Figure 6.

CT pulmonary angiography features of chronic thromboembolic pulmonary hypertension. Axial image (A) showing reduced caliber vessels (arrows) related to the contraction of the organizing thrombus and poor contrast opacification in comparison with contralateral arteries (arrowheads). Axial maximum intensity projection (MIP) at the thoracoabdominal transition (B) showing a prominent phrenic artery (arrow) providing systemic collateral circulation, in addition to asymmetric caliber of the pulmonary arteries in the lower lobes (attenuated on the right side, arrowheads). Sagittal MIP reconstruction (C) reveals a prominent bronchial artery providing systemic collateral circulation (arrow).