Diagnostic Performance of Quantitative Computed Tomography Pulmonary Angiography Parameters in Patients With Pulmonary Embolism

To investigate the prognostic value of an integrative approach combining clinical variables and the Qanadli CT obstruction index (CTOI) in patients with nonmassive acute pulmonary embolism (PE). This retrospective study included 705 consecutive patients (mean age, 63 years; range, 18-95 years) with proven PE. Clot burden was quantified using the CTOI, which reflects the ratio of fully or partially obstructed pulmonary arteries to normal arteries. Patients were subdivided into two groups according to the presence (group A) or absence (group B) of preexisting cardiopulmonary disease. Thirty-day and 3-month mortality was evaluated. CTOI thresholds of 20% and 40% were used to stratify patients regarding outcome (low, intermediate, and high risk). The predictive value of CTOI was assessed through logistic regression analysis. Analysis included 690 patients (mean age, 63.3 years ± 18 [standard deviation]) with complete follow-up data: 247 (36%) in group A and 443 (64%) in group B. The mean CTOI was 23% ± 19, 30-day mortality was 9.7%, and 3-month mortality was 11.6%. Three-month mortality was higher in group A than in group B (17.8% and 8.1%, respectively; P = .001). Within group B, CTOI predicted outcome and allowed stratification: significantly higher mortality with CTOI greater than 40% (P < .001) and lower mortality with CTOI less than 20% (P = .05). CTOI did not predict outcome in group A. Age was an independent mortality risk factor (P ≤ .04). CTOI predicted outcome in this cohort of patients with PE and no cardiopulmonary disease, and it may provide a simple single-examination-based approach for risk stratification in this subset of patients.© RSNA, 2020See also the commentary by Kay and Abbara in this issue.

IntroductionMDCT pulmonary angiography is the method of choice for the detection of pulmonary embolism (PE). The severity of PE as estimated by the obstruction index (OI) and right ventricular dysfunction (RVD) can be evaluated with MDCT. ObjectiveTo investigate the correlation between the OI, RVD and clinical presentation in patients with acute PE. MethodsAmong 70 patients with suspected PE, 35 patients proved to have PE with MDCT. The CT OI and the RV/LV diameter (RVD-ratio) using the four-chamber view of the heart were calculated for PE patients. The cut-off for the OI to detect RVD was constructed using ROC curve. ResultsDyspnea and RVD (RVD-ratio >1) were significantly more common in patients with central pulmonary emboli. The mean OI (35%±19%) was significantly higher in patients with dyspnea, tachycardia and obesity. A positive correlation was found between the OI and both the CT pulmonary artery diameter (r=0.66, p<0.001) and the RVD-ratio (r=0.628, p<0.001). The mean OI was significantly higher in patients with RVD (p<0.001). A CT OI>43% identified more than 90% of patients with RVD (area under the curve on ROC analysis: 0.825; p<0.001). ConclusionThe mean OI correlated linearly with PA diameter and RVD-ratio. OI>43% proved to be an independent predictor of RVD.

Importance of computed tomography pulmonary angiography for predict 30-day mortality in acute pulmonary embolism patients

Background Right ventricle (RV) dysfunction at echocardiography is a recognized predictor of death or clinical deterioration in patients with acute pulmonary embolism (PE). However, the best predictor of death among echo parameters of RV dysfunction is unknown. Purpose This meta-analysis is aimed at assessing the role of individual parameter of RV dysfunction at echocardiography to predict all-cause short-term death in patients with acute PE. Methods OVID was searched between 1993 and January 2020 for studies i) including patients with confirmed acute PE; ii) reporting on RV assessment at echocardiography at admission; iii) reporting on short-term all-cause or PE-related death. The primary study outcome is short-term (30 days or in-hospital) all-cause mortality. Results We report here on the role of tricuspid annular plane excursion (TAPSE) and right-to-left ventricle diameter ratio (RV/LV) at echocardiography as predictors of short-term death in patients with acute PE. TAPSE. Abnormal TAPSE at echocardiography was associated with increased risk for short-term death in all-comers with acute PE (eight studies; 3298 patients; RR 2.78 CI 95% 0.53–14.63; Figure 1) and in hemodynamically stable patients (six studies; 3013 patients; RR 2.76 CI 95% 1.44–5.30 I2 58%). The association is confirmed for different cut-off values of TAPSE (≥15mm or any cut-off value &amp;gt;15mm). RV/LV. In eight studies reporting on continuous measures, the difference between mean right and left ventricle diameter at echocardiography in patients who died vs those who survived ranged from 0.02 to 0.3 mm. Abnormal RV/LV ratio at echocardiography was not associated with increased risk for short-term death in all-comers with acute PE (six studies; 2292 patients; RR 1.48 CI 95% 0.43–5.08), nor in hemodynamically stable patients (four studies; 1014 patients; RR 1.20 CI 95% 0.72–1.99, I2=0%). Conclusion Abnormal TAPSE is associated with short-term death in patients with acute PE. In these patients, the prognostic role of RV/LV diameter ratio as stand-alone parameter of RV dysfunction at echocardiography remains unclear. Funding Acknowledgement Type of funding sources: None. Figure 1. Association between TAPSE and all-cause

