Early diagnosis is important for the prognosis of patients affected with pulmonary embolisms. The mortality rate ranges from 30% in untreated cases to 10% in cases getting early treatment. In this context, it is essential to obtain a correct diagnosis in order to start the best treatment for each patient. The aim of our study is to evaluated the contribution of mono- bidimensional echocardiography and color-doppler for the early diagnosis of acute massive pulmonary embolism. We examined 23 patients (14 women with a mean age of 67 +/- 13 years; 9 men with a mean age of 58 +/- 16 years) who were referred to us for observation over a 30-month period. These patients had been admitted to the intensive care unit for suspected acute massive pulmonary embolism and the diagnosis was subsequently confirmed by a pulmonary scintigraphy. None of the 23 patients showed a positive case history of previous heart disease and/or pulmonary disease. The patients were checked using 2D-doppler echocardiography, 120 +/- 45 minutes from the onset of the symptoms. They were then divided into two groups (A and B) based on the presence or absence of thromboembolus in the right cavity of the heart. Seven patients (30%) revealed thromboemboli and were treated effectively with rt-PA (100 mg/2 hours). An increase in the size of the right ventricle with an affected rate RV/LV > 0.6 and the abnormal kinetics of the ventricular septum proved to be the most sensitive parameters for right ventricular overload, as signs of acute massive pulmonary ambolisms were observed in all 23 patients. Tricuspid regurgitation speed (from 2.9 to 3.6 m/sec) and peak systolic pulmonary pressure (67 mmHg) were recorded in all patients. Our observations suggest that the hemodynamic effects of an acute massive pulmonary embolism can be enumerated and monitored by analyzing ventricle size and septum kinetics. To summarize, echocardiography proved to be a simple and realistic test. It enabled correct diagnosis and made it possible not only to start thrombolytic therapy without requiring other exams, but also to monitor and evaluate the effects of this therapy.