CT scan findings in chronic thromboembolic pulmonary hypertension: predictors of hemodynamic improvement after pulmonary thromboendarterectomy

STUDY OBJECTIVES: The aim was to correlate CT scan findings with hemodynamic measurements in patients who had undergone pulmonary thromboendarterectomy (PTE) and to evaluate whether CT scan findings can help to predict surgical outcome.Patients and method: Sixty patients who underwent PTE and preoperative helical CT scanning were included. Preoperative and postoperative hemodynamics were correlated with preoperative CT imaging features. RESULTS: The diameter of the main pulmonary artery (PA) and the ratio of the PA and the diameter of the ascending aorta correlated with preoperative mean pulmonary artery pressure (PAP) r = 0.42; p < 0.001; and r = 0.48; p < 0.0001, respectively]. There was a significant correlation of subpleural densities with preoperative pulmonary vascular resistance (PVR) r = 0.44; p < 0.001] and of the number of abnormal perfused lobes with preoperative PAP (r = 0.66; p < 0.0001) and PVR (r = 0.76; p < 0.0001). Postoperative PVR correlated negatively with the presence and extent of central thrombi (r = -0.36; p = 0.007) and dilated bronchial arteries (p = 0.03) seen on preoperative CT scans. Sixty percent of patients (3 of 5 patients) without visible central thromboembolic material on CT scans had an inadequate hemodynamic improvement in contrast to 4% of patients (2 of 51 patients) with central thrombi (p = 0.003). Preoperative PVR (r = 0.31; p = 0.018) and the extent of abnormal lung perfusion (r = 0.37; p = 0.007) and of subpleural densities (r = 0.32; p = 0.017) were positively correlated with postoperative PVR. CONCLUSIONS: In patients with thromboembolic pulmonary hypertension, CT scan findings can help to predict hemodynamic improvement after PTE. The absence of central thrombi is a significant risk factor for inadequate hemodynamic improvement.