QTc Prolongation as a Diagnostic Clue in Acute Pulmonary Embolism

Background: Pulmonary embolism (PE) increases right ventricular (RV) afterload, potentially leading to myocardial stress and electrocardiographic abnormalities. Although QTc prolongation has been suggested as a marker of RV dysfunction, its prevalence, clinical significance, and prognostic value in acute PE remain poorly defined. Objective: The objective of this study is to evaluate the prevalence and clinical implications of QTc prolongation in patients with intermediate-high and high-risk acute PE. Methods: We retrospectively analyzed 95 consecutive patients admitted with intermediate-high or high-risk PE between September 2021 and December 2023. QTc prolongation was defined as ≥470 ms in males and ≥480 ms in females. Clinical, imaging, and laboratory data were compared between patients with normal and prolonged QTc intervals. QTc was assessed at admission, after treatment, and prior to discharge. Results: QTc prolongation was observed in 28.4% of patients at presentation. This group had significantly higher lactate levels (2.3 vs. 1.8 mmol/L, p = 0.03) and a non-significant trend toward elevated troponin and lower oxygen saturation. No differences were observed in echocardiographic or CT-based RV dysfunction parameters. QTc values normalized by discharge irrespective of treatment modality. There was no association between QTc prolongation and in-hospital or long-term mortality. A trend toward more aspiration thrombectomy was noted in the prolonged QTc group (29.6% vs. 11.8%, p = 0.06). Conclusions: QTc prolongation is common in acute intermediate-high and high-risk PE and may reflect transient myocardial stress. While not predictive of clinical outcomes, it should be considered in the differential diagnosis of QTc prolongation in patients presenting with dyspnea and chest pain.