[Utility of probability scores for the diagnosis of pulmonary embolism in patients with SARS-CoV-2 infection: A systematic review]

Pulmonary Embolism Rule-out Criteria: Diagnostic Accuracy and Impact of COVID-19

BACKGROUND

The Pulmonary Embolism Rule-Out Criteria (PERC), developed to minimize unnecessary testing in low-risk pulmonary embolism (PE) cases, lacks clear validation in the context of COVID-19.

OBJECTIVES

To assess the validity of the PERC in emergency department patients having undergone computed tomography pulmonary angiography (CTPA) during the COVID-19 pandemic.

METHODS

We conducted a retrospective analysis of emergency department patients who underwent CTPA for suspected PE. COVID-19 status was based on the results of a reverse transcription-polymerase chain reaction (RT-PCR) test performed in the emergency department, or within 30 days prior to visiting the emergency department. We collected data on demographics, symptoms, d-dimer levels, and medical history relevant to thrombosis and conducted the PERC test using the criteria including age, oxygen saturation, heart rate, and the absence of hemoptysis or recent trauma. We categorized outcomes based on the concordance between the PERC results and CTPA findings, with specific definitions for true positive and negative, as well as false positive and negative results. We also evaluated the impact of COVID-19 status on the diagnostic performance of the PERC by analyzing the prevalence of PE in patients testing positive and negative for COVID-19.

RESULTS

Among the 2.430 participants, 45.1% tested negative for COVID-19, 43.4% tested positive, and 11.5% were untested. The PERC identified 91.2% of the cases as positive, 6.9% of which were confirmed to have PE. Overall, 84.9% of cases (n = 2.062) showed a discordant result between the PERC and CTPA findings. The lack of significant correspondence between the PERC positivity and actual PE presence (p = 0.001; p < 0.01) indicated low diagnostic concordance. In patients with a positive COVID-19 test result, the PERC demonstrated a sensitivity of 95.3% (95% CI: 86.91-99.02), a specificity of 9.1% (95% CI: 7.46-11.15), a positive predictive value of 6.3% (95% CI: 6.01-6.70), a negative predictive value of 96.8% (95% CI: 90.81-98.94), and an accuracy of 14.4% (95% CI: 12.34-16.67). In patients who tested negative for COVID-19, the sensitivity was 95.4% (95% CI: 88.64-98.73), the specificity was 7.8% (95% CI: 6.25-9.66), the positive predictive value was 8.1% (95% CI: 7.83-8.57), the negative predictive value was 95.1% (95% CI: 88.11-98.14), and the accuracy was 14.7% (95% CI: 12.73-17.02).

CONCLUSION

The study demonstrates that the sensitivity and negative predictive value of the PERC are comparable in COVID-19 positive and negative patients. Furthermore, the incidence of PE among patients presenting to the emergency department did not significantly differ based on COVID-19 status. While this study highlights the relevance of the PERC in clinical decision-making, caution is advised as the PERC may not always provide reliable results when used as the sole diagnostic test.

CT pulmonary angiography in the inpatients: A 5-year retrospective view at the end of COVID-19 public health emergency

To retrospectively evaluate the trends in utilization and results of computed tomography pulmonary angiography (CTPA study) for detection of acute pulmonary embolism (PE) in the hospital inpatients during different phases of COVID-19 public health emergency. We conducted an Institutional Review Board (IRB)-approved retrospective review of CTPA studies for our hospital inpatients in the years from 2019 to 2023, ranging from the prepandemic year (2019) to the year coinciding with the end of public health declarations (2023). Collected characteristics included patient age, patient sex, and result of the study. The utilization of CTPA studies for inpatients was higher in 2020 to 2023, compared to 2019 (3.8% in 2023 compared to 2.4% in 2019, P < .001). The increase in utilization was also statistically significant in each group, when stratified by age and sex (OR = 1.46 for female, OR = 1.71 for male, OR = 1.93 for elderly, and OR = 1.29 for non-elderly inpatients in 2023, compared to 2019). The positivity rate of acute PE in the inpatients was overall higher in 2021, 2022, and 2023, compared to 2019 (for example, 18.5% in 2023 compared to 14.3% in 2019, P = .01). When stratified by age and sex, only the non-elderly patients continued to have a significantly higher rate of acute PE in 2023, compared to 2019 (OR = 1.39). While studies spanning longer time frames and involving multiple institutions are needed to understand and generalize this conclusion, we conclude that the utilization and positivity rates of CTPA studies in inpatients remains high at the end of the COVID-19 pandemic public health emergency.

