Pulmonary Embolism Research

 Study of Pulmonary Embolism Emergency Department Diagnosis

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.

 In 2004, Dr. Courtney was awarded a K23 career development grant from the National Heart Lung and Blood Institute of the NIH.  This 5-year grant budget is $633,429 and is resulting in formal coursework, primary research, and future grