Prognostic value of cardiovascular parameters in computed tomography pulmonary angiography in patients with acute pulmonary embolism

Heart lung axis in acute pulmonary embolism: Role of CT in risk stratification

Pulmonary embolism (PE) remains a significant cause of mortality requiring prompt diagnosis and risk stratification. This review focuses on the role of computed tomography (CT) in the risk stratification of acute PE, highlighting its impact on patient management. We will explore basic pathophysiology of pulmonary embolism (PE) and review current guidelines, which will help radiologists interpret images within a broader clinical context. This review covers key CT findings which can be used for risk stratification including indicators of right ventricular (RV) dysfunction, clot burden, clot location and left atrial volume. We will discuss the measurement of RV/LV diameter ratio as a key indicator of RV dysfunction and its limitations and challenges within various patient populations. While these parameters should be included in a radiologist's report, their predictive value for mortality depends on the patient's existing cardiopulmonary reserve and should not be interpreted in isolation.

Prediction of short-term adverse clinical outcomes of acute pulmonary embolism using conventional machine learning and deep Learning based on CTPA images

To explore the predictive value of traditional machine learning (ML) and deep learning (DL) algorithms based on computed tomography pulmonary angiography (CTPA) images for short-term adverse outcomes in patients with acute pulmonary embolism (APE). This retrospective study enrolled 132 patients with APE confirmed by CTPA. Thrombus segmentation and texture feature extraction was performed using 3D-Slicer software. The least absolute shrinkage and selection operator (LASSO) algorithm was used for feature dimensionality reduction and selection, with optimal λ values determined using leave-one-fold cross-validation to identify texture features with non-zero coefficients. ML models (logistic regression, random forest, decision tree, support vector machine) and DL models (ResNet 50 and Vgg 19) were used to construct the prediction models. Model performance was evaluated using receiver operating characteristic (ROC) curves and the area under the curve (AUC). The cohort included 84 patients in the good prognosis group and 48 patients in the poor prognosis group. Univariate and multivariate logistic regression analyses showed that diabetes, RV/LV ≥ 1.0, and Qanadli index form independent risk factors predicting poor prognosis in patients with APE(P < 0.05). A total of 750 texture features were extracted, with 4 key features identified through screening. There was a weak positive correlation between texture features and clinical parameters. ROC curves analysis demonstrated AUC values of 0.85 (0.78-0.92), 0.76 (0.67-0.84), and 0.89 (0.83-0.95) for the clinical, texture feature, and combined models, respectively. In the ML models, the random forest model achieved the highest AUC (0.85), and the support vector machine model achieved the lowest AUC (0.62). And the AUCs for the DL models (ResNet 50 and Vgg 19) were 0.91 (95%CI: 0.90-0.92) and 0.94(95%CI: 0.93-0.95), respectively. Vgg 19 model demonstrated exceptional precision (0.93), recall (0.76), specificity (0.95) and F1 score (0.84). Both ML and DL models based on thrombus texture features from CTPA images demonstrated higher predictive efficacy for short-term adverse outcomes in patients with APE, especially the random forest and Vgg 19 models, potentially assisting clinical management in timely interventions to improve patient prognosis.

Alterations and Significance of Computed Tomography Pulmonary Angiography-Derived Parameters in Older Patients With Acute Pulmonary Embolism

OBJECTIVE

This study aimed to investigate changes of computed tomography pulmonary angiography (CTPA)-derived parameters in older adults with acute pulmonary embolism (APE).

METHODS

According to the pulmonary artery obstruction index (PAOI), patients with APE were divided into the A1 (PAOI ≥30%, n = 57) and A2 (PAOI <30%, n = 40) groups. Participants without APE were placed in group B (n = 170). The left atrial (LA) and left ventricular (LV) parameters among the three groups were compared, and the parameter changes in the 44 patients with APE were analyzed before and after treatment. The correlation between APE severity and the parameters was analyzed using correlation analysis.

