Thrombosis and Hemostasis
K23: Pre-Test Probability for Pulmonary Embolism
PI: D. Mark Courtney, M.D.
Pulmonary embolism (PE) is caused by blood clots in the arteries of the lung. The most common symptoms of PE, chest pain and shortness of breath are included as the chief complaints of an estimated 10 million people in US EDs annually. An estimated 2%-5% of all ED visits at our emergency department include evaluation for this potentially life-threatening disorder. Previous work by Dr. Courtney suggested that PE may be the #2 cause of sudden unexpected outpatient death, behind coronary artery disease. Testing for PE must be done in conjunction with estimation of the pretest probability of disease, which is the likelihood the physician believes to be present in a given patient before any tests have been done. There are no uniformly used or accepted means of estimating pretest probability. There has also been a recent proliferation of blood screening tests for PE, which if normal, in low probability patients, may alone be used to exclude the diagnosis of PE. The ease of ordering a blood test to screen for PE may result in significant changes in test utilization rates and overall disease diagnosis. This prospective observational study will quantify the effects of a new quantitative D-dimer blood test on these three parameters, as well as test the hypothesis that low risk patients (Wells and Charlotte criteria) with a negative D-dimer have a very low prevalence of PE (<1.0%) as determined by imaging test results, and 3 month follow-up.
Funding Source: NIH, NHBLI
Funding Amount: $633,439
Funding Duration: 07/01/04 - 06/30/09
