Pulmonary embolism in inpatients and outpatients: prevalence of disease vs other clinically significant findings in chest MDCT.

Pulmonary Embolism (PE) is the third most common acute cardiovascular disease and a frequent cause for acute hospital admission, with a reported associated mortality rate exceeding 15% in the first 3 months after the diagnosis [1,2]. In clinical practice, the diagnosis of acute PE continues to pose a challenge, because presenting symptoms and signs are non-specific, widely varying from one patient to another [3] Among diagnostic imaging modalities, Multi-Detector Computed Tomography (MDCT) is now considered the technique of choice for the depiction of the pulmonary vasculature when acute PE is suspected, replacing pulmonary angiography as the reference standard in this clinical scenario [4]. Due to its inherent capability to provide detailed visualization of chest anatomic structures, MDCT can also give additional diagnostic information on pulmonary parenchyma, mediastinum and thoracic wall, therefore leading to identify alternative causes for the patient’s clinical presentation [5; 6; 7]. Given the aforementioned diagnostic potentialities of chest MDCT and its high frequency of execution in the clinical practice when acute PE is suspected, the purpose of this study was to evaluate, over a long period of time, the clinical impact of chest MDCT in a large cohort of consecutive patients clinically suspected of having acute PE and referred to our Radiology Institute. Calculating the diagnostic yield of chest MDCT and the proportion of clinically relevant findings other than PE, in particular comparing the proportion of chest MDCT findings between hospitalized patients (in-patients) and patients referred from the Emergency Department (ED), afforded this.