• CTEPD; CTEPH; ESE; CPET; ExPH

Chronic thromboembolic pulmonary disease (CTEPD) is a progressive clinical entity caused by wall-adherent, fibrotic thrombi and vascular remodeling in the pulmonary circulation despite prolonged anticoagulation. We evaluated clinical factors predictive of CTEPD, as well as its impact on functional capacity, pulmonary hemodynamics at rest and after exercise, and right ventricle (RV) morphology and function.
We compared 33 consecutive patients with a history of acute pulmonary embolism and either normal pulmonary vascular imaging (negative Q-scan, group 1, n=16) or persistent defects on lung perfusion scan (positive Q-scan) despite oral anticoagulation at 4 months (group 2, n=17). Investigations included thrombotic load on computed tomography angiography, the Pulmonary Embolism Severity Index (PESI) score, World Health Organization functional class (WHO-FC), N-terminal prohormone of brain natriuretic peptide (NT-proBNP), cardiopulmonary exercise test (CPET) and echocardiography parameters at rest and after exercise (ESE), at 4 and at 24 months.
Compared with group 1, group 2 featured a higher PESI score (p=0.02) and a higher thrombotic load (p=0.004) at hospital admission. At 4 months, group 2 developed exercise-induced pulmonary hypertension (Ex-PH) at CPET (p<0.001) and ESE (p<0.001). At 24 months group 2 showed higher NT-proBNP (p<0.001) and WHO-FC (p<0.001), systolic (p<0.001) and diastolic (p=0.037) RV dysfunction and worse RV-arterial coupling (p<0.001) despite maintaining a low or intermediate echocardiographic probability of PH.
Conclusions: Patients with positive Q-scan frequently develop Ex-PH and RV functional deterioration as well as reduced functional capacity. Ex-PH predicts the progression to CTEPD.