RESULTS

The left-to-right diameters (LR) of LA, and LR × anteroposterior diameters (AP) of LA and LV: A1 < A2 < B; LR of LV: A1 < A2, B; AP of LA and LV: A1, A2 < B. After treatment, LR and LR × AP of the LA and LV were significantly increased in the group A1 and LR of the LV and LR × AP of the LA and LV were elevated in the group A2. Acute pulmonary embolism severity was closely associated with LR × AP ( r = -0.557) and LR ( r = -0.477) of LA.

CONCLUSIONS

With an increase in the degree of obstruction, older adults had a smaller LA and LV. Furthermore, the LR and LR × AP values of the LA were significantly decreased. These results contribute to in-time risk stratification.

Saddle pulmonary embolism is not a sign of high-risk deterioration in non-high-risk patients: A propensity score-matched study

BACKGROUND

There is controversy regarding whether saddle main pulmonary artery (MPA) embolism represents a high risk of deterioration in non-high-risk acute pulmonary embolism (PE) patients. This study aims to address this issue by conducting a propensity score matching (PSM) study.

METHODS

A total of 727 non-high-risk acute PE patients were retrospectively evaluated. We evaluated the Bova score and risk stratification to examine the risk of deterioration. Deterioration defined as any adverse event within 30 days after admission. Computed tomographic pulmonary angiography was used to identify the embolism type. All patients were matched into four subgroups by PSM according to age, sex, Bova score, and risk stratification: (1) MPA and non-MPA embolism; (2) non-saddle MPA and non-MPA embolism; (3) saddle MPA and non-saddle MPA embolism; (4) saddle MPA and non-MPA embolism. Correlations were analyzed using Cox regression analysis, and deterioration risk was compared between subgroups using Kaplan-Meier analysis.

RESULTS

Cox regression analysis revealed that MPA embolism was correlated with deterioration, regardless of whether saddle MPA embolism was included or excluded. Saddle MPA embolism was not correlated with deterioration, regardless of comparison with non-saddle MPA embolism or non-MPA embolism. Patients with MPA and non-saddle MPA embolism presented a high risk for deterioration (log-rank test=5.23 and 4.70, P=0.022 and 0.030, respetively), while patients with saddle MPA embolism were not at a high risk of deterioration (log-rank test=1.20 and 3.17, P=0.729 and 0.077, respetively).

CONCLUSIONS

Saddle MPA embolism is not indicative of a high risk of deterioration in non-high-risk acute PE patients.

Rapid prediction of deterioration risk among non-high-risk patients with acute pulmonary embolism at admission: An imaging tool

BACKGROUND

Computed tomography (CT) pulmonary angiography as the first-line diagnosis tool of acute pulmonary embolism (PE), might improve this discriminatory power. We aimed to developed a simply tool combining multi-CT parameters to complete individualized risk assessment of deterioration in non-high-risk patients with acute PE at admission.

METHOD

Consecutive non-high-risk patients with acute PE who were treated in a Chinese center during 2010-2021, were collected.Prognosis-related CT parameters were reviewed. Deterioration was defined as any adverse event within 30 day after admission. Eligible patients were randomized into derivation and validation cohorts. In the derivation cohort, CT parameters were screened for importance using classification tree methodology and enrolled variables was partitioned via curve-fitting and dose-response analysis. A nomogram was developed and the predictive power in both cohorts was evaluated based on the area under the receiver operating characteristic curve (AUROC) and the corresponding 95% confidence interval (CI).

RESULT

A total of 1001 patients were included. The preliminary analyses revealed that deterioration risk was related to the right-to-left ventricular diameter ratio at 4-chamber view, pulmonary vein filling abnormality. After a curve-fitting to deterioration risk, these parameters were partitioned and used to develop a nomogram, which had AUROC values of 0.91 (95% CI: 0.87-0.96) in the derivation cohort and 0.89 (95% CI: 0.81-0.97) in the validation cohort. A web-based version of the radiomics scoring tool was published online for use in clinical practice (https://acutepeprediction.shinyapps.io/Radiomics_Predictive_Tool/).

CONCLUSION

This simply tool can complete rapid estimation of deterioration risk among non-high-risk acute PE patients at admission.

Developing a scoring tool to estimate the risk of deterioration for normotensive patients with acute pulmonary embolism on admission

Background

It is important to identify deterioration in normotensive patients with acute pulmonary embolism (PE). This study aimed to develop a tool for predicting deterioration among normotensive patients with acute PE on admission.