Objectives: Acute pulmonary embolism (PE) is a common disease, necessitating risk stratification to determine management. A right ventricle (RV) to left ventricle (LV) diameter ratio ≥1.0 on computed tomography pulmonary angiography (CTPA) suggests RV strain, which may indicate a worse prognosis. Two prior studies showed that residents with brief training by a radiologist could accurately measure RV/LV ratio. We assessed whether medical students could accurately measure RV dilatation. Methods: We conducted a post hoc analysis of a retrospective cohort study of adults undergoing management for acute PE at 21 community emergency departments across Kaiser Permanente Northern California from 2013 to 2015. We created a sample, stratified to contain an equal number of patients from each of the 5 PE Severity Index classes. Four medical students measured RV and LV diameter on CTPA after training from an emergency medicine physician and an interventional radiologist. We used Cohen's kappa statistics, Bland-Altman plots, and Pearson correlation coefficients to assess interrater reliability. Results: Of the 108 CTPAs reviewed, 79 (73%) showed RV dilatation and 29 (27%) did not. The kappa statistic for the presence of RV dilatation of the medical students compared to the radiologist showed moderate agreement for 3 medical students (kappa (95% CI): 0.46 (0.21-0.70), 0.49 (0.31-0.68), 0.50 (0.32-0.68)) and fair agreement for 1 medical student (kappa (95% CI): 0.29 (0.10-0.47)). The average interrater differences in RV/LV ratio between a radiologist and each of the 4 medical students were −0.04, −0.05, 0.04, and 0.24. Pearson correlation coefficients were 0.87, 0.80, 0.74, and 0.78, respectively, indicating moderate correlation (P < .001 for all). Conclusion: Medical students were able to identify RV dilatation on CTPA in moderate agreement with that of a radiologist. Further study is needed to determine whether medical student accuracy could improve with additional training.

Background The Qanadli index can be used to assess the severity of pulmonary arterial involvement in patients with acute pulmonary embolism. However, it seems that considering pulmonary infarction and right ventricle/left ventricle (RV/LV) ratio along with this index (called the combined Qanadli index) can provide a more accurate view of changes in cardiovascular parameters in these patients and help predict mortality in a better manner. In this regard, we evaluated the ability of the combined Qanadli index versus the Qanadli index in predicting short-term mortality in patients with pulmonary embolism. Methods This retrospective study enrolled 234 patients with acute pulmonary embolism. Patients were divided into two groups: those who expired in 30 days and who survived. Then they were evaluated by computed tomography angiography of pulmonary arteries. The RV/LV diameter ratio and also pulmonary artery obstruction index (PAOI) were calculated. The patient's computed tomography scans were reviewed for pulmonary infarction. By adding the RV/LV ratio and pulmonary infarction to PAOI, a new index called the modified Qanadli score was made. Univariable and multivariable logistic regression was done for finding predictors of mortality. Results Nine cases (40%) of patients in the mortality group and 42 (20%) of survivors had ischemic heart disease and the difference was significantly meaningful. The mean Qanadli index in the mortality group was 16.8 ± 8.45 and in survivors was 8.3 ± 4.2. By adding the pulmonary infarction score and PAOI score to RV/LV ratio score, the odds ratio (OR) for predicting mortality increased significantly to 13 and 16, respectively, which were significantly meaningful. Based on our findings, the highest OR for predicting short-term mortality was obtained through a combined Qanadli index (PAOI score + pulmonary infarction score + RV/LV score) that was 17 in univariable and 18 in multivariable logistic regression analysis ( p -value = 0.015). Conclusion The new combined Qanadli index has more ability than the Qanadli index and RV/LV ratio for predicting changes in cardiovascular parameters and short-term mortality in patients with pulmonary embolism.

