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Clinical validity of negative helical computed tomography for clinical suspicion of pulmonary embolism

Alfonsa Friera1, María José Olivera, Carmen Suárez

  • 1Department of Radiology, Hospital de La Princesa, Universidad Autónoma, Madrid, Spain. alfita@mi.madritel.es

Respiration; International Review of Thoracic Diseases
|February 12, 2004
PubMed

Insights

Helical computed tomography (CT) effectively rules out pulmonary embolism. Patients with suspected pulmonary embolism and negative CT scans can safely avoid anticoagulant treatment, with no thromboembolic events detected in follow-up.

Area of Science:

  • Medical Imaging
  • Cardiology
  • Pulmonology

Background:

  • Helical computed tomography (CT) is a diagnostic tool for pulmonary embolism.
  • Assessing the safety of withholding anticoagulation in patients with suspected pulmonary embolism and negative CT findings is crucial.

Purpose of the Study:

  • To evaluate the clinical safety of not initiating anticoagulant treatment in patients with suspected pulmonary embolism who have a negative helical CT scan.

Main Methods:

  • A prospective study involved 209 patients with suspected pulmonary embolism undergoing helical CT.
  • Patients with negative CT results (n=132) did not receive anticoagulation and were followed for 3 months.
  • 99 patients completed the follow-up after exclusions.

Main Results:

  • No venous thromboembolic events were observed in the 90 patients without anticoagulation.
  • The negative predictive value of helical CT for pulmonary embolism was 99.09%.
  • Deaths occurred in 9% of patients, but were unrelated to thromboembolic disease.

Conclusions:

  • Helical CT is a safe and effective method for ruling out pulmonary embolism in patients with suspected cases.
  • Withholding anticoagulation in patients with negative helical CT findings is clinically safe.
  • Helical CT serves as a valuable front-line diagnostic tool for pulmonary embolism.
Abstract

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