Ruling out Pulmonary Embolism in Patients with High Pretest Probability

A 60-Year-Old Woman with a 6-Week History of Shortness of Breath and Intermittent Chest Pain Due to Chronic Thromboembolic Pulmonary Disease Undetected by Computed Tomography Pulmonary Angiography (CTPA) and Diagnosed by Ventilation-Perfusion Imaging

BACKGROUND Chronic thromboembolic pulmonary disease (CTEPD) is the persistent occlusion of pulmonary arteries resulting from 1 or more thrombo-emboli. Its presentation is often non-specific, with exertional dyspnea and fatigue, yet if left undiagnosed risks of chronic thromboembolic pulmonary hypertension and right-sided cardiac failure can ensue. Computed tomography pulmonary angiography (CTPA) and ventilation/perfusion (V/Q) imaging are most commonly utilized for investigating CTEPD. This report is of a 60-year-old woman with a 6-week history of breathlessness and intermittent chest pain due to CTEPD, undetected by CTPA and diagnosed by V/Q imaging. CASE REPORT A 60-year-old woman presented with a 6-week history of breathlessness, intermittent chest pain, and reduced mobility. Her past medical history included chronic obstructive pulmonary disease, pulmonary sarcoidosis, and obesity. Screening tests for infective and ischemic cardiac etiologies were unremarkable. A calculated Wells score was 6, making CTEPD the main differential diagnosis, and she was commenced on therapeutic dose anticoagulation. A CTPA performed on day 2 of admission showed no evidence of acute thromboembolic pulmonary disease or CTEPD. Instead, V/Q scintigraphy on day 6 revealed a perfusion mismatch in the right lung apex, consistent with CTEPD. The patient improved clinically and was discharged on long-term apixaban. CONCLUSIONS A negative CTPA does not necessarily exclude CTEPD. The sensitivity of CTPA for CTEPD is lower than that of V/Q imaging, and can hence lead to false-negative results, as this case highlights. When there is a high clinical suspicion for CTEPD but a negative CTPA study, V/Q imaging should always be undertaken.

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

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The study provides a cut-off value of RV diameter and CT obstruction index by CTPA to predict acute PE patients' mortality.

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RV diameter of 53 mm or over and CT obstruction index >70 % is associated with increased 30-day mortality in APE patients.

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Increased RV diameter by CTPA is a better predictor of mortality than the clinical Pulmonary Embolism Severity Index (PESI).

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CTPA can be valuable as both the diagnostic and prognostic tool in APE patients.

Objective

The purpose of the present study was to assess the implications of different parameters of computed tomography pulmonary angiography (CTPA) to predict 30-day mortality in acute pulmonary embolism (APE) patients.

Material and Method

Patients who had clinical suspicion of APE and underwent CTPA were recruited in a retrospective cohort study. The findings of the CTPA included the parameters of right ventricular dysfunction (RVD), the severity of obstruction to the pulmonary artery by CT obstruction index, and the ratio of pulmonary trunk diameter and aorta. The endpoint of the study was established as the 30-day mortality associated with APE.

Results

A total of 238 patients with a confirmed APE diagnosis with CTPA were included in the study; 26 (10.9 %) of those patients died within 30 days. In patients with cancer and the Pulmonary Embolism Severity Index (PESI) class 5, the mortality rate was significantly higher. Compared with survivors, the mean CT obstruction index in the non-survivor group was significantly higher (p < 0.001). Higher mortality was associated with all RVD parameters identified by CTPA, such as the RV/LV ratio (p < 0.001), interventricular septum deviation grade 3 (p < 0.001), increased RV diameter (p < 0.001), and IVC contrast reflux (p < 0.001). The highest adjusted odds ratio was RV diameter at 1.094, followed by PESI and the CT obstruction index at 1.040.

Conclusion

CTPA-detected RVD parameters and CT obstruction index can predict a 30-day mortality rate in APE patients and be used for risk stratification. In APE patients, the RV diameter of 53 mm or greater and the CT obstruction index >70% is associated with increased 30-day mortality.

Prognostic Value of D-Dimer in Younger Patients with Pulmonary Embolism

In patients with pulmonary embolism (PE), the D-Dimer assay is commonly utilized as part of the diagnostic workup, but data on D-Dimer for early risk stratification and short-term mortality prediction are limited. The purpose of this study was to determine D-Dimer levels as a predictive biomarker of PE outcomes in younger (<50 years of age) compared to older patients. We conducted retrospective analysis for 930 patients diagnosed with PE between 2015 and 2019 as part of the Serbian University Multicenter Pulmonary Embolism Registry (SUPER).All patients had D-Dimer levels measured within 24 hours of hospital admission. The primary outcome was mortality at 30 days or during hospitalization. Patients were categorized into two groups based on age (≤ 50 and >50 years of age). Younger patients constituted 20.5% of the study cohort. Regarding all-cause mortality, 5.2% (10/191)of patients died in group under the 50 years of age; the short-term all-causemortality was 12.4% (92/739) in older group.We have found that there was significant difference in plasma D-Dimer level between patients ≤ 50 years of age and older group (>50), p= 0.006.D-Dimer plasma level had good predictive value for the primary outcome in younger patients (c-statistics 0.710; 95% CI, 0.640-0.773; p<0.031). The optimal cutoff level for D-Dimer to predict PE-cause death in patients aged > 50 years was found to be 8.8 mg/l FEU(c-statistics 0,580; 95% CI 0.544-0.616; p=0.049). In younger PE patients, D-Dimer levels have good prognostic performance for 30-day all-cause mortalityand concentrations above 6.3 mg/l FEU are associated with increased risk of death. D-Dimer in patients aged over 50 years does not have predictive ability for all-caused short-term mortality. The relationship between D-Dimer and age in patients with PE may need further evaluation.