Multidetector computed tomographic pulmonary angiography in patients with a high clinical probability of pulmonary embolism

Abstract

computed tomographic pulmonary angiography in patients with a high clinical probability of pulmonary embolism. J Thromb Haemost 2016; 14: 114-20. EssentialsWhen high probability of pulmonary embolism (PE), sensitivity of computed tomography (CT) is unclear. We investigated the sensitivity of multidetector CT among 134 patients with a high probability of PE. A normal CT alone may not safely exclude PE in patients with a high clinical pretest probability. In patients with no clear alternative diagnosis after CTPA, further testing should be strongly considered. Summary. Background: Whether patients with a negative multidetector computed tomographic pulmonary angiography (CTPA) result and a high clinical pretest probability of pulmonary embolism (PE) should be further investigated is controversial. Methods: This was a prospective investigation of the sensitivity of multidetector CTPA among patients with a priori clinical assessment of a high probability of PE according to the Wells criteria. Among patients with a negative CTPA result, the diagnosis of PE required at least one of the following conditions: ventilation/perfusion lung scan showing a high probability of PE in a patient with no history of PE, abnormal findings on venous ultrasonography in a patient without previous deep vein thrombosis at that site, or the occurrence of venous thromboembolism (VTE) in a 3-month follow-up period after anticoagulation was withheld because of a negative multidetector CTPA result. Results: We identified 498 patients with a priori clinical assessment of a high probability of PE and a completed CTPA study. CTPA excluded PE in 134 patients; in these patients, the pooled incidence of VTE was 5.2% (seven of 134 patients; 95% confidence interval [CI] 1.5-9.0). Five patients had VTEs that were confirmed by an additional imaging test despite a negative CTPA result (five of 48 patients; 10.4%; 95% CI 1.8-19.1), and two patients had objectively confirmed VTEs that occurred during clinical follow-up of at least 3 months (two of 86 patients; 2.3%; 95% CI 0-5.5). None of the patients had a fatal PE during follow-up. Conclusions: A normal multidetector CTPA result alone may not safely exclude PE in patients with a high clinical pretest probability.

Outcomes following a negative computed tomography pulmonary angiography according to pulmonary embolism prevalence: a meta‐analysis of the management outcome studies

“…A total of 3143 publications were retrieved from our literature search. Both primary reviewers finally agreed to include 22 articles in the final analysis [2,7,[21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40] (quadratic weighted kappa 0.692 [95% CI, 0.543-0.840]). The reasons for exclusion are described in Fig.…”

Scoring Systems for Diagnosis of Acute Venous Thromboembolism

“…On the other side of the spectrum, some studies and clinical guidelines suggest that patients with a high pretest probability of PE should undergo additional testing even if their CTPA is negative. 17,18 This remains a matter of debate, but based on recent data, physicians should not hesitate to order a leg CUS whenever a patient with a high pretest probability of PE presents with signs or symptoms of DVT. 18 Another use of pretest probability is to guide therapeutic management while waiting for the results of diagnostic tests.…”

“…17,18 This remains a matter of debate, but based on recent data, physicians should not hesitate to order a leg CUS whenever a patient with a high pretest probability of PE presents with signs or symptoms of DVT. 18 Another use of pretest probability is to guide therapeutic management while waiting for the results of diagnostic tests. The American College of Chest Physicians guidelines on antithrombotic therapy suggest that patients should receive anticoagulant therapy while awaiting the results of diagnostic tests if they have a high pretest probability of VTE, if they have an intermediate probability and tests are expected to be delayed for more than 4 hours, and if there is a low pretest probability and tests will not be performed within 24 hours.…”

Safety of multidetector computed tomography pulmonary angiography to exclude pulmonary embolism in patients with a likely pretest clinical probability

“…Moores et al recently performed a prospective noninterventional study to assess the safety of CTPA (64row) to exclude PE in outpatients presenting to the emergency department of an academic center in Madrid with suspected PE and a high pretest clinical probability as assessed by the three-level Wells rule. Among 134 patients with a high clinical probability and a negative CTPA finding, seven were diagnosed with VTE either by another test at baseline (n = 5) or during a 3-month follow-up (n = 2), corresponding to an overall 'failure rate' of CTPA alone of 5.2% (95% CI 1.5-9.0%) [7]. The authors thus concluded that CTPA alone may not safely exclude PE in patients with a high clinical probability.…”