Pulmonary embolism (PE) remains challenging to diagnose and, in particular, to risk stratify. Many patients with low-risk PE can be managed safely as outpatients with standard anticoagulation. At the other end of the risk spectrum, patients who present with haemodynamic instability, defined as high-risk PE, have a high short-term mortality and require consideration of urgent reperfusion therapy through pharmacologic or mechanical means, alongside critical care support, vasopressors and, when necessary, cardiopulmonary resuscitation. Perhaps the greatest challenge, however, lies between these two extremes with patients who remain normotensive despite evidence of significant cardiopulmonary stress and may still be at risk for clinical deterioration. Identifying which of these intermediate-risk, and particularly intermediate-high-risk, patients will deteriorate is a major challenge in the contemporary management of acute PE.
Developing a more precise understanding of which patient and PE-related factors predict clinical deterioration or death is therefore of significant importance to…