Diagnostic management of pulmonary embolism using clinical assessment, plasma D-dimer assay, complete lower limb venous ultrasound and helical computed tomography of pulmonary arteries

Abstract

The objective of the study was to assess the clinical validity of a non-invasive diagnostic strategy for acute pulmonary embolism using clinical assessment combined with both ELISA D-dimer and complete lower limb ultrasound (US) examination of proximal and distal veins, before single-detector helical computed tomography (CT) of pulmonary arteries. We expected the strategy to have a high diagnostic exclusion power and to safely decrease the number of CT scans. This prospective, multicenter outcome study included 274 consecutive outpatients. All underwent a priori clinical probability, D-dimer and bilateral complete lower limb US assessments. Only patients with a high clinical probability and both tests negative, or positive D-dimer and negative US assessments, underwent CT. This was deemed necessary in 114 patients (42%). At baseline, venous thromboembolism (VTE) was detected in 110 patients (40%), either by US showing proximal (n=65) or distal (n=36) thrombosis, or by CT (n=9). Anticoagulant was withheld in the remaining patients with negative results in both D-dimer and US but a non-high clinical probability (n=59), or in both US and CT (n=90), or with negative US (n=6) and inadequate CT (n=9). All patients underwent a three-month clinical follow-up. VTE occurred in one patient with inadequate CT, yielding an incidence of 0.6% [95% confidence interval: 0.1-3.4]. No patient died from VTE or had major bleeding. Using clinical probability, ELISA D-dimer and complete US before helical CT is a safe strategy resulting in a substantial reduction in CT scans.

Venöz Tromboemboli Tanısı Konulan Hastaların Tanımlayıcı Bulguları

“…This was similar with results of studies about Ddimer sensitivity (6,20). It was reported that when D-Dimer was used with clinical possibility, USG and CT, it is reliable for excluding VTE diagnosis 1,22,23,24 . There are studies suggesting this test has high negative predictive value 25,26 .…”

Relationship between the extent of deep venous thrombosis and the extent of acute pulmonary embolism as assessed by CT angiography

“…Venous thromboembolic disease comprises pulmonary embolism (PE) and deep venous thrombosis (DVT) [1][2][3][4][5][6][7][8][9][10][11][12]. A patient may present with either of these conditions, or both, and may not always exhibit the signs of one condition.…”

“…This is particularly concerning with silent PE, where the risk of death increases with the presence of coexisting pulmonary disease, right heart failure to compensate for pulmonary hypertension, and embolic recurrences (which come from the lower limb veins in 90% of cases, and which further increase pulmonary arterial obstruction) [13]. In patients clinically suspected of having PE, two imaging approaches have been recommended: investigating firstly the lower limb veins [8,9,11] or the pulmonary arteries [3,5,10,14]. If DVT or PE is found with either investigation, the presence of the alternative condition is often simply assumed and no further investigation is conducted.…”