Renal dysfunction improves risk stratification and may call for a change in the management of intermediate- and high-risk acute pulmonary embolism: results from a multicenter cohort study with external validation

Performance of the Simplified Pulmonary Embolism Severity Index in predicting 30-day mortality after acute pulmonary embolism: Validation from a large-scale cohort

BACKGROUND

The performance of existing prognostic scores including the simplified Pulmonary Embolism Severity Index (sPESI) for short-term mortality of non-high-risk PE in Chinese population has not been widely validated.

METHODS

Non-high-risk patients were included from the prospective cohort of the China pUlmonary Thromboembolism REgistry Study (CURES). The sPESI, RIETE, Geneva, modified FAST, and Bova score were validated. The discriminatory performance was measured by the area under the curve (AUC). We also compared the sensitivity, odds ratio, specificity, positive predictive value and negative predictive value of these scores.

RESULTS

A total of 6,873 non-high-risk patients with acute PE were included and 241 (3.5 %) patients died within 30 days. Compared to the Geneva, modified FAST, and Bova score, the AUCs for predicting 30-day death of sPESI and RIETE score were higher at 0.712 (95 % CI, 0.680, 0.743) and 0.723 (95 % CI, 0.691, 0.755) respectively. The sPESI demonstrated the highest sensitivity at 0.809, while the RIETE score, Geneva, Modified FAST and BOVA score showed sensitivities of 0.622, 0.568, 0.477 and 0.502 respectively. A sPESI ⩾1 point was associated with a 4.7-fold increased risk of 30-day all-cause mortality (95 % CI, 3.427, 6.563, p < 0.001), while a RIETE score of ⩾1 point was associated with a 4.5-fold increased risk (95 % CI, 3.127, 6.341, p < 0.001). The Geneva score, modified FAST and Bova score showed inferior performance.

CONCLUSIONS

The implementation of the fewer-parameter, easier-to-calculate sPESI in Chinese patients with PE can help to discriminate patients with extremely low risk of short-term mortality for home treatment or early discharge.

Enoxaparin for Long-Term Therapy of Venous Thromboembolism in Patients with Cancer and Renal Insufficiency

BACKGROUND

 The optimal therapy of venous thromboembolism (VTE) in cancer patients with renal insufficiency (RI) is unknown. Current guidelines recommend to use low-molecular-weight heparin over direct oral anticoagulants to treat VTE in cancer patients at high risk of bleeding.

METHODS

 We used the Registro Informatizado Enfermedad Tromboemb00F3lica (RIETE) registry to compare the 6-month incidence rates of (1) VTE recurrences versus major bleeding and (2) fatal pulmonary embolism (PE) versus fatal bleeding in three subgroups (those with mild, moderate, or severe RI) of cancer patients receiving enoxaparin monotherapy.

RESULTS

 From January 2009 through June 2022, 2,844 patients with RI received enoxaparin for ≥6 months: 1,432 (50%) had mild RI, 1,168 (41%) moderate RI, and 244 (8.6%) had severe RI. Overall, 68, 62, and 12%, respectively, received the recommended doses. Among patients with mild RI, the rates of VTE recurrences versus major bleeding (4.6 vs. 5.4%) and fatal PE versus fatal bleeding (1.3 vs. 1.2%) were similar. Among patients with moderate RI, VTE recurrences were half as common as major bleeding (3.1 vs. 6.3%), but fatal PE and fatal bleeding were close (1.8 vs. 1.2%). Among patients with severe RI, VTE recurrences were threefold less common than major bleeding (4.1 vs. 13%), but fatal PE was threefold more frequent than fatal bleeding (2.5 vs. 0.8%). During the first 10 days, fatal PE was fivefold more common than fatal bleeding (2.1 vs. 0.4%).

CONCLUSION

 Among cancer patients with severe RI, fatal PE was fivefold more common than fatal bleeding. The recommended doses of enoxaparin in these patients should be revisited.

Comparison of diuretics and fluid expansion in the initial treatment of patients with normotensive acute pulmonary embolism: a systematic review and meta-analysis

BACKGROUND

Right ventricular (RV) dysfunction is the main cause of death in patients with normotensive acute pulmonary embolism (PE). The optimal management for this subset of patients remains uncertain. This systematic review and meta-analysis focused on the comparison of diuretics and fluid expansion in patients with acute PE presenting with RV dysfunction and haemodynamic stability.

METHODS

A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines considering only RTCs. The authors searched the traditional and grey literature through 1 November 2022. Meta-analysis used open source packages in R. Inverse variance fixed-effects models with OR as the effect measure were used for primary analyses. The main outcomes defined in this review protocol included pulmonary arterial systolic pressure (PASP), creatinine value changes and N-terminal pro-B-type natriuretic peptide during the first 24 hours.

RESULTS

Four studies with a total of 452 patients met the inclusion criteria. The baseline characteristics of patients were similar across all studies. Overall, patients receiving diuretics had a significant 24 hours reduction in pro-B-type natriuretic peptide (standard mean difference of -41.97; 95% CI -65.79 to -18.15), and PASP (standard mean difference of -5.96; 95% CI -8.06 to -3.86). This group had significantly higher creatinine levels (standard mean difference of 7.74; 95% CI 5.04 to 10.45). The quality of the studies was heterogeneous; two had a low risk of bias, and the other two had a high risk of bias.

CONCLUSIONS

Very few studies have compared the efficacy and safety of diuretics and fluid expansion in normotensive patients with acute PE with RV failure. Overall, furosemide appears to reduce RV dysfunction in this subset of patients compared with fluid expansion. Further research is required to confirm these findings.

MACHINE LEARNING FOR PREDICTING HEMODYNAMIC DETERIORATION OF PATIENTS WITH INTERMEDIATE-RISK PULMONARY EMBOLISM IN INTENSIVE CARE UNIT

ABSTRACT

Background: Intermediate-risk pulmonary embolism (PE) patients in the intensive care unit (ICU) are at a higher risk of hemodynamic deterioration than those in the general ward. This study aimed to construct a machine learning (ML) model to accurately identify the tendency for hemodynamic deterioration in the ICU patients with intermediate-risk PE. Method: A total of 704 intermediate-risk PE patients from the MIMIC-IV database were retrospectively collected. The primary outcome was defined as hemodynamic deterioration occurring within 30 days after admission to ICU. Four ML algorithms were used to construct models on the basis of all variables from MIMIC IV database with missing values less than 20%. The extreme gradient boosting (XGBoost) model was further simplified for clinical application. The performance of the ML models was evaluated by using the receiver operating characteristic curve, calibration plots, and decision curve analysis. Predictive performance of simplified XGBoost was compared with the simplified Pulmonary Embolism Severity Index score. SHapley Additive explanation (SHAP) was performed on a simplified XGBoost model to calculate the contribution and impact of each feature on the predicted outcome and presents it visually. Results: Among the 704 intermediate-risk PE patients included in this study, 120 patients experienced hemodynamic deterioration within 30 days after admission to the ICU. Simplified XGBoost model demonstrated the best predictive performance with an area under the curve of 0.866 (95% confidence interval, 0.800-0.925), and after recalibrated by isotonic regression, the area under the curve improved to 0.885 (95% confidence interval, 0.822-0.935). Based on the simplified XGBoost model, a web app was developed to identify the tendency for hemodynamic deterioration in ICU patients with intermediate-risk PE. Conclusion: A simplified XGBoost model can accurately predict the occurrence of hemodynamic deterioration for intermediate-risk PE patients in the ICU, assisting clinical workers in providing more personalized management for PE patients in the ICU.

The Predictive Value of the MELD Scores for In-Hospital Adverse Events in Normotensive Patients with Acute Pulmonary Embolism

The model for end-stage liver disease (MELD) and the model for end-stage liver disease excluding international normalized ratio (INR) (MELD-XI) scores, which reflect dysfunction of liver and kidneys, have been reported to be related to the prognosis of patients with right-sided "backward" failure. However, the relationship between the MELD/MELD-XI score and the in-hospital adverse events in pulmonary embolism (PE) patients was unknown. Normotensive PE patients were retrospectively enrolled at China-Japan friendship hospital from January 2017 to February 2020. The primary outcome was defined as death and clinical deterioration during hospitalization. Multivariate logistic analysis was used to explore the association between the MELD and MELD-XI scores for in-hospital adverse events. We also compared the accuracy of the MELD, MELD-XI, and the pulmonary embolism severity index (PESI) score using the time-dependent receiver operating characteristic curve and corresponding areas under the curve (AUC). A total of 222 PE patients were analyzed. Logistic regression analysis showed that the MELD score was independently associated with in-hospital adverse events (odds ratio = 1.115, 95% confidential interval = 1.022-1.217, P = .014). The MELD score has an AUC of 0.731 and was better than PESI (AUC of 0.629) in predicting in-hospital adverse events. Among PE patients with normal blood pressure on admission, the MELD score was associated with increased in-hospital adverse events.

