title: Clinically suspected acute recurrent pulmonary embolism: a diagnostic challenge.
abstract: It is unknown whether strategies validated for diagnosing pulmonary embolism (PE) are valid in patients with a history of PE. It was the objective of this study to investigate whether a diagnostic algorithm consisting of sequential application of a clinical decision rule (CDR), a quantitative D-dimer test and computed tomography (CT) safely ruled out a clinical suspicion of acute recurrent PE. Data were obtained from a diagnostic outcome study of patients suspected of PE. Acute recurrent PE was ruled out by an unlikely probability of PE (CDR score </= 4 points) combined with a normal D-dimer test (</= 500 ng/ml) or by a normal CT in all other patients. The primary outcome was the incidence of acute recurrent venous thromboembolism during three months of follow-up in patients with normal tests and not treated with anticoagulants. Of 3,306 patients suspected of acute PE, 259 patients (7.8%) had a history of PE of whom 234 were not treated with anticoagulants. The probability of PE was unlikely in 82 of 234 patients (35%), and 42 had a normal D-dimer test (18%), excluding recurrent PE. None of these patients had a thrombotic event during follow-up (0%, 95%CI: 0-6.9). A CT was indicated in all other patients (192) and ruled out recurrent PE in 127 patients (54%). Only one patient with a negative CT had a fatal recurrent PE during follow-up (0.8%; 95%CI: 0.02-4.3). In conclusion, this prospective study demonstrates the safety of ruling out a clinical suspicion of acute recurrent PE by a simple diagnostic algorithm in patients with a history of PE.
authors.affiliation: Department of General Internal Medicine- Endocrinology, Leiden University Medical Centre, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands. M.Nijkeuter@lumc.nl
authors.forename: Mathilde
authors.initials: M
authors.lastname: Nijkeuter
authors.forename: Hanneke
authors.initials: H
authors.lastname: Kwakkel-van Erp
authors.forename: Maaike
authors.initials: M
authors.lastname: Söhne
authors.forename: Lidwine W
authors.initials: LW
authors.lastname: Tick
authors.forename: Marieke J H A
authors.initials: MJ
authors.lastname: Kruip
authors.forename: Eric F
authors.initials: EF
authors.lastname: Ullmann
authors.forename: Mark H H
authors.initials: MH
authors.lastname: Kramer
authors.forename: Harry R
authors.initials: HR
authors.lastname: Büller
authors.forename: Martin H
authors.initials: MH
authors.lastname: Prins
authors.forename: Frank W G
authors.initials: FW
authors.lastname: Leebeek
authors.forename: Menno V
authors.initials: MV
authors.lastname: Huisman
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D003661:Decision Support Techniques; D003663:Decision Trees; D003937:Diagnosis, Differential; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D011237:Predictive Value of Tests; D011336:Probability; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000097:blood / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology; D012008:Recurrence; D015203:Reproducibility of Results; D012307:Risk Factors; D036542:Tomography, Spiral Computed
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D