• CPET
• CTEPD
• echo
• ESE
• lung scan
• RV dysfunction

Background and Aim: Chronic thromboembolic pulmonary disease (CTEPD) is characterized by persistent perfusion defects and progressive pulmonary vascular dysfunction after acute pulmonary embolism (PE), despite adequate anticoagulant therapy. This study aimed to assess the long-term clinical, hemodynamic, and functional evolution of patients with persistent lung perfusion scintigraphy (Q-scan) defects and to identify non-invasive predictors of right ventricular (RV) impairment and exercise-induced pulmonary hypertension (ExPH).
Methods: We analyzed 55 patients with a history of PE and no prior cardiopulmonary disease, stratified by Q-scan at 4 months into Q-scan positive (n=35) and Q-scan negative (n=20) groups. At 4 months, all patients underwent echocardiography, cardiopulmonary exercise testing (CPET), and exercise stress echocardiography (ESE). Clinical evaluation and resting echocardiography were then repeated at 24, 36, and 48 months.
Results: At baseline, the Q-positive group had higher NT-proBNP levels and greater PESI scores. At 4 months, they exhibited a higher prevalence of exercise-induced pulmonary hypertension (ExPH) on both CPET and ESE (p<0.001). Over time, echocardiographic parameters showed partial recovery in both groups; however, Q-positive patients maintained significantly altered values at 48 months, including elevated sPAP and mPAP, reduced TAPSE/sPAP ratio (p<0.001), increased eccentricity index, and shorter RVOT acceleration time. These findings reflect persistent RV-pulmonary arterial uncoupling and suggest subclinical hemodynamic burden.
Conclusions: Persistent Q-scan defects identify a post-PE population at risk of long-term RV dysfunction and ExPH, even in the absence of pulmonary hypertension at rest. CPET and ESE performed at 4 months provide useful prognostic information, supporting their integration into structured follow-up strategies for early identification of patients with evolving pulmonary vascular disease.
Keywords: Chronic thromboembolic pulmonary disease; Q-scan; right ventricular dysfunction; exercise-induced pulmonary hypertension; cardio-pulmonary exercise test; CPET; ESE; echocardiography; cardiovascular risk.