Incidental and Symptomatic Pulmonary Thromboembolism: Clinical Features and Prognostic Comparison

Background Incidental pulmonary thromboembolism (iPTE) is increasingly being detected owing to the widespread use of computed tomography; however, its clinical significance and prognostic impact compared with symptomatic pulmonary thromboembolism (sPTE) remains controversial. Materials and Methods This retrospective observational study included adult patients with acute pulmonary embolism confirmed using CT pulmonary angiography between January 2022 and January 2025. Patients were classified as having iPTE or sPTE based on the clinical presentation and indications for imaging. Demographic characteristics, comorbidities, clinical findings, laboratory parameters, imaging features, and outcomes were compared between groups. Survival was assessed using Kaplan–Meier analysis, and predictors of mortality were evaluated using Cox regression analysis. Results A total of 306 patients were included, of whom 42 (13.7%) had iPTE and 264 (86.3%) had sPTE. Patients with iPTE had a higher prevalence of malignancy and comorbidities, but showed lower heart rate, higher oxygen saturation, lower cardiac biomarker levels, and less right ventricular dysfunction. Radiologically, iPTE was associated with a less extensive embolic burden and fewer parenchymal complications. The median survival did not differ significantly between the iPTE and sPTE groups (log-rank, p = 0.346). In multivariate analysis, malignancy (hazard ratio [HR] 3.07, p < 0.001) and elevated troponin T (HR 2.70, p = 0.002) were independent predictors of mortality, whereas iPTE status was not. Conclusion Despite a lower hemodynamic and radiological burden, incidental pulmonary thromboembolism was associated with survival comparable to that of symptomatic cases. Mortality was primarily driven by underlying malignancy and myocardial injury rather than by embolism presentation. Trial registration Not applicable (retrospective observational study).