examination. All the PE were severe (VOP = 68 ± 10%) with pulmonary hypertension (sPAP = 53.5 ± 10 mm Hg). The improvement of the VOP averages 34%. The average sPAP dropped from 53.5 ± 10 to 34.5 ± 11 mm Hg and the RVD from 31.5 ± 6.5 to 25 ± 5.5 mm. The LVD rose from 39.5 ± 7 to 43.5 ± 6 mm. The RV/LV ratio dropped from 0.82 to 0.59 (p < 0.005). In 6 cases, the treatment was proved inefficient at the angiographic control with an improvement of the VOP inferior to 20%. The persistence of a pulmonary hypertension at the control CW signed an angiographic failure of the fibrinolysis. Whereas the regression of the pulmonary hypertension was an inconstant sign of an angiographic success, the reduction of the right ventricular diameter was a sure indication of a significant pulmonary reperfusion.