Pulmonary embolism originated from right heart chamber thrombus: the diagnostic role of transesophageal echocardiography

Background

Pulmonary embolism (PE) usually arises from the thrombi originating in the deep venous system of the lower extremities, pelvic or renal vein; however, it may rarely originate in the upper extremity veins and the right heart chambers. Ninety per cent of all pulmonary emboli arise from the deep venous system, usually from the lower extremities. In symptomatic patients, venous ultrasonography has a sensitivity of 95%, a specificity of 96%, a positive predictive value of 97%, and a negative predictive value of 98%. Rarely the source of emboli may be the right atrium, or the thrombi stagnate in the right heart chambers. Transthoracic or transesophageal echocardiography may directly visualize embolized thrombi (right heart chambers or central pulmonary arteries). The incidence of PE is 0.5–1/1000 cases.

Materials and methods

Eleven patients with massive pulmonary embolism, age 36–91 (median 72) years, were treated in the ICU between January 2001 and July 2004. Searching for the source of embolism, venous ultrasonography of lower extremities and transesophageal echocardiography (TEE) were performed. The right heart chambers thrombus could be visualized with TEE; distal embolization of the thrombus into the pulmonary vasculature was suspected. The first and conclusive examination of massive PE is TEE. The presence of intracardial thrombus was enough in itself to indicate thrombolysis therapy. Eleven patients were treated in our study with massive PE. All the patients received tissue plasminogen activator (rt-PA), 100 mg over 2 hours, and continuous echocardiographic monitoring demonstrated clot dissolution within 1 hour in all patients.

Results

There was no re-embolism into the pulmonary vessels during the thrombolysis. There was in one case moderate haemorrhagic complication. One patient died in PE because of the insufficiency of thrombolysis. Nine patients out of 11 should have treated mechanical ventilation. Ten patients were discharged.

Conclusions

Due to the low number of patients our statements are tendency and nondescript. The right heart chamber thromboses verified by TEE are effectively treated with rt-PA. Based on our opinion the lysis activity of rt-PA was faster and more effective than the treatment of streptokinase.