title: Contribution of indirect computed tomography venography to computed tomography angiography of the chest for the diagnosis of thromboembolic disease in two United States emergency departments.
abstract: Recent reports suggest that physicians in non-ambulatory settings can use indirect CT venography (CTV) of the lower extremities immediately following spiral CT angiography (CTA) of the chest to identify patients with a negative CTA who have thromboembolic disease identified on CTV. We sought to determine the frequency of isolated deep venous thrombosis (DVT) discovered on CTV in emergency department (ED) patients with complaints suggestive of pulmonary embolism (PE) yet having a negative CTA. This study was conducted in a suburban and urban ED where patients with symptoms suspicious for PE were primarily evaluated with CTA and CTV. A total of 800 patients were studied, including 360 from the suburban ED and 440 from the urban ED. 88 (11%) patients were diagnosed with thromboembolic disease by CTA, or CTV, or both. Seventy-three patients had a CTA of the chest that was positive for PE, 42 (5.2%) of whom had evidence of both PE on CTA and DVT on CTV. Fifteen patients (2%, 95% CI = 1-3%) had a negative CTA and were subsequently found to have isolated DVT on CTV, all of whom received anticoagulation therapy. These data suggest that indirect CT venography of immediately following CT angiography of the chest significantly increased the frequency of diagnosed thromboembolic disease requiring anticoagulation in ED patients with suspected PE.
authors.affiliation: Department of Emergency Medicine and Mayo Clinic Hospital, Scottsdale, Arizona, USA.
authors.forename: P B
authors.initials: PB
authors.lastname: Richman
authors.forename: J
authors.initials: J
authors.lastname: Wood
authors.forename: D M
authors.initials: DM
authors.lastname: Kasper
authors.forename: J M
authors.initials: JM
authors.lastname: Collins
authors.forename: R W
authors.initials: RW
authors.lastname: Petri
authors.forename: A G
authors.initials: AG
authors.lastname: Field
authors.forename: D N
authors.initials: DN
authors.lastname: Cowles
authors.forename: J A
authors.initials: JA
authors.lastname: Kline
mesh_terms: D000328:Adult; D000368:Aged; D000792:Angiography / Q000379:methods*; D004632:Emergency Medical Services / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010690:Phlebography / Q000379:methods*; D011237:Predictive Value of Tests; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging; D013902:Radiography, Thoracic / Q000379:methods* / Q000592:standards; D012189:Retrospective Studies; D013923:Thromboembolism / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000592:standards; D014481:United States