Introduction: Pulmonary embolism (PE) is a disease with increasing incidence and prevalence, due to rising prevalence of predisposing factors. The patients pre-senting both echocardiographic and biochemical signs (increased Nt-pro BNP) of right ventricular (RV) over-load are included in the intermediary-high risk. The echocardiographic signs of RV overload are the RV di-latation, the ratio between the diastolic diameters RV/ LV >1, the decrease of the myocardial contraction velo-city (MCV), the presence of the dyskinesia of the inter-ventricular septum (IVS). Intermediary risk is defined by PESI score >85 and associating the biochemical and echocardiographic signs of RV dysfunction.

Methods: In the present study I selected 65 patients with intermediary – high risk PE. The inclusion crite-ria were: a) The first documented acute PE – not more than 2 weeks from start -; b) Echocardiographic and biochemical markers of RV dysfunction present. The exclusion criteria were : a) history of PE ; b) Age >80 y.o.; c) Severe systolic dysfunction of LV (LV ejection fraction <35%); d) Pre-existing primary or secondary pulmonary arterial hypertension (caused by aortic or mitral valvulopathies); e) end-stage neoplasm ; f) Di-seases associated with severe coagulopathies: hemophi-lic syndromes, liver cirrhosis; g) psychiatric disorders associated with impossibility of signing an informed consent; h) severe anemic syndromes (Hb <8g/dl)

Results: The patients were divided in two groups, the study group (treated with thrombolytic and anticoagu-lant therapy) and control group (anticoagulant therapy alone). The criteria for selecting patients in study group were: 1. Absence of contraindications for thrombolytic therapy; 2. Body mass index (BMI) 18.5 – 29.9; 3. Ab-sence of severe renal dysfunction (GFR >30 ml/min/ m²); 4. Absence of the known allergy on ateplase. The RV dysfunction parameters were evaluated on admis-sion, the echocardiographic re-assessment was perfor-med on 72 h. We assessed comparative the variation of the markers of RV dysfunction in the two groups. We proved the statistical significant correlation betwe-en the RVEDD and early mortality and haemodynamic instability in the thrombolysed group (Pearson coeffi-cient 0.84 and 0.68, RVEDD critical value 48mm and 46 mm, p=0.046 and 0.04) and also the statistical sig-nificant correlation between the RVEDD/LVEDD >1 and early mortality and haemodynamic instability in the thrombolysed group (Pearson coefficient 0.82 and 0.71, p=0.042 and p=0.04). All of the echocardiogra-phic markers were statistically significant improved in the thrombolysed group compared to control group Conclusions: T he thrombolytic therapy in patients with intermediary-high risk PE can bring benefits re-garding clinical and haemodynamical markers, the proper selection of these patients regarding the values of echocardiographic and biochemical markers of RV dysfunction being essential.