The authors review the importance of echocardiography and duplex examination of the blood vessels of the lower extremities for early diagnosis of thromboembolic attacks. Echocardiographic examination rules out other causes of the patient's complaints such as myocardial infarction, heart defects, ischaemic heart disease and others. The main role of echocardiography is, however, detection of symptoms of an acute rise of the blood pressure in the right heart or symptoms of its failure. The most valuable symptom is dilatation of the right branch of the pulmonary artery and dilatation of the right ventricle found in as many as 75% patients. It is also useful to assess by the Doppler method the dextrolateral systolic pressure from tricuspidal regurgitation. For pulmonary embolism a regurgitation rate of 2.8-3.8 m/s is typical. The correlation coefficient is, however, lower than when the dimensions of the right and left ventricle are used. Evidence of deep venous thrombosis does not reveal pulmonary embolism but has the same therapeutic consequences. Duplex sonography has a 95-100% sensitivity and specificity in acute thrombosis. In recurrent thrombosis it is necessary to use a combination of the two methods. Concurrent echocardiography and duplex sonography of the blood vessels of the lower extremities makes it possible to start prompt treatment in 70-80% of the patients. In the remainder for diagnosis of thromboembolic attacks other methods must be used.

Keywords: Humans; Thromboembolism /diagnostic imaging/; Ultrasonography