Additive prognostic value of serum calcium to the ESC risk stratification in patients with acute pulmonary embolism

BACKGROUND

Hypocalcemia has been shown to be involved in the adverse outcomes of acute pulmonary embolism (APE). We aimed to determine the incremental value of adding hypocalcemia, defined as serum calcium level ≤ 2.12 mmol/L, on top of the European Society of Cardiology (ESC) prognostic algorithm, for the prediction of in-hospital mortality in APE patients, which in turn could lead to the optimization of APE management.

METHODS

This study was conducted at West China Hospital of Sichuan University from January 2016 to December 2019. Patients with APE were retrospectively analyzed and divided into 2 groups based on serum calcium levels. Associations between hypocalcemia and adverse outcomes were assessed by Cox analysis. The accuracy of risk stratification for in-hospital mortality was assessed with the addition of serum calcium to the current ESC prognostic algorithm.

RESULTS

Among 803 patients diagnosed with APE, 338 (42.1%) patients had serum calcium levels ≤ 2.12 mmol/L. Hypocalcemia was significantly associated with higher in-hospital and 2-year all-cause mortality compared to the control group. The addition of serum calcium to ESC risk stratification enhanced net reclassification improvement. Low-risk group with serum calcium level > 2.12 mmol/L had a 0% mortality rate, improving the negative predictive value up to 100%, while high-risk group with serum calcium level ≤ 2.12 mmol/L indicated a higher mortality of 25%.

CONCLUSION

Our study identified serum calcium as a novel predictor of mortality in patients with APE. In the future, serum calcium may be added to the commonly used ESC prognostic algorithm for better risk stratification of patients suffering from APE.

Deep vein thrombosis symptoms and 30-day mortality in acute pulmonary embolism

BACKGROUND

In patients with acute symptomatic pulmonary embolism (PE), the presence of concomitant lower-limb deep vein thrombosis (DVT) has been associated with a higher mortality rate. The prognostic significance of DVT symptoms among these patients remains uncertain.

METHODS

We used the RIETE (Registro Informatizado de Enfermedad TromboEmbólica) registry to compare the 30-day mortality rate in patients with PE and concomitant lower-limb DVT, according to the presence or absence of DVT symptoms. Primary outcomes were all-cause death and PE-related death within the first 30 days.

RESULTS

Since March 2001 to June 2021, there were 17,742 patients with acute symptomatic PE and objectively proven concomitant lower-limb DVT. Of these, 11,984 (68%) had DVT symptoms. Most patients with or without DVT symptoms (82% vs. 81%) received low-molecular-weight heparin initially. Then, most (61% vs. 58%) switched to vitamin K antagonists. During the first 30 days of therapy, 497 patients with DVT symptoms (4.1%) and 164 (2.8%) with no DVT symptoms died (rate ratio [RR]: 1.48; 95%CI: 1.23-1.77). The rates of PE-related death were: 1.0% vs. 0.7%, respectively (RR: 1.50; 95%CI: 1.04-2.16). On multivariable analysis, patients with DVT symptoms were at increased risk for all-cause death (adjusted hazard ratio [aHR]: 1.49; 95%CI: 1.24-1.78), and PE-related death (aHR: 1.52; 95%CI: 1.05-2.20).

CONCLUSION

Among patients with acute symptomatic PE and concomitant lower-limb DVT, those with DVT symptoms had an increased all-cause and PE-related mortality within 30 days. Assessment of DVT symptoms would assist with risk stratification of these patients.

An Update on the Management of Acute High-Risk Pulmonary Embolism

Hemodynamic instability and right ventricular (RV) dysfunction are the key determinants of short-term prognosis in patients with acute pulmonary embolism (PE). High-risk PE encompasses a wide spectrum of clinical situations from sustained hypotension to cardiac arrest. Early recognition and treatment tailored to each individual are crucial. Systemic fibrinolysis is the first-line pulmonary reperfusion therapy to rapidly reverse RV overload and hemodynamic collapse, at the cost of a significant rate of bleeding. Catheter-directed pharmacological and mechanical techniques ensure swift recovery of echocardiographic parameters and may possess a better safety profile than systemic thrombolysis. Further clinical studies are mandatory to clarify which pulmonary reperfusion strategy may improve early clinical outcomes and fill existing gaps in the evidence.

