PURPOSE: To evaluate the role of CT scan and echocardiogram (echo) in detecting pulmonary hypertension in patients evaluated for transplant, using right heart catheterization (RHC) as the gold standard.
METHODS: 450 patients evaluated for lung transplant in BC between 2004 - 2009 were reviewed for presence or absence of PH. Correlation of CT predictors: main pulmonary artery (MPA) diameter greater than 29 mm, MPA to aorta (MPA/AA) ratio greater than 1, and MPA corrected for body surface area (BSA) with RHC determined PH (defined as mean PAP>25 mmHg)as well as echo measured systolic PA pressure greater than 40 mmHg was then sought through construction of scatter plots and calculation of a pearson coefficient.
RESULTS: 47 patients met our inclusion criteria of having investigations within 6 months. Of these, 22 patients had mPAP greater than 25 mmHg on RHC. The mean patient age was 53.8 (SD 12.43) with 20 females. The etiologies of disease mainly included IPF, COPD, CF, and PH. There was no difference in age between patients with and without PH. Initial scatter plots displayed the following: echo sPAP measurements compared to RHC mPAP had a pearson correlation coefficient of 0.75 (p< 0.0001), main PA >29 mm on CT scan compared to RHC mPAP had a coefficient of 0.56 (p< 0.0001), and CT prediction of MPA/Ao diameter >1 had a coefficient of 0.42 (p = 0.004). CT and echo variables were also compared to RHC sPAP with no significant difference from the above results. CT MPA/BSA was also calculated, but unfortunately no current threshold for a significant value has been defined.
CONCLUSION: Echocardiogram is helpful in the prediction of presence/absence of PH in this population. However, CT MPA >29 mm is only a modest predictor. The mean PA of < 29 cannot predict the absence of PH, and the MPA/BSA and mean PA/Ao diameter are not useful.
CLINICAL IMPLICATIONS: Echocardiogram is a reliable test for prediction of PH. However, CT findings used in clinical practice have not shown reliability in this study.
DISCLOSURE: Shalini Nayar, No Financial Disclosure Information; No Product/Research Disclosure Information