Methods

Clinical, laboratory, and computed tomography parameters were retrospectively collected for normotensive patients with acute PE who were treated at a Chinese center from January 2011 to May 2020 on admission into the hospital. The endpoint of the deterioration was any adverse outcome within 30 days. Eligible patients were randomized 2:1 to derivation and validation cohorts, and a nomogram was developed and validated by the aforementioned cohorts, respectively. The areas under the curves (AUCs) with 95% confidence intervals (CIs) were calculated. A risk-scoring tool for predicting deterioration was applied as a web-based calculator.

Results

The 845 eligible patients (420 men, 425 women) had an average age of 60.05 ± 15.43 years. Adverse outcomes were identified for 81 patients (9.6%). The nomogram for adverse outcomes included heart rate, systolic pressure, N-terminal-pro brain natriuretic peptide, and ventricle/atrial diameter ratios at 4-chamber view, which provided AUC values of 0.925 in the derivation cohort (95% CI 0.900–0.946, p < 0.001) and 0.900 in the validation cohort (95% CI 0.883–0.948, p < 0.001). A risk-scoring tool was published as a web-based calculator (https://gaoyzcmu.shinyapps.io/APE9AD/).

Conclusions

We developed a web-based scoring tool that may help predict deterioration in normotensive patients with acute PE.

Prognostic significance of computed tomography-assessed right ventricular enlargement in low-risk patients with pulmonary embolism: Systematic review and meta-analysis

BACKGROUND

For patients with acute low-risk pulmonary embolism (PE), determined by a validated clinical prognostic score, the additive prognostic significance of computed tomography (CT)-assessed right ventricular (RV) enlargement is uncertain.

METHODS

We performed a systematic review and meta-analysis of studies that enrolled patients with acute low-risk PE to assess the prognostic value of concomitant CT-assessed RV enlargement for 30-day all-cause mortality and PE-related death. We conducted unrestricted searches of PubMed and Embase through December 2019. We used a random-effects model to pool study results; Begg rank correlation method to evaluate for publication bias; and I² testing to assess for heterogeneity.

RESULTS

Of the 7 cohorts with 2197 participants who had low-risk PE and provided results on the primary outcome, 743 (34%; 95% confidence interval [CI], 32-36%) patients had concomitant RV enlargement. Six of 743 (0.8%; 95% CI, 0.3-1.8%) patients with concomitant RV enlargement died 30-days after the diagnosis of PE compared with 3 of 1454 (0.2%, 95% CI, 0-0.6%) without RV enlargement. CT-assessed RV enlargement did not have a significant association with 30-day all-cause mortality (odds ratio [OR], 2.6; 95% CI, 0.7-9.4; I² = 0%; P = 0.15) or PE-related mortality (OR, 2.8; 95% CI, 0.7-12.1; I² = 0%; P = 0.16).

CONCLUSIONS

CT-assessed RV enlargement occurs in a third of PE patients identified as low-risk by clinical scores. Mortality rate in these patients is low, and CT-assessed RV enlargement was not associated with a significantly increased risk of death within 30 days of PE diagnosis.

Correlation of thrombosed vessel location and clot burden score with severity of disease and risk stratification in patients with acute pulmonary embolism

Objective:

Computed tomography pulmonary angiography (CTPA) is used for the main diagnosis in acute pulmonary embolism (APE). Determining the thrombus location in the pulmonary vascular tree is also important for predicting disease severity. This study aimed to analyze the correlation of the thrombus location and the clot burden with the disease severity and the risk stratification in patients with APE.

Methods:

The study included patients with APE diagnosed by CTPA who were admitted to the hospital between January 28, 2016, and July 1, 2019. Data collected were markers of severity in APE, including patient demographics, comorbidities, length of hospital stay, pulmonary embolism severity index (PESI) score, modified PESI score, Wells score, risk stratification according to the American Heart Association, systolic blood pressure (SBP), right ventricle diameter to left ventricle diameter ratio, pulmonary arterial pressure, brain natriuretic peptide, troponin, D-dimer, and plasma lactate levels, and vessel location of the thrombus, clot burden score, ratio of the pulmonary artery trunk diameter/aortic diameter, superior vena cava diameter (SVC) by CTPA, and survival. All parameters were analyzed in correlation with clot load and vessel location.