Risk stratification to optimize the management of acute pulmonary embolism

INTRODUCTION

Pulmonary embolism (PE) is a life-threatening disease. Risk stratification in patients with acute PE can guide clinical decisions. Clinical assessment, including hemodynamics, respiratory parameters, patient history, and right ventricle evaluation, has a pivotal role in this scope.

AREAS COVERED

This review aims to describe: i) the role of individual tools for prognostic stratification, from simple clinical parameters to the models suggested by international guidelines; ii) the implications of risk stratification in terms of patient disposition and treatment. The bleeding risk assessment in acute PE was also reviewed. The literature search was performed in PubMed and Embase to address these issues.

EXPERT OPINION

Prognostic assessment is essential to proceed with life-saving treatments in hemodynamically unstable patients and consider home treatment or short hospital stay in patients at low risk for death. In hemodynamically stable patients, risk stratification allows the implementation of personalized treatment pathways to reduce the risk of death, early PE recurrence, and bleeding. With the aim of optimizing healthcare resources, risk stratification may suggest appropriate patient disposition.

Risk Stratification in Patients with Acute Pulmonary Embolism: Current Evidence and Perspectives

Risk stratification is one of the cornerstones of the management of acute pulmonary embolism (PE) and determines the choice of both diagnostic and therapeutic strategies. The first step is the identification of patent circulatory failure, as it is associated with a high risk of immediate mortality and requires a rapid diagnosis and prompt reperfusion. The second step is the estimation of 30-day mortality based on clinical parameters (e.g., original and simplified version of the pulmonary embolism severity index): low-risk patients without right ventricular dysfunction are safely managed with ambulatory anticoagulation. The remaining group of hemodynamically stable patients, labeled intermediate-risk PE, requires hospital admission, even if most of them will heal without complications. In recent decades, efforts have been made to identify a subgroup of patients at an increased risk of adverse outcomes (intermediate-high-risk PE), who might benefit from a more aggressive approach, including reperfusion therapies and admission to a monitored unit. The cur-rent approach, combining markers of right ventricular dysfunction and myocardial injury, has an insufficient positive predictive value to guide primary thrombolysis. Sensitive markers of circulatory failure, such as plasma lactate, have shown interesting prognostic accuracy and may play a central role in the future. Furthermore, the improved security of reduced-dose thrombolysis may enlarge the indication of this treatment to selected intermediate–high-risk PE.

Development and validation of a prognostic tool: Pulmonary embolism short-term clinical outcomes risk estimation (PE-SCORE)

OBJECTIVE

Develop and validate a prognostic model for clinical deterioration or death within days of pulmonary embolism (PE) diagnosis using point-of-care criteria.

METHODS

We used prospective registry data from six emergency departments. The primary composite outcome was death or deterioration (respiratory failure, cardiac arrest, new dysrhythmia, sustained hypotension, and rescue reperfusion intervention) within 5 days. Candidate predictors included laboratory and imaging right ventricle (RV) assessments. The prognostic model was developed from 935 PE patients. Univariable analysis of 138 candidate variables was followed by penalized and standard logistic regression on 26 retained variables, and then tested with a validation database (N = 801).

RESULTS

Logistic regression yielded a nine-variable model, then simplified to a nine-point tool (PE-SCORE): one point each for abnormal RV by echocardiography, abnormal RV by computed tomography, systolic blood pressure < 100 mmHg, dysrhythmia, suspected/confirmed systemic infection, syncope, medico-social admission reason, abnormal heart rate, and two points for creatinine greater than 2.0 mg/dL. In the development database, 22.4% had the primary outcome. Prognostic accuracy of logistic regression model versus PE-SCORE model: 0.83 (0.80, 0.86) vs. 0.78 (0.75, 0.82) using area under the curve (AUC) and 0.61 (0.57, 0.64) vs. 0.50 (0.39, 0.60) using precision-recall curve (AUCpr). In the validation database, 26.6% had the primary outcome. PE-SCORE had AUC 0.77 (0.73, 0.81) and AUCpr 0.63 (0.43, 0.81). As points increased, outcome proportions increased: a score of zero had 2% outcome, whereas scores of six and above had ≥ 69.6% outcomes. In the validation dataset, PE-SCORE zero had 8% outcome [no deaths], whereas all patients with PE-SCORE of six and above had the primary outcome.

CONCLUSIONS

PE-SCORE model identifies PE patients at low- and high-risk for deterioration and may help guide decisions about early outpatient management versus need for hospital-based monitoring.