Safety of ruling out acute pulmonary embolism by negative CT pulmonary angiography in patients with a strict indication for CT: systematic review and meta-analysis
Abstract number: PP-WE-512
Mos1 I.C.M., Klok1 F.A., Kroft2 L.J.M., Roos de2 A., Dekkers3 O.M., Huisman1 M.V.
11Section of Vascular Medicine, Department of General Internal Medicine-Endocrinology 22Department of Radiology 33Department of Clinical Epidemiology and Department of Endocrinology and Metabolic Diseases, Leiden University Medical Center, Leiden, The Netherlands
How-to-cite Mos ICM, Klok FA, Kroft LJM, Roos de A, Dekkers OM, Huisman MV. Safety of ruling out acute pulmonary embolism by negative CT pulmonary angiography in patients with a strict indication for CT: systematic review and meta-analysis. Journal of Thrombosis and Haemostasis 2009; Volume 7, Supplement 2: Abstract PP-WE-512
Introduction: Several outcome studies have ruled out acute pulmonary embolism (PE) by negative computed tomography pulmonary angiography (CTPA). We performed a meta-analysis in order to determine the safety of this strategy in a specific group of patients with a strict indication for CTPA, i.e. with either ‘likely’ or ‘high’ clinical probability for PE, an elevated D-dimer concentration, or both.
Methods: Studies that ruled out acute PE by negative CTPA, with or without subsequent normal bilateral compression ultrasonography (CUS), in patients with a strict indication for CTPA, were searched for in Medline, EMBASE, Web of Science and the Cochrane dataset. Primary endpoint was the occurrence of (fatal) thromboembolic events (VTE) in a 3 month follow-up period.
Results: Three studies were identified that excluded PE by CTPA alone (2020 patients) and three studies that performed additional CUS of the legs after negative CTPA for PE (1069 patients). The pooled incidence of VTE was 1.2% (95% CI 0.8–1.8) based on a negative CTPA as a sole test and 1.1% (95% CI 0.6–2.0) based on negative CTPA and negative CUS, resulting in a NPV of 98.8% (95% CI 98.2–99.2) and 98.9% (95% CI 98.0–99.4) respectively. This compares favorably with the VTE failure rate after normal pulmonary angiography (1.7%, 95% CI 1.0–2.7). Pooled proportions of fatal PE did not differ between both diagnostic strategies (0.6% vs. 0.5%).
Conclusion: A negative CTPA alone can safely exclude PE in all patients in whom CTPA is required to rule out this disease. There is no need for additional ultrasonography to rule out VTE in these patients.
Disclosure of interest: Funded by NHS 2006-B224.
To cite this abstract use the following format:
Journal of Thrombosis and Haemostasis 2007; Volume 5, Supplement 2: abstract number
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