Results:

Thrombus vascular location was found to be correlated with risk stratification and negatively correlated with SBP. Simplified Mastora score was correlated with risk stratification, SVC diameter, and D-dimer and negatively correlated with SBP. Occlusion of both the pulmonary artery trunk and any pulmonary artery with thrombus was associated with massive APE.

Conclusion:

The level of the occluded vessel on CTPA may provide the ability to risk-stratify, and the clot burden score may be used for assessing both risk stratification and cardiac strain.

Clinical and imaging profiles of pulmonary embolism: a single-institution experience

BACKGROUND

Pulmonary embolism (PE) is a common life-threatening condition with non-specific clinical presentations. The diagnosis of PE depends highly on imaging studies, which may also provide prognostic information. This study aimed to describe the clinical and imaging profiles of patients with PE, emphasizing the differences between central and peripheral PE.

METHODS

After ethics review board approval, this retrospective observational study examined the non-negative results in adult patients who underwent computed tomography pulmonary angiography (CT-PA) at our hospital between May 2016 and December 2019. Demographic and clinical information and imaging findings were collected from the electronic medical records.

RESULTS

The study included 85 cases that were identified after re-interpreting the 103 non-negative CT-PA scans. Six cases were excluded for incomplete data and 12 cases were false-positive. Central PE was found in 63.5% of the cases. Obesity was the most common risk factor seen in 37.6% of the cases. Furthermore, 9.4% of the patients had sickle cell disease, which tended to be associated with peripheral PE. There was no difference between the peripheral and central PE in most clinical and imaging parameters evaluated (P > 0.05). However, patients with isolated subsegmental PE were more likely to develop hemoptysis (P = 0.04).

CONCLUSION

This study suggests that patients with obesity and sickle cell disease constitute an important proportion of all PE cases. Furthermore, the clinical and imaging profiles in patients with peripheral PE are similar to those in patients with central PE. Future research should focus on the clinical value of peripheral PE in patients with sickle cell disease.

Decreased size of the left anterior descending coronary artery is an independent predictor of deterioration in non-high-risk patients with acute pulmonary embolism

To evaluate the efficacy of measuring left coronary artery size to predict deterioration in non-high-risk acute pulmonary embolism (PE) patients. This retrospective study enrolled non-high-risk acute PE patients from January 2011 to December 2019. Patient deterioration was defined as the occurrence of adverse events within 30 days of hospital admission. Patients with adverse events were sex- and age-matched to patients without adverse events. Risk stratification was performed. Cross-sectional areas (CSAs) of the left main and left anterior descending (LAD) coronary artery inlets were measured. The main pulmonary artery (MPA) inlet and outlet and MPA LAD plane, which adjoined the LAD in the MPA, were reconstructed. CSAs, perimeters, and hydraulic diameters were measured to evaluate MPA size and deformation. Cardiac volume was also measured. Quantitative parameters were divided into tertiles. After adjustment by risk stratification, univariate and multivariate analyses were performed. Correlations between different parameters were analysed. Seventy-three patients with adverse events were matched to 73 patients without adverse events. The results of the univariate and multivariate analyses revealed that LAD inlet CSAs (middle and high) predicted adverse events (odds ratio: 0.28 and 0.07, 95% confidence interval: 0.10-0.77 and 0.02-0.22, p = 0.013 and < 0.0001). LAD inlet CSA was strongly and negatively correlated with MPA LAD hydraulic diameter and CSA (correlation coefficients: - 0.643 and - 0.604, p < 0.001). LAD inlet CSA measurement would facilitate adverse event prediction in non-high-risk acute PE patients on the basis of risk stratification. The dilated MPA may involve the decrease in LAD inlet CSA.

