On<unk> PA, the pulmonary vessels are filled with contrast, and appear white. Any mass filling defects (embolus or other matter such as fat) appears darker. Ideally, the scan should be complete before the contrast reaches the left side of the heart and the aorta, as this may mean contrast has drained from the pulmonary arteries, or require a larger dose of contrast media. Other from assessing any filing defect within the pulmonary trunk and its segmental branches, the diameter of the right heart can be compared with diameter of the left heart. The right heart diameter should not be more than the diameter of left heart. Normlly, the interventricular septum should midly buldge into the right ventricle due to high pressure within the left ventricle. Any reverse buldge or flattening of the interventricular septum indicates pulmonary hypertension. Pericardial effusion may also be seen in pulmonary hypertension. Thickening of pericardium more than 4 mm or pericardial calcification indicates constrictive pericarditis.
CT pulmonary angiogram
Pulmonary angiography
Fractional flow reserve
Carbon dioxide angiography
Intravascular imaging
Lung biopsy
Coronary catheterization
Thoracoscopy