Role of 320-slice CT imaging in the diagnostic workup of patients with chronic thromboembolic pulmonary hypertension.

Background: Right-sided heart catheterization (RHC) and pulmonary digital subtraction angiography (PDSA) are the standard methods used in diagnosing suspected or defi nite chronic thromboembolic pulmonary hypertension (CTEPH). We studied the ability of 320-slice CT imaging to detect simultaneously chronic thromboembolic fi ndings in the pulmonary arteries and pulmonary hemodynamics based on the curvature of the interventricular septum (IVS) in CTEPH .
Methods: Forty-four patients with high clinical suspicion of CTEPH underwent RHC, PDSA, and enhanced double-volume retrospective ECG-gated 320-slice CT scan. We measured the sensitivity and specificity of CT imaging to detect thrombi in the pulmonary arteries compared with PDSA. We also compared IVS bowing (expressed as curvature) measured on the short-axis cine heart image with pulmonary arterial pressure (PAP) obtained by RHC.
Results: Compared with PDSA, the sensitivity and specificity of CT imaging to detect chronic thromboembolic findings were 97.0% and 97.1% at the main/lobar level and 85.8% and 94.6% at the segmental level, respectively. The correlation coefficients of IVS curvature with systolic PAP and mean PAP were 2 0.79 ( P , .001) and 2 0.86 ( P , .001), respectively.
Conclusions: The use of 320-slice CT imaging allows for less invasive and simultaneous detection of thrombi and evaluation of pulmonary hemodynamics for the diagnostic work-up of CTEPH.