CTPA as the gold standard for the diagnosis of pulmonary embolism

The estimated annual incidence of pulmonary embolism (PE) is between 69 to 205 cases per 100,000 persons-years. New imaging studies have been developed during the past decade. Chest CTPA, especially multidetector CT, has proven to be superior or equal to PA angiography, even detecting smaller filling defects. We reviewed the differences in opinion to the diagnosis of PE between chest radiologists (CR) who interpret CTPA and interventional radiologists (IR) who perform PA angiography and what they consider the "gold standard" for the diagnosis of PE.

Two surveys were designed, one for chest radiologists and one for interventional radiologists. An e-mail survey was sent to the members of the Society of Thoracic Radiology and the Society of Interventional Radiologists.

IR with < 10 years since finishing training were less likely to consider CTPA the gold standard, OR 0.45 (0.2-0.9). CR with < 10 years since finishing training were more likely to consider CTPA the gold standard, OR 2.0 (1.1-3.9). Most IR performed < 5 PA angiographies in the last 2 years (69%). CR considered CTPA the gold standard for the diagnosis of PE, OR 3.3 (1.8-6.1). Binary logistic regression analysis for both groups demonstrated that the only variable associated with CTPA as gold standard for the diagnosis of PE was being a chest radiologist.

The majority of the radiologists surveyed indicated that CTPA is the new reference standard for the diagnosis of pulmonary embolism. We agree with this statement based on the evidence available at this time.