PE CT studies have risen nearly 50% in recent years
New data suggest that utilization of CT pulmonary angiography (CTPA) exams in emergency settings has significantly risen in recent years.
CTPA scans are considered the gold standard for ruling out pulmonary embolism due to their quick turnaround and accessibility. The scans also have high sensitivity and specificity and are much less invasive than catheter angiography.
As such, their utilization has seen substantial growth. New data published in Clinical Radiology indicate that CTPA use in EDs has grown by as much as 49% over the last 7 years. The diagnostic yield of the exam, however, has remained largely unchanged, prompting experts to question whether CTPAs are being overused in emergency settings.
“Overuse in this context refers to the high proportion of exams yielding negative results, particularly in patients with a low pretest probability of PE,” Marc D. Succi, MD, with the Innovation in Operations Research Center (MESH IO) at Mass General Brigham, and colleagues explained. “This overuse is driven in part by the need of ED providers to rule out not only PE but also other serious thoracic conditions, such as aortic dissection and malignancy, given their overlapping symptomatology.”
For the study, the team collected data from all CTPA exams completed at a quaternary urban ED from 2017 to 2023. CTPA volumes were compared to total ED visits and the total number of CTs conducted in the ED, while patient characteristics were stratified to determine whether any were associated with positivity rates.
During the time period studied, CTPA volume rose by 49%, increasing from 2,467 in 2017 to 3,684 in 2023. Positivity rates, however, remained stable at an average of 9.1%.
According to the team’s data, men—especially Black men—were more likely to have positive scans, while Asian patients had the lowest positivity rates. Higher BMI and a history of cancer also were predictive. Scans ordered during overnight shifts were less likely to be positive, but the group did not observe differences in diagnostic yield based on the ordering provider’s credentials (MD, DO, NP, PA).
The group suggested that the trend observed may be owed, at least in part, to the onset of COVID-19, as the virus resulted in significantly more patients with respiratory concerns presenting to EDs.
“These findings suggest a shift in imaging practice during and after the pandemic, but our study was not powered to confirm significance at the population level,” the authors explained. “The mean positivity rate of 9.1% aligns with prior studies reporting CTPA yields ranging from 6% to 34% and may be attributed to several factors, including the overuse of CTPA in low–risk patients, heightened concern for PE in patients with COVID–19, variability in adherence to clinical decision–making guidelines, and defensive medical practices.”
Learn more about the team’s observations here.
In addition to her background in journalism, Hannah also has patient-facing experience in clinical settings, having spent more than 12 years working as a registered rad tech. She began covering the medical imaging industry for Innovate Healthcare in 2021.