Pulmonary embolism is a serious and potentially fatal disorder. Pulmonary embolism risk stratification may allow early hospital discharge and outpatient treatment for low-risk patients. Also, it may prevent death by early medical intervention in high-risk groups. We evaluated objectively confirmed pulmonary embolism in 126 patients by multidetector computed tomographic pulmonary angiography at a single center from January 2008 to January 2010. The Pulmonary Severity Embolism Index (PESI), the right ventricle (RV) to left ventricle (LV) diameter (RV/LV) ratio and the vascular obstruction index (VOI) were derived from data extracted from electronic hospital records and image database. A total of six out of 96 patients (6.3%) died during follow-up. There was an association between PESI and mortality (P-value < 0.001 χ² test). PESI class I-II had a 100% negative predictive value for death in 90 days. No association was found between the RV/LV ratio, the VOI and mortality (P-value > 0.05 χ² test). Also, no association was found between the RV/LV ratio and the VOI and PESI (P-value > 0.05 χ² test). PESI is an accurate tool for pulmonary embolism prognostic stratification. It safely discriminates low-risk from high-risk patients regarding death outcome. We were unable to demonstrate an association between image scores and mortality.

Evaluation of right atrium-to-right ventricle diameter ratio on computed tomography pulmonary angiography: Prediction of adverse outcome and 30-day mortality

Background/Aim: Venous thromboembolism is a pathological process that is among the leading causes of hospital mortality, and many studies showed that vitamin D receptors have a role in thrombosis. This study aimed to investigate the effect of 25(OH)D deficiency on pulmonary thromboembolism and evaluate the pulmonary embolism severity index (PESI). Methods: Eighty-one patients over 18 years of age who underwent CT angiography with a pre-diagnosis of pulmonary embolism were included in this case-control study. Groups 1 and 2 consisted of 45 patients with pulmonary embolism (PE), and 36 patients without pulmonary embolism, respectively. The PE patients were divided into five groups in terms of age, gender, fever, systolic blood pressure, heart rate, respiratory rate, oxygen saturation, history of chronic lung disease and heart failure, mental status, and malignancy to calculate the PESI score. Classes 1 and 2 were classified as low-risk, and Classes 3, 4, and 5 as high-risk. The CT obstruction index (CTOI) was calculated in patients with pulmonary embolism. Vitamin D levels were noted. Results: No significant difference was observed between the groups in terms of age, gender, and body mass index values (P>0.05). 25(OH)D level was significantly lower in the pulmonary embolism group (7.2(3.3) vs. 8.7(7.0), P=0.028). The CTOI was significantly higher in the high-risk patient group (P=0.019). Conclusions: The evaluation of 25(OH)D levels may be beneficial in determining the risk of thromboembolism.

To determine if CT variables predict in-hospital morbidity and mortality in patients with pulmonary embolism (PE). CT scans and charts of 173 patients with CT scans positive for PE were reviewed. CT scans were reviewed for leftward ventricular septal bowing, increased right ventricle (RV) to left ventricle (LV) diameter ratio, clot burden, increased pulmonary artery to aorta diameter ratio, and oligemia. Charts were reviewed for severe morbidity and mortality outcomes: death from pulmonary emboli or any cause, and cardiac arrest. Charts were also reviewed for milder morbidity outcomes: intubation, vasopressor use, or admission to an intensive care unit (ICU) and for multiple comorbidities. No CT predictor was significantly associated with severe morbidity or mortality outcomes. Ventricular septal bowing and increased RV/LV diameter ratio were both associated with subsequent admission to an ICU (P = 0.004 and P = 0.025, respectively). Oligemia (either lung) was associated with subsequent intubation; right lung oligemia was associated with the subsequent use of vasopressors. After controlling for history of congestive heart failure, ischemic heart disease, and pulmonary disease, both septal bowing and an increased RV/LV diameter ratio remained associated with admission to an ICU. No CT variables predicted severe in-hospital morbidity and mortality (death from pulmonary embolism, death from any cause, or cardiac arrest) in patients with PE. However, ventricular septal bowing and increased RV/LV diameter ratio were both strongly predictive of less severe morbidity, namely, subsequent ICU admission, and oligemia was associated with subsequent intubation and vasopressor use.

This study was designed to define and evaluate a specific index to quantify arterial obstruction with helical CT in acute pulmonary embolism. Fifty-four patients (mean age, 56 years) with proven pulmonary emboli among 158 consecutive patients, who had undergone both CT and pulmonary angiography for clinically suspected pulmonary embolism, were eligible for the study. The CT obstruction index was defined as (n. d) (n, value of the proximal clot site, equal to the number of segmental branches arising distally; d, degree of obstruction scored as partial obstruction [value of 1] or total obstruction [value of 2]). We compared the CT obstruction index with pulmonary arterial obstruction on angiography (assessed by the Miller index), using linear regression, and correlated it with findings on echocardiography. Interobserver variability was determined for both CT and pulmonary angiography indexes. The CT obstruction index (29% +/- 17%) and the Miller index (43% +/- 25%) were well correlated (r = 0.867, p < 0.0001) with an excellent concordance between investigators for both the CT index (r = 0.944, p < 0.0001) and the Miller index (r = 0.904, p < 0.0001). A CT obstruction index greater than 40% identified more than 90% of patients with right ventricular dilatation. The degree of arterial obstruction in pulmonary embolism may be quantified by a specific CT index that appears reproducible and highly correlated to the previously described index with pulmonary angiography. Further evaluations are needed to investigate the usefulness of the CT obstruction index for stratification of patient risk and determining therapeutic options.

Introduction In addition to standard echocardiographic measures, global longitudinal strain (GLS) with speckle tracking (ST) and myocardial work (MW) evaluation have been used in the assessment of right ventricle (RV) function in patients with acute pulmonary embolism (PE). In this study we aimed to compare echocardiographic measures, ST and MW in prediction of change in right ventricle (RV) to left ventricle (LV) diameter ratio (r) with treatments. Methods Our study comprised 83 consecutive patients (female %54.6, age 59±14.9 years) who admitted to our hospital with diagnosis of acute PE and underwent evidence-based treatments. Echocardiographic evaluation including ST and MW were performed within first 24 hours of admission. NT-pro-brain natriuretic peptide (NT-proBNP), troponin, pulmonary embolism severity index (PESI) and Qanadli score, RV and LV global work index (GWI), global work efficiency (GWE), global constructive work (GCW) and global wasted work (GWW), and RV-GLS were evaluated. Primary end-point (PEP) of this study was the change in RV to LVr on computed tomography (CT), and generalized additive model (GAM) in addition to classical linear regression (LR) were utilized for prediction of change in RV/LVr with these measures. Results PESI score and RV/LVr at admission were 84.8±23.8 and 1.13±0.39, respectively. Unfractioned or low-molecular weight heparin were treatments of choice in patients. The change in RV/LVr after selected treatments were 0.356. Mean hospital stay and overall follow-up duration were 8.7±3.7 and 328.7±126.8 days, respectively. In-hospital and long-term mortality rates were 1.2% and 13.3% respectively. Correlation co-efficients for intra- and interobserver agreement of MW measures varied from 0.85 to 0.96. The LR revealed that pulmonary arterial systolic, diastolic and mean pressure estimates, fractional area change and RV annular tissue velocity were significantly related with changes in RV/LVr (p values; 0.02, 0.01, 0.004, 0.03 and 0.03, respectively). Moreover, RV-GWE compared with RV-GLS showed a higher prediction for improvements in the RV/LVr (p value were &amp;lt;0.001 and 0.049, respectively). Utilization of GAM increased R2 value (from 0.15 to 0.20), and decreased the complexity of model. RV-GWE showed a moderate correlation with RV-GLS (r=-0.56), RV-GWI (r = 0.42), RV-GCW (r=0.32), LV-GWW(r=-0.55), LV-GLS (r=-0.33), FAC (r=0.26), NT-proBNP (r=-0.38), troponin (r=-0.28) but not with other measures. Conclusions The RV GWE as a novel myocardial work parameter seems to provide a better prediction for improvements in the RV/LVr with acute PE treatments as compared to clinical, laboratory and other echocardiographic measures including GLS.Figure-1Figure-2

Lipoprotein (a) [Lp(a)] is suspected to have antifibrinolytic effects, however, its relevance for the severity of venous thromboembolic events remains unclear. We studied the association of Lp(a) levels with thrombus load in pulmonary embolism (PE). 90 patients (40% female, median age 70 [56–79] years) at our tertiary care hospital with a diagnosis of acute PE, available Lp(a) levels and CT pulmonary angiography (CT-PA) performed between April 2017 and December 2019 were included. All CT-PA scans were reanalyzed and thrombus load was determined via Qanadli CT obstruction index (CTOI) and most proximal thrombus location. Median Lp(a) levels were 11.4 [9.3–29.1] mg/dL, median D-dimer levels were 4.6 [2.1–9.8] mg/L, median CTOI was 23 [8–50], central PE was present in 27 (30%) patients. Lp(a) did not correlate with CTOI (r = 0.02, p = 0.922) and was not associated with thrombus location (p = 0.369). CTOI significantly correlated with D-dimer (r = 0.43, p < 0.001) and right to left ventricular diameter ratio (r=-0.49, p = < 0.001). Our findings showed that Lp(a) is not associated with thrombus burden in PE, which suggests that a relevant effect of Lp(a) on the extent of venous thromboembolism is unlikely.

Serial imaging after pulmonary embolism and correlation with functional limitation at 12 months: Results of the ELOPE Study

CT Signs of Right Ventricular Dysfunction: Prognostic Role in Acute Pulmonary Embolism