Investigating suspected acute pulmonary embolism — what are hospital clinicians thinking?

Role of D-dimer Assays in the Diagnostic Evaluation of Pulmonary Embolism

The diagnosis of pulmonary embolism (PE) remains challenging despite the evolution of well-validated clinical algorithms over the past few decades, largely because of nonspecific clinical features altering clinician suspicion. D-dimer is a simple noninvasive test that is an essential part of the diagnostic algorithm but is often deemed to be of little value in patients who are elderly or have other comorbidities. We describe a case of an elderly man who presented with clinical features and initial imaging consistent with pneumonia and a positive D-dimer test. Adherence to the suggested diagnostic algorithm and obtaining chest imaging, however, prevented what could have been a catastrophic missed diagnosis of PE. We review existing evidence on the importance of suspecting PE in the presence of alternative diagnosis and explore the literature on the association between the magnitude of D-dimer and the diagnosis of PE.

Frequency of nonthromboembolic imaging abnormalities in pregnant women referred for computed tomography pulmonary arteriography

PURPOSE

The study sought to determine the frequency of nonthromboembolic imaging abnormalities in pregnant women referred for computed tomography pulmonary arteriography (CTPA).

MATERIALS AND METHODS

CTPA studies on 100 consecutive pregnant women performed over a 5-year period were reviewed independently by 2 radiologists, with conflicts resolved by consensus. Age range was 18-43 years (mean 28 years). The presence or absence of pulmonary embolism and of nonthromboembolic imaging abnormalities was recorded. These were graded as A if the abnormalities were thought to provide potential alternative explanations for acute symptoms, B if findings were incidental that required clinical or radiologic follow-up, and C if the findings did not require further action.

RESULTS

Pulmonary embolism was seen in 5 women. In 2 of these additional findings of consolidation and infarction were seen. Ninety-five women did not have pulmonary embolism. Eleven women (12%) had grade A abnormalities; 6 cases of consolidation, 2 cases of lobar collapse, and 3 cases of heart failure with pleural effusions. One woman had a grade B abnormality due to the presence of pulmonary nodules. Ten women had incidental grade C abnormalities.

CONCLUSION

Pulmonary embolism occurs in 5% of pregnant women referred for CTPA. In pregnant women without embolism on CTPA, potential alternative causes for patient symptoms are seen on CT in 12% of cases.