It is well recognised by hands-on clinicians that patients who present acutely with haemodynamic compromise and hypotension with a systolic pressure of <90 mm Hg due to acute pulmonary embolism (PE) have a poor prognosis. This is reflected in current British Thoracic Society guidelines in the management of acute PE which recommend aggressive interventions in this population, with thrombolysis as first-line treatment.1

However, stratification of mortality and morbidity risk in normotensive patients who present with acute PE is less clear. Demonstration of right ventricular dysfunction or dilatation on either echocardiography or spiral HRCT scanning of the chest has been used as a potential indicator of those requiring more aggressive treatment even if normotensive. Immediate availability of these modalities is not universal, and a simpler way of identifying those patients at highest risk of adverse events and mortality remains critical as the inpatient mortality rate for normotensive patients with acute PE is approximately 10%.2 A number of previous studies have attempted to identify biomarkers which have prognostic power in patients with acute PE. Many of these studies have focused on cardiac biomarkers including the troponins and natriuretic peptides which correlate with right ventricular dysfunction on echocardiography.3 Whether these systemic biomarkers correlate with an …