Computed tomographic pulmonary angiography and prognostic significance in patients with acute pulmonary embolism

Abstract

Background: Patients with acute pulmonary embolism (APE) present with a broad spectrum of prognoses. Computed tomographic pulmonary angiography (CTPA) has progressively been established as a first line test in the APE diagnostic algorithm, but estimation of short term prognosis by this method remains to be explored. Methods: Eighty two patients admitted with APE were divided into three groups according to their clinical presentation: pulmonary infarction (n = 21), prominent dyspnoea (n = 29), and circulatory failure (n = 32). CTPA studies included assessment of both pulmonary obstruction index and right heart overload. Haemodynamic evaluation was based on systolic aortic blood pressure, heart rate, and systolic pulmonary arterial pressure obtained non-invasively by echocardiography at the time of diagnosis of pulmonary embolism. Results: The mortality rate was 0%, 13.8% and 25% in the three groups, respectively. Neither the pulmonary obstruction index nor the pulmonary artery pressure could predict patient outcome. In contrast, a significant correlation with mortality was found using the systolic blood pressure (p,0.001) and heart rate (p,0.05), as well as from imaging parameters including right to left ventricle minor axis ratio (p,0.005), proximal superior vena cava diameter (p,0.001), azygos vein diameter (p,0.001), and presence of contrast regurgitation into the inferior vena cava (p = 0.001). Analysis from logistic regression aimed at testing for mortality prediction revealed true reclassification of 89% using radiological variables. Conclusion: These results suggest that CTPA quantification of right ventricular strain is an accurate predictor of in-hospital death related to pulmonary embolism.

One-shot diagnostic and prognostic assessment in intermediate- to high-risk acute pulmonary embolism: The role of multidetector computed tomography

“…Although there is some evidence that reconstructed four-chamber views may be superior to axial views for the identification of high-risk patients, 19 several studies have found robust prognostic value using standard axial acquisitions to calculate the RV/LV ratio. 11,12,20 In a large retrospective series of 431 patients, 30-day mortality was 15.6% in patients with RV enlargement (reconstructed four-chamber views), defined as RV/LV ratio >0.9 on MDCT, compared to 7.7% in those without this finding. 6 In the above-mentioned meta-analysis of two studies (with two different RV/LV ratio thresholds, 1.5 and 1.0) including 191 normotensive patients with PE, a 58% (95% CI, 51---65%) overall negative and a 57% positive (95% CI, 49---64%) value of RV dilatation were reported on MDCT for predicting early death, yielding a relative risk for in-hospital mortality of 2.28 (95% CI, 0.9---5.9).…”

“…Moreover, most studies only include patients with less severe forms of PE, a fact that is highlighted by the low arterial obstruction and RV/LV indices reported. 5,11,12 Two studies focused only on MDCT findings in massive PE, using different definitions. Ocak et al studied three patients with massive PE and concluded that reduced left atrial and pulmonary vein diameters were important findings on MDCT.…”

“…This is reflected by the low mean RV/LV ratios reported in the literature, ranging from 1.1 5,11 to 1.32. 12,13 Moreover, the proportion of patients undergoing thrombolytic therapy in these studies was also low.…”

Elevated gamma glutamyl transferase levels are associated with the location of acute pulmonary embolism. Cross-sectional evaluation in hospital setting

“…21 In risk classification, detection of proximal extension in pulmonary embolism patients is a prognostic factor with unrecognized value. 5 The cardiac biomarkers troponin and natriuretic peptide have emerged as promising tools for evaluating the risk among patients diagnosed with APE.…”

Subjective assessment of right ventricle enlargement from computed tomography pulmonary angiography images

“…In a quest to evolve CT's competence beyond a pure as-is state interpretation into a tool for prognosis, applying the concept of evaluating the size and function of the right ventricle (RV) for risk assessment has been studied [16][17][18]. Initiated by the study of Reid et al, various studies compared right-ventricular measurements and ratios of right-ventricular diameters to left-ventricular (LV) diameters in a variety of image reconstructions, from true 4-chamber views to axial images [19][20][21][22][23]. Besides one-dimensional measurements, volumetric assessment of the right ventricle, although more timeconsuming, has been shown to be superior in the identification of high-risk patients [24].…”