Pulmonary hypertension in idiopathic pulmonary fibrosis: Utility of HRCT

The development of Pulmonary Hypertension (PH) in patients with Idiopathic Pulmonary Fibrosis (IPF) increase the risk of death. An early diagnosis is important to better manage the patients treatment. Our purpose was to evaluate the reliability of HRCT-parameters suggesting PH in a population of IPF-patients with or without PH at the right-sided-heart-catheterization. A radiologist (with a 10-years-experience) and a radiology resident evaluated the HRCT of 29 patients with IPF, underwent RHC and echocardiography. 15 out of 29 patients had PH at RHC. The HRCT parameters related to the mean pulmonary artery pressure (mPAP) were: the PA-area, the ratio of the PA-area to the ascending aorta diameter and above all the ratio of the diameter of segmental artery to the adjacent bronchus in the left upper lobe (R2=0,354973; p=0,0006). The combination of systolic pulmonary artery pressure (sPAP), the PA-area at HRCT and the ratio of the diameter of segmental artery to the adjacent bronchus in the apicoposterior segment of the left upper lobe was strongly correlated to mPAP (R2=0,785163; p=0,0001). Using the ROC Analysis we found that 931,6 is the upper limit of normal (ULN) for the PA-area, with a 86% sensitivity and 61% specificity (0,839 AUC); while 20,34 is the ULN for the ratio of the PA-area to the ascending aorta diameter, with a 100% sensitivity and 50% specificity (0,804 AUC). HRCT seems to remain an useful tool in identifying patients with PH, the combination of HRCT and echocardiograpy could improves accuracy in PH diagnosis.