A Novel Predictive Method Incorporating Parameters of Main Pulmonary Artery Bifurcation for Short-Term Prognosis in Non-high-risk Acute Pulmonary Embolism Patients

The aim of this study was to build a formula to predict short-term prognosis using main pulmonary artery (MPA) parameters reconstructed from computed tomographic pulmonary angiography in non-high-risk acute pulmonary embolism (PE) patients. After reconstructing the MPA and its centerline, the MPA, the right and left pulmonary artery inlet, and the MPA outlet plane were differentiated to measure the cross-sectional area (CSA), the maximal diameter and the hydraulic diameter. The MPA bifurcation area, volume and angle were measured. MPA dilation was defined as >29 mm at the transverse section plane. The patients were randomly divided into a training set and a validation set. A least absolute shrinkage and selection operator (LASSO) logistic regression algorithm was used to build a predictive formula. The performances of the predictive formula from LASSO were tested by the area under the receiver operating characteristic curve (AUC) and precision-recall (PR) curve with 10-fold cross-validation. The clinical utility was assessed by decision curve analysis (DCA). In total, 296 patients were enrolled and randomly divided (50:50) into a training set and a validation set. The LASSO predictive formula (lambda.1SE) was as follows: 0.92 × MPA bifurcation area + 0.50 × MPA outlet hydraulic diameter + 0.10 × MPA outlet CSA. The AUCs of the predictive formula were 0.860 (95% CI: 0.795-0.912) and 0.943 (95% CI: 0.892-0.975) in the training set and validation set, respectively. The LASSO predictive formula had a higher average area under the PR curve than MPA dilation (0.71 vs. 0.23 in the training set and 0.55 vs. 0.23 in the validation set) and added a net benefit in clinical utility by DCA. Integration of MPA outlet CSA, hydraulic diameter, and bifurcation area with the LASSO predictive formula as a novel weighting method facilitated the prediction of poor short-term prognosis within 30 days after hospital admission in non-high-risk acute PE patients.

Prognostic characteristics and body mass index in patients with pulmonary embolism: does size matter?

Objective

The aim of this study was to explore the impact of body mass index (BMI) on prognostic indicators and clinical outcomes in patients with pulmonary embolism.

Methods

Patients with pulmonary embolism from the Hokusai venous thromboembolism (VTE) randomised clinical trial that compared two anticoagulant regimens were followed-up for 1 year (n=1911). Patients were analysed with regard to World Health Organization (WHO) BMI categories at baseline (underweight (<18.5), normal (18.5 to <25), overweight (25 to <30), obese I (30 to <35), obese II (35 to <40), and obese III (≥40)). Clinical and radiological prognostic characteristics for right ventricular dysfunction and adverse events were assessed with normal weight as a reference. Clinical outcomes were mortality, recurrent VTE, hospitalisation, bleeding and overall adverse events.

Results

The relationship between BMI categories and both prognostic parameters and clinical outcomes showed U-shaped curves. Adjusted odds ratios (aORs) were highest in patients who were grade III obese for both clinical parameters (N-terminal pro-brain natriuretic peptide (NT-proBNP) >600 and simplified pulmonary embolism severity index (sPESI)≥1; 2.9 and 1.6), and radiological parameters (pulmonary trunk>29 mm, right-to-left-ventricular ratio>1.0, and central emboli; aOR=4.3, 2.1 and 2.3). Bleeding was observed more frequently in the higher categories of obesity. In patients who were underweight, for NT-proBNP>600 and sPESI≥1 the aORs were 2.6 and 2.5, respectively; however, no major bleeding occurred in this category.

Conclusion

Several clinical and radiological prognostics characteristics and right ventricular dysfunction in pulmonary embolism are not evenly distributed among BMI categories. This is reflected in a trend towards worse outcomes in patients who are overweight and underweight.

Overweight patients with pulmonary embolism have a higher risk of heart dysfunction and worse outcomeshttp://bit.ly/2Pwtln0

The relationship between computed tomographic obstruction index and pulmonary vein cross-sectional area in acute pulmonary embolism

PURPOSE

To investigate whether the increased obstruction of the pulmonary arteries was associated with reduced pulmonary vein areas in acute pulmonary embolism (APE).

METHOD

We retrospectively analyzed a consecutive series of computed tomography pulmonary angiography studies of 107 patients with APE and 101 controls without APE between November 2010 and January 2019. The control and patient groups were compared with each other for differences between the mean cross-sectional areas of pulmonary veins. Further analysis was conducted by dividing the patient group into high-risk patients (≥ 20%) and low-risk patients (< 20%) according to the pulmonary arterial obstruction index. The mean cross-sectional area of the pulmonary veins in these two groups was compared.