[Diagnostics and treatment of pulmonary artery embolisms]

In recent years the diagnostics of pulmonary artery embolisms (PE) has gained significance, with confirmation occurring in only about 15-25 % of suspected cases. Despite technological advances, radiological methods remain problematic due to radiation and contrast medium exposure. Clinical scores play a crucial role in the risk assessment of PE. High-risk situations call for specific measures, while negative D‑dimers can help avoid overdiagnosis. Computed tomographic pulmonary angiography (CTPA) remains the gold standard with high sensitivity and specificity. Treatment requires an interdisciplinary team (pulmonary embolism response team, PERT). Anticoagulation is an option for stable patients, while in unstable or unsuccessful courses, thrombolysis or interventional procedures can be considered. Side effects, especially the risk of bleeding, need to be considered for both forms of treatment.

CT pulmonary angiography in the emergency department: utilization and positivity rates during various phases of the COVID-19 pandemic

PURPOSE

To evaluate the trends in utilization and results of computed tomography pulmonary angiography (CTPA study) for detection of acute pulmonary embolism (PE) in the Emergency Department (ED) during different phases of COVID-19 public health emergency.

METHODS

We conducted a retrospective review of CTPA studies ordered through our ED in the months of March through May during five consecutive years from 2019 to 2023, designated as pre-pandemic, early, ongoing, recovery, and post-pandemic periods respectively. Collected characteristics included patient age, patient sex, and result of the study.

RESULTS

The utilization of CTPA studies for ED patients increased during the early, ongoing, and recovery periods. CTPA study utilization in the post-pandemic period was not significantly different from the pre-pandemic period (p = 0.08). No significant difference in CTPA study utilization was noted in the other periods when stratified by age group or sex, compared to the pre-pandemic period. The positivity rate of acute PE in ED patients was not significantly different in other periods compared to the pre-pandemic period.

CONCLUSION

At our institution, the utilization and positivity rates of CTPA studies for the ED patients were not significantly different in the post-pandemic period compared to the pre-pandemic period. While studies spanning a larger timeframe and involving multiple institutions are needed to test the applicability of this observation to a wider patient population beyond our defined post-pandemic period, we conclude that our study provides some confidence to the ordering provider and the radiologist in embracing the end of COVID-19 public health emergency by the WHO and the United States HHS with respect to CTPA studies.

Machine Learning-Based Prediction of Pulmonary Embolism Prognosis Using Nutritional and Inflammatory Indices

PURPOSE

This study aimed to create and assess machine learning (ML) models that utilize nutritional and inflammatory indices, focusing on the advanced lung cancer inflammation index (ALI) and neutrophil-to-albumin ratio (NAR), to improve the prediction accuracy of PE prognosis.

PATIENTS AND METHODS

We conducted a retrospective analysis of 312 patients, comprising 254 survivors and 58 non-survivors. The Boruta algorithm was used to identify significant variables, and four ML models (XGBoost, Random Forest, Logistic Regression, and SVM) were employed to analyze the clinical data and assess the performance of the models.

RESULTS

The XGBoost model, with optimal hyperparameters, achieved the best performance, with an accuracy of 0.882, an F1-score of 0.889, a precision of 0.917, a sensitivity of 0.863, a specificity of 0.905, and an AUC of 0.873. Analysis of feature importance indicated that the most critical predictors across models were respiratory failure, log-transformed ALI, albumin level, age, diastolic blood pressure, and NAR.

CONCLUSION

The ML-based prediction models effectively predicted the prognosis of PE, with the XGBoost model exhibiting good performance. Respiratory failure, ALI, albumin level, age, diastolic blood pressure, and NAR were correlated with PE prognosis.

Predictive value of hematological indices on incidence and severity of pulmonary embolism in COVID-19 patients

BACKGROUND

Pulmonary thromboembolism (PTE) is a common complication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which raises the COVID-19 disease's fatality rate from 3% to 45%. Nevertheless, due to fairly indistinguishable clinical symptoms and a lack of validated clinical prediction models, PTE diagnosis in COVID-19 patients is challenging. This study aims to investigate the applicability of hematological indices to predict PTE incidence and its severity in SARS-CoV-2 patients.

METHODS

A retrospective cohort study was conducted on hospitalized patients with a confirmed diagnosis of SARS-CoV-2 infection who underwent CT angiography to assess probable PTE in them. The correlation between complete blood count parameters 1 day before CT angiography and CT angiography outcomes, and simplified pulmonary embolism severity index (s-PESI) was investigated.

RESULTS

We discovered that among individuals with a probable PTE, males and those with higher platelet-to-lymphocyte (PLR) and neutrophil-to-lymphocyte (NLR) ratios had a greater likelihood of PTE incidence (p < .001, .027, and .037, respectively). PLR was a significant and independent predictor of PTE with a p value of .045. Moreover, a higher neutrophil count was associated with a higher s-PESI score in COVID-19 patients developing PTE (p: .038).

CONCLUSIONS

Among hematological indices, NLR and more precisely PLR are cost-effective and simply calculable markers that can assist physicians in determining whether or not COVID-19 patients with clinically probable PTE require CT angiography and the higher neutrophil count can be employed as an indicator of PTE severity in COVID-19 patients. Further large multicenter and prospective studies are warranted to corroborate these observations.