CMAJ • January 21, 2003; 168 (2) © 2003 Canadian Medical Association or its licensors NO SINGLE NONINVASIVE TEST for pulmonary embolism is both sensitive and specific. Some tests are good for "ruling in" pulmonary embolism (e.g., helical CT) and some tests are good for "ruling out" pulmonary embolism (e.g., D-dimer); others are able to do both but are often nondiagnostic (e.g., ventilation–perfusion lung scanning). For optimal efficiency, choice of the initial diagnostic test should be guided by clinical assessment of the probability of pulmonary embolism and by patient characteristics that may influence test accuracy. This selective approach to testing enables pulmonary embolism to be diagnosed or excluded in a minimum number of steps. However, even with the appropriate use of combinations of noninvasive tests, it is often not possible to definitively diagnose or exclude pulmonary embolism at initial presentation. Most of these patients can be managed safely without treatment or pulmonary angiography by repeating ultrasound testing of the proximal veins after one and 2 weeks to detect evolving deep vein thrombosis. Helical CT and MRI are rapidly improving as diagnostic tests for pulmonary embolism and are expected to become central to its evaluation.

Pulmonary embolism is one of the most important disorders affecting the pulmonary vasculature. The term pulmonary embolism refers to the movement of a blood clot from a vein through the right side of the heart to the pulmonary circulation; it then lodges in one or more branches of the pulmonary artery. The consequences of this problem are variable, ranging from none to sudden death, depending on the size of the embolus and the medical condition of the patient.

Acad Emerg Med Volume 13, Number 3 365, published online before print January 3, 2006, doi: 10.1197/j.aem.2005.11.046 © 2006 Society for Academic Emergency Medicine. Conclusions: These case reports suggest a role for bedside lung ultrasound to rule out pulmonary embolism in outpatients with isolated pleuritic pain and low pre-test probability, potentially reducing the need for further testing. Future prospective trials are needed to prove this hypothesis.

(Circulation. 2002;106:1436.) © 2002 American Heart Association, Inc.

December 09, 2003

(JAMA. 2001; 285:836) Published in JAMA: February 14, 2001

A pulmonary embolism (PULL-mun-ary EM-bo-lizm) is a sudden blockage in a lung artery, usually due to a blood clot that traveled to the lung from the leg. A clot that forms in one part of the body and travels in the bloodstream to another part of the body is called an embolus. March 2006

Respiratory Research 2008, 9:49doi:10.1186/1465-9921-9-49. IMA is a good alternative to D-dimer in PE diagnosis in terms of both cost and efficiency. Used in combination with clinical probability scores, it has a similar positive effect on NPV and sensitivity to that of D-dimer. The PPV of IMA is better than D-dimer, but it is still unable to confirm a diagnosis of PE without additional investigation.

Article by Dr. Craig Feied detailing the diagnosis and treatment of thrombosis events.