In adult patients suspected of PE traditional Wells score will be calculated and vein and lung US (multiorgan US) will be performed in all patients and and US Wells score calculated. The US Wells score differs from the traditional Wells score in the following items: "signs and symptoms of DVT", replaced by "vein US showing DVT", and "alternative diagnosis less likely than PE" replaced by "alternative diagnosis less likely than PE after multiorgan US". This latter item is considered positive if at least one subpleural infarct is detected at lung US, and negative if no subpleural infarcts are detected and an alternative diagnosis like pneumonia, pleural effusion or diffuse interstitial syndrome may explain the symptoms of presentation. If no findings are detected at lung US, the points for the item remain the same assigned by traditional Wells score. Final diagnosis of PE will be preferentially established by MCTPA and in patients discharged without a second level imaging test because of negative Wells or d-dimer, and patients with not conclusive second level diagnostic test, will enter the 3 months follow-up protocol.