Backgrounds: We tried to evaluate several 2D Doppler echocardiographic and pulmonary CT angiographic indices as well as biomarkers, for whether they are related to the prognosis of acute pulmonary thromboembolism (APTE). Methods: We consecutively included 300 patients who had been hospitalized with APTE in a single center from 1998 to 2008. These patients were classified into 2 groups; provoked and unprovoked, based on whether the patients had had risk factors of APTE. Patients were assessed by echocardiograhic indices such as right ventricular end-diastolic dimension/left ventricular end-diastolic dimension (RVEDD/LVEDD), RVEDD, right ventricular systolic pressure(RVSP), and TR Vmax or by CT indices such as right ventricular dimension and left ventricular dimension (RVD/LVD) ratio, pulmonary artery/aorta ratio (PA/Ao ratio), and CT clot burden score (CB score) by Qanadli were measured in each patients. Baseline characteristics, laboratory values, echocardiogram and CT indices were evaluated by univariate analysis and multivariate logistic regression analysis were performed to assess the association with 30 day mortality. Results: The numbers of patients (mean age, 63.6 짹 15.0 years) in provoked and unprovoked group were 167 (55.7%) and 133 (44.3%), respectively. Mean follow-up period was 25.4 months. Of those, 168 patients were available CT assessment for APTE. Mean CT RVD/LVD ratio was 1.276 짹0.50, Mean PA/Ao was 0.909 짹0.21, mean Clot score by Qanadli was 14.77짹 7.33. After univariate analysis, CT RVD/LVD ratio and D-dimer was stastically important. Multivariate logistic regression analysis showed CT RVD/LVD ratio is a significantly associated with 30 day mortality in APTE. Conclusions: CT RVD/LVD ratio is a significant clinical predictor of 30 day mortality in provoked APTE