Descriptive patterns of severe chronic pulmonary hypertension by chest radiography.

Background: To find chest roentgenographic (CXR) features to help differentiate two representative diseases with severe chronic pulmonary hypertension (PH).

Study Subjects: Thirty-six consecutive patients with chronic thromboembolic PH (CTEPH), 38 with primary PH (PPH), and 37 with left heart disease and PH.

Methods: CXRs were reviewed about 6 features (left 2nd arc protrusion, right descending pulmonary artery diameter (rPAD), cardiothoracic ratio (CTR), right 2nd arc width, avascular area and pleural abnormality). Hemodynamic data and the degree of tricuspid regurgitation (TR) on echocardiography were compared with CXR findings.

Results: The diagnostic pattern of CTEPH was the presence of one of two findings, an avascular area or marked rPAD (>20mm) together with pleuritic change. The diagnostic pattern of PPH was one of the two features; without pleuritic abnormality, marked left 2nd arc protrusion (>10mm) or moderate left 2nd arc protrusion (5-10mm) with marked rPAD (<20mm). The sensitivity for the diagnosis of CTEPH among the three diseases was 78% and specificity was 92%. The sensitivity for the diagnosis of PPH was 45% and specificity was 88%. CTR and right 2nd arc width were related to the degree of TR in CTEPH and PPH.

Conclusions: Characteristic roentgenographic findings can help differentiate two frequent diseases associated with chronic pulmonary hypertension and reflect the severity of disease.