title: Can multislice CT alone rule out reliably pulmonary embolism? A prospective study.
abstract: OBJECTIVE
  To evaluate the safety of withholding anticoagulation in patients with suspected acute pulmonary embolism after negative multislice computed tomography (MSCT) pulmonary angiography and lower-limb venography.
  
  
  METHODS
  A total of 383 consecutive patients with suspected acute pulmonary embolism were prospectively studied. Patients underwent MSCT pulmonary angiography and lower-limb venography, as well as pulmonary scintigraphy and lower-limb ultrasound examination. Patients with negative MSCT results for both pulmonary embolism and venous thrombosis were not administered anticoagulants and were followed up for 6 months to rule out thromboembolism.
  
  
  RESULTS
  At MSCT, 156 patients were positive for pulmonary embolism, venous thrombosis, or both; 224 were negative; and findings were inconclusive in three. False-negatives were five patients with high probability scintigram and two with venous thrombosis detected at US. A total of 184 patients with negative MSCT and without anticoagulation were followed up for 6 months. During this period of time just one recurrence of pulmonary embolism was detected. The negative predictive value of MSCT pulmonary angiography plus lower-limb venography was 95.8% (183/191).
  
  
  CONCLUSIONS
  MSCT is efficacious in diagnosing pulmonary embolism, with negative predictive values reported in the literature ranging from 94% to 100%. This enables omission of anticoagulation in patients with suspected pulmonary embolism after negative MSCT findings without the need for other diagnostic tests.
authors.affiliation: Department of Diagnostic Imaging, Hospital Universitario La Fe, Spain. pamies_jos@gva.es
authors.forename: Jose Pamies
authors.initials: JP
authors.lastname: Guilabert
authors.forename: Dolores Nauffal
authors.initials: DN
authors.lastname: Manzur
authors.forename: Maria J Torres
authors.initials: MJ
authors.lastname: Tarrasa
authors.forename: Maximiliano Lloret
authors.initials: ML
authors.lastname: Llorens
authors.forename: Petra
authors.initials: P
authors.lastname: Braun
authors.forename: Maria P Bello
authors.initials: MP
authors.lastname: Arques
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage*; D005188:False Negative Reactions; D005260:Female; D005268:Femoral Vein / Q000000981:diagnostic imaging; D005500:Follow-Up Studies; D006801:Humans; D007866:Leg / Q000098:blood supply; D008297:Male; D008875:Middle Aged; D010690:Phlebography; D011152:Popliteal Vein / Q000000981:diagnostic imaging; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging* / Q000188:drug therapy; D011877:Radionuclide Imaging; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed; D018615:Ultrasonography, Doppler, Color; D020246:Venous Thrombosis / Q000000981:diagnostic imaging / Q000188:drug therapy; D028761:Withholding Treatment
chemical_list: D000925:Anticoagulants