Diagnostic accuracy of focused cardiac and venous ultrasound examinations in patients with shock and suspected pulmonary embolism

Evaluating the diagnostic performance of focused cardiac ultrasound (US) alone and combination with venous US in patients with shock and suspected pulmonary embolism (PE). Consecutive adult patients with shock and suspected PE, presenting to two Italian emergency departments, were included. Patients underwent cardiac and venous US at presentation with the aim of detecting right ventricular (RV) dilatation and proximal deep venous thrombosis (DVT). Final diagnosis of PE was based on a second level diagnostic test or autopsy. Among the 105 patients included in the study, 43 (40.9%) had a final diagnosis of PE. Forty-seven (44.8%) patients showed RV dilatation and 27 (25.7%) DVT. Sensitivity and specificity of cardiac US were 91% (95% CI 80-97%) and 87% (95% CI 80-91%), respectively. Venous US showed a lower sensitivity (56%, 95% CI 45-60%) but higher specificity (95%, 95% CI 88-99%) than cardiac US (both p < 0.05). When cardiac and venous US were both positive (22 out of 105 patients, 21%) the specificity increased to 100% (p < 0.01 vs cardiac US), whereas when at least one was positive (54 out of 105 patients, 51%) the sensitivity increased to 95% (p = 0.06 vs cardiac US). Focused cardiac US showed good but not optimal sensitivity and specificity for the diagnosis of PE in patients presenting with shock. Venous US significantly increased specificity of cardiac US, and the diagnosis of PE can be certain when both tests are positive or reasonably excluded when negative.