CROSS-SECTIONAL DOPPLER-ECHOCARDIOGRAPHY AS THE INITIAL TECHNIQUE FORTHE DIAGNOSIS OF ACUTE PULMONARY-EMBOLISM

Objective-To determine the value of cross sectional Doppler echocardio graphy and derived indices of right ventricular pressure and function in the initial diagnosis of pulmonary embolism. Background-Most deaths from acute pulmonary embolism occur because of a delay in diagnosis. Ventilation-perfusion scans are not sufficiently sensitive, whereas an giography is invasive and associated with complications. The use of cr oss sectional Doppler echocardiography to assess acute changes in righ t ventricular filling pressure and function, and in pulmonary arterial systolic pressure and its relation to embolism has not been studied i n a large population. Methods-60 consecutive patients with acute sympt oms or haemodynamic instability suggestive of pulmonary embolism Confi rmatory investigations included a ventilation-perfusion scan (36 patie nts), angiography (18 patients), surgery (5 patients), or necropsy (5 patients). Results-There was evidence of right ventricular pressure or volume overload in all. This took the form of increased right ventric ular end diastolic diameter and leftward bulging of the interventricul ar septum in diastole (56 patients); tricuspid valve regurgitation (56 patients) with the peak velocity of the regurgitant jet > 2.6 m/s; an d a low collapse index for the inferior vena cava of < 40%, indicating raised mean right atrial pressure (in 49 patients). Intracardiac or p ulmonary thrombi were visualised in 10 patients. In 14 patients treatm ent was undertaken on the basis of the echocardiographic signs alone. Four of them (with visible thrombi) recovered: the other 10 died. Lung emboli were demonstrated in 4 of 5 patients in whom necropsy was perf ormed. Conclusions-Cross sectional Doppler echocardiography is a sensi tive technique for the rapid identification of right ventricular overl oad in acute pulmonary embolism. It enables further investigations on treatment to be appropriately directed without delay. Resolution of em boli can also be assessed by serial measurement of the described indic es.