The Need for Escalation Therapy and Mortality in Intermediate Risk Pulmonary Emboli Patients – Results of a Large Tertiary Center Registry (PLATIS - PE)

Background: Intermediate risk pulmonary embolism (PE) carries a 30 day mortality ≥10% and a significant risk for chronic disability. Results of prospective randomized studies which examined routine thrombolysis and\or invasive intervention in these patients were controversial. The aim of this study was to identify predictors of the need for escalation therapy (catecholamines for hemodynamic instability, ventilation, thrombolysis) and\or in hospital mortality [primary end point (EP)].

Methods: The study comprised 144 consecutive patients with intermediate risk PE. PE was diagnosed based on computed tomography (CT) findings. Intermediate risk was determined based on the presence of positive troponin and\or evidence of right ventricular loading upon either CT or 2D echocardiography.

Results: Of the 144 patients 34 (24%) sustained the primary EP and 8 (6%) died. Patients sustaining the primary EP were twice more likely to present with syncope (29%vs.14%, p=0.03) and more likely to demonstrate T-waves inversion in leads V1-4 on admission ECG (56%vs.36%, p=0.04). Occurrence of the primary EP was also associated with higher D-Dimer levels (8183±13032 vs. 3673±6846, p=0.015), higher RV\LV volume ratio (3.5±1.6vs.2.6±1.3, p=0.03) and contrast media reflux to the inferior vena cava (IVC) (100%vs.69%, p=0.02) on admission CT and severe reduction in RV function upon 2D echocardiography (41%vs.15%, p=0.02).

Using multi-variate analysis, IVC reflux on CT (OR-8.6 95% CI 1.7-45), T-waves inversion in V1-4 (OR-5.1, 95% CI 1.6-16), and D-Dimer (OR-1.1 95% CI 1-1.3) remained significant predictors of the primary EP. Interestingly, when patients were further stratified as suggested by the ESC guidelines to either intermediate-low (either positive troponin or RV loading, N=47) or intermediate-high (both parameters, N=97), there were no differences in the primary EP (17%vs.27%, p=0.2) or mortality (4.3%vs.6.7%, p=0.7).

Conclusions: In patients with intermediate risk PE, electrocardiographic, laboratory and CT findings can predict the need for escalation therapy and therefore may help guiding therapy.