Echocardiography in the diagnostic and prognostic evaluation of thromboembolic pulmonary hypertension

Pulmonary arterial hypertension frequently develops after a thromboembolic pulmonary event. The difference in degree of pulmonary artery pressure depends mainly on the size and location of the pulmonary embolus and presence of pre-existing cardiopulmonary diseases. Right ventricle (RV) afterloading from an acute obstruction of the pulmonary vasculature causes an increase of RV volume and dysfunction of right heart cavities, the varying levels of severity of which explain the multiple clinical expression of pulmonary embolism (PE). While the diagnostic approach, therapeutic management and prognostic evaluation are now well defined, the natural progression of PE is still not completely understood. In particular, insufficient data exist on the rate, timing and modalities of development of chronic thromboembolic pulmonary hypertension (CTPH). The aim of this review is to evaluate the role of echocardiography in detecting patients with CTPH, and in assessing hemodynamic consequences on RV and related prognostic implications.