Clinically suspected pulmonary embolism: is it safe to withhold anticoagulation after a negative spiral CT?

Abstract

The goal of this study was 3-month clinical outcome in nonanticoagulated patients with clinically suspected acute pulmonary embolism (PE) following a negative spiral CT. During a 6-month period 305 patients underwent spiral CT, of whom only 8 also had a lung scintigraphy. In patients with a final CT report read as not positive for acute PE, all hospital records and answers to a patient questionnaire were analyzed for episodes of venous thrombembolism (VTE). Acute PE was diagnosed at spiral CT in 61 patients (20%). Twenty-six of the remaining 244 patients were excluded from further analysis because of (a) long-term anticoagulation due to symptomatic acute deep venous thrombosis (n = 5), clinically diagnosed acute PE (n = 2), chronic recurrent VTE (n = 4), and cardiac disorders (n = 5); and (b) a normal perfusion scintigram (n = 4) or a negative pulmonary arteriogram (n = 6). Three patients were lost to follow-up. Among the remaining 215 patients only 10 had undergone a negative lower extremity venous study. Sixteen patients (7%) died during the follow-up period, 6 of whom underwent autopsy. Venous thrombembolism was diagnosed in three of the 215 patients (1.4%, 95% confidence limits: 0.5-4.0%), one causing the patient's death. Two patients had advanced thoracic malignancies and the third severe chronic obstructive pulmonary disease (84 years old). A negative spiral CT may be able to exclude clinically significant acute PE with the same accuracy as a normal lung scintigraphy or a negative pulmonary arteriography.

Management of suspected pulmonary embolism (PE) by D‐dimer and multi‐slice computed tomography in outpatients: an outcome study

“…The practical relevance of these results is supported by the prevalence of PE in the study population, which is similar to that in other large studies [5,6,9,12]. Moreover, the overall exclusion rate in this study was acceptable (12%) and is lower than that reported in many large multi-center trials [5,6,11].…”

“…The role of spiral CT in the diagnosis of PE has been extensively evaluated in recent years [6,9,[11][12][13][14]. The main impediment for single slice spiral CT has been the limitation of this modality to detect small peripheral emboli [2,15].…”

Investigation of relationship between the D-dimer and ischemia-modified albumin levels with the radiological imaging-based pulmonary embolism severity score in acute pulmonary embolism

“…None of the existing laboratory tests can reliably exclude the diagnosis and clinicians must therefore rely on diagnostic imaging methods. Improvement of the computerized tomography (CT) technique with the introduction of spiral CT has made this a commonly used method in recent years (2).…”

Spiral Computed Tomography for Acute Pulmonary Embolism

“…37,46,50 A burden of small peripheral emboli is also thought to have prognostic relevance in individuals with cardiopulmonary disease 46 and for the de- velopment of chronic pulmonary hypertension in patients with thromboembolic disease. 46 Although the accuracy of conventional single-slice spiral CT for the detection of isolated peripheral emboli may be limited, encouraging data are accumulating on the high negative predictive value of a normal spiral CT study 29,[51][52][53][54][55][56][57][58][59][60] (Table 2). According to these retrospective 29,51-58 and prospective 59,60 studies, patient outcome is not adversely affected if anticoagulation is withheld on the basis of a negative spiral CT study.…”