Update in prognostic stratification in patients with pulmonary embolism at intermediate-high risk, a sub-analysis of the USAT IH-PE registry

pulmonary embolism (PE) is the third leading cause of death from cardiovascular disease. While treatment strategies are well defined for high-risk and low-risk patients, the intermediate-high risk group remains a grey zone, with mortality ranging from 3 to 12%. In this population, identifying additional predictors of adeverse outcomes is crucial to promptly select patients who may benefit from early reperfusion strategies beyond heparine alone.

the aim of this sub-analysis is to identify early prognosticators at Emergency Department (ED) presentation that are not included in the ESC classification, in order to enhance stratification of intermediate-high risk patients.

we performed a retrospective study of patients treated with ultrasoud-faciltated catheter directed thrombolysis from march 2018 to november 2024. Data were extracted from ongoing retrospective and prospective multicenter registry, the USAT IH-PE registry. The primary outcome was a composite of intra-hospital mortality, Bleeding Academic Research Consortium (BARC) 3 or pulmonary artery systolic pressure (PASP) >40 mmHg.

we included 173 patients with intermediate-high risk PE. The majority were female (52%), with a mean age of 66 (55-74) years old. A 7.4% of patients had a previous episode of pulmonary thromboembolism, 24% had a history of previous or current neoplasia, 11% were affected by chronic kidney disease and most were overweight or obese. There were 50 primary events. Syncope at presentation or National Early Warning Score 2 (NEWS2) ≥5 was associated with increased occurrence of the primary composite outcome (OR 3, 95% CI 1.37-6.57, p = 0.005). Adding lactate assessment increase the association (OR 4.2, 95% CI 1.74-10.25, p = 0.002). Syncope and NEWS2 ≥5 alone were not predictive. Only a level of lactates >2.36 mmol/L alone was associated with the composite outcome (OR 3.17, 95% CI 1.40-7.22, p = 0.005). The AUC of the ROC curve was 0.59 and the optimal cutoff for lactate was 2.36 mmol/L, corresponding to 44.7% sensitivity and 79.7% specificity. The multivariable logistic regression analysis using the three risk factors confirmed that only lactate remain an indipendent prognostic factor.

lactate levels measured at ED admission are a key prognostic marker for identifyng patients with poorer outcomes. Their integration into the ESC risk score allows more accurate stratification of patients with intermediate-high risk PE. Syncope and clinical scores such as NEWS2 ≥5 may further support risk assessment, although they are not found to be standalone predictors. Randomized studies are warranted to validate and sistematically incorporate these markers into clinical guidelines.

ROC curve LAC vs composite outcomes