Risk stratification in normotensive acute pulmonary embolism patients: focus on the intermediate-high risk subgroup.

Background: Patients with acute pulmonary embolism are at intermediate-high risk in the presence of imaging signs of right ventricular dysfunction plus one or more elevated cardiac biomarker. We hypothesised that intermediate-high risk patients with two elevated cardiac biomarkers and imaging signs of right ventricular dysfunction have a worse prognosis than those with one cardiac biomarker and imaging signs of right ventricular dysfunction.

Methods: We analysed the cumulative presence of cardiac biomarkers and imaging signs of right ventricular dysfunction in 525 patients with intermediate risk pulmonary embolism (intermediate-high risk = 237) presenting at the emergency department in two centres. Studied endpoints were composites of all-cause mortality and/or rescue thrombolysis at 30 days (primary endpoint; =58) and pulmonary embolism-related mortality and/or rescue thrombolysis at 30 days (secondary endpoint; =40).

Results: Patients who experienced the primary endpoint showed a higher proportion of elevated troponin (47% vs. 76%, <0.001), elevated N-terminal pro-brain natriuretic peptide (67% vs. 93%, <0.001) and imaging signs of right ventricular dysfunction (47% vs. 80%, <0.001). Multivariate analysis revealed N-terminal pro-brain natriuretic peptide (hazard ratio (HR) 3.6, 95% confidence interval (CI) 1.3-10.3; =0.015) and imaging signs of right ventricular dysfunction (HR 2.8, 95% CI 1.5-5.2; =0.001) as independent predictors of events. In the intermediate-high risk group, patients with two cardiac biomarkers performed worse than those with one cardiac biomarker (HR 3.3, 95% CI 1.8-6.2; =0.003).

Conclusions: Risk stratification in normotensive pulmonary embolism should consider the cumulative presence of cardiac biomarkers and imaging signs of right ventricular dysfunction, especially in the intermediate-high risk subgroup.