| Chest x ray | May show increase in cardiac chambers, increased pulmonary artery size, hypoperfused areas of lung and evidence of parenchymal lung disease |
| High resolution computed tomography (CT) scan of lungs | May show parenchymal lung disease, mosaic perfusion (a sign of pulmonary vascular embolism or thrombosis but for which there are other causes such as air trapping), and features of pulmonary venous hypertension |
| CT pulmonary angiography | Used to look for enlargement of pulmonary arteries, filling defects and webs in the arteries. Detects enlarged bronchial circulation |
| Ventilation perfusion scanning | More sensitive for chronic pulmonary thromboembolism than CTPA but not helpful when there is underlying parenchymal lung disease |
| Selective pulmonary angiography by direct injection of the pulmonary arteries | Gold standard for delineating chronic pulmonary thromboembolism to define the location and extent of disease. It may be superseded by magnetic resonance angiography or multislice CT. |
| Echocardiography | Screening tool of choice for PH. Detects cardiac disease (congenital, myocardial, valvular, intracavity clot or tumour, pericardial). Use of contrast may be helpful to identify shunts |
| Cardiac magnetic resonance | Good examination for imaging the right ventricle. Helpful in delineating congenital heart defects, and the pulmonary circulation by angiography |
| Abdominal ultrasound | Used for investigation of liver disease and suspected portal hypertension. |