Consecutive adult patients presenting to the emergency department at Azienda Ospedaliero-Universitaria Careggi with the first episode of pulmonary embolism were included. Patients with systolic blood pressure less than 100 mm Hg were excluded. ECG and echocardiography were performed within 1 hour from diagnosis and evaluated in a blinded fashion. Right ventricular strain was diagnosed in the presence of one or more of the following ECG findings: complete or incomplete right ventricular branch block, S1Q3T3, and negative T wave in V1-V4. The main outcome measurement was clinical deterioration or death during in-hospital stay. The association of variables with the main outcome was evaluated by multivariate Cox survival analysis.
A total of 386 patients with proved pulmonary embolism were included in the study; 201 patients (52 % ) had right ventricular dysfunction according to echocardiography, and 130 patients (34 % ) showed right ventricular strain. Twenty-three patients (6 % ) had clinical deterioration or died. At multivariate survival analysis, right ventricular strain was associated with adverse outcome (hazard ratio 2.58; 95 % confidence interval, 1.05-6.36) independently of echocardiographic findings. Patients with both right ventricular strain and right ventricular dysfunction (26 % ) showed an 8-fold elevated risk of adverse outcome (hazard ratio 8.47; 95 % confidence interval, 2.43-29.47).
Right ventricular strain pattern on ECG is associated with adverse short-term outcome and adds incremental prognostic value to echocardiographic evidence of right ventricular dysfunction in patients with acute pulmonary embolism and normal blood pressure.