Incidence of chronic pulmonary hypertension in patients with previous pulmonary embolism

The true incidence of chronic thromboembolic pulmonary hypertension (CTPH) remains a matter of debate. Symptomatic CTPH is probably more common than previously reported, whereas the occurrence of asymptomatic CTPH has not been defined since very limited evidence on the incidence of asymptomatic CTPH diagnosed with echocardiography Doppler are currently available. We therefore carried out a prospective cohort study to assess the incidence of CTPH diagnosed with echocardiography Doppler in consecutive patients with a first episode of PE.

Consecutive patients with a first episode of PE were evaluated with Doppler transthoracic echocardiography within 6 to 12 months after the index event. Pulmonary hypertension was defined as a systolic pulmonary artery pressure > or =40 mmHg at rest in the presence of residual perfusion defects at perfusion scintigraphy. Presence of symptoms related to pulmonary hypertension was evaluated with a standardized questionnaire.

Ninety-one patients (mean age 61.9+/-15.7 years; range 22-89; 39 men) were enrolled. Eight patients (8.8%; 95% CI 4.5,16.4) had CTPH: of these, 4 (4.4%; 95% CI 2.0, 9.3) were symptomatic.

Asymptomatic CTPH is not an uncommon finding after PE. Larger prospective trials with a longer follow up should assess the prognostic significance of asymptomatic CPTH.