Pulmonary embolism (PE) is a potentially life-threatening condition and the fact that 90% of PE originate from lower limb veins highlights the significance of early detection and treatment of deep vein thrombosis. Massive/high risk PE involving circulatory collapse or systemic arterial hypotension is associated with an early mortality rate of approximately 50%, in part from right ventricular (RV) failure. Intermediate risk/submassive PE, on the other hand, is defined as PE-related RV dysfunction, troponin and/or B-type natriuretic peptide elevation despite normal arterial pressure. Without prompt treatment, patients with intermediate risk PE may progress to the massive category with a potentially fatal outcome. In patients with PE and right ventricular dysfunction (RVD), in hospital mortality ranges from 5% to 17%, significantly higher than in patients without RVD.