RESULTS

The mean cross-sectional areas of the 4 pulmonary veins at the ostium level (CSAPV) were significantly lower for the patient group (mean: 102.6 mm²) compared with the control group (111.8 mm²) (p < 0.001). CSAPV cutoff value for determining the diagnosis of APE that maximized the accuracy was 109.12 mm² (AUC = 0.721; 95% CI 0.649-0.794); its sensitivity and specificity were 78.2% and 69.2%, respectively. CSAPV cutoff value for differentiating high-risk APE that maximized the accuracy was 102.6 mm² (AUC = 0.634; 95% CI 0.525-0.743); its sensitivity and specificity were 61.9% and 53.8%, respectively.

CONCLUSIONS

There is a negative correlation between the CSAPV and thrombotic material burden in the pulmonary arteries of patients with APE. Hence, the CSAPV can be used as a diagnostic tool in the evaluation of the presence and severity of pulmonary embolism.

Computed tomography pulmonary angiography for acute pulmonary embolism: prediction of adverse outcomes and 90-day mortality in a single test

Purpose

Pulmonary embolism (PE) is a potentially fatal cardiopulmonary disease; therefore, rapid risk stratification is necessary to make decisions of appropriate management strategies. The aim of this study was to assess various computed tomography (CT) findings in order to find new prognostic factors of adverse outcome and mortality.

Material and methods

The study enrolled 104 patients with acute PE. Based on their outcome, patients were categorised into four groups. Comorbidities such as ischaemic heart disease were obtained from their medical records. Patients CT angiography were reviewed for recording variables such as main pulmonary artery diameter and right ventricle (RV)/left ventricle (LV) ratio. Patient deaths up to three months since diagnosis of PE had been registered. Logistic regression analysis was performed to find predictors.

Results

Based on multiple logistic regression, RV/LV ratio, LV diameter, and right-sided pulmonary infarction are predictors of mortality in 30 days. An RV/LV ratio of 1.19 could successfully discriminate patients who died within 30 days and those who did not.

Conclusions

RV/LV ratio, LV diameter, right-sided pulmonary infarction, assessed with helical CT, can help predict 30-day mortality.

Determinants and prognostic implication of diagnostic delay in patients with a first episode of pulmonary embolism

Signs and symptoms of pulmonary embolism (PE) are not specific and this can lead to a diagnostic delay. Little is known about the determinants of this delay and its prognostic implication. We conducted a retrospective analysis of a prospective cohort involving 514 patients with a first episode of PE. The diagnostic delay was defined as a time from first symptom onset to diagnosis of >3 days, corresponding of the median time in the population. Multivariable logistic regression analysis was performed to identify determinants of diagnostic delay. Prognostic implication was measured as the occurrence of 30-day all-cause mortality, haemodynamic collapse or recurrent PE. A total of 240 (47%) among 514 patients had a time from first symptom to diagnosis > 3 days. Previous deep vein thrombosis (OR 0.55, 95% Confidence Interval (CI), 0.32-0.93), immobilization (OR 0.52, 95% CI, 0.28-0.96), surgery (OR 0.31, 95% CI, 0.16-0.62), chest pain (OR 0.58, 95% CI, 0.39-0.86), syncope (OR 0.48, 95% CI, 0.23-1.01), dyspnea (OR 2.48, 95% CI, 1.57-3.91) and hemoptysis (OR 3.57, 95% CI, 1.40-9.07) were associated with diagnostic delay. Twenty-two patients (4.3%, 95%CI, 2.8-6.5) experienced an outcome event within 30 days. Among them, 15 patients (6.2% 95%CI, 3.7-10.3) had a diagnostic delay and 7 (2.6%, 95% CI 1.1-5.4) did not (p = 0.039). In this cohort, diagnostic delay is associated with the absence of major risk factors for PE or clinical features such as chest pain or syncope and the presence of dyspnea or hemoptysis. Diagnostic delay is associated with a worse 30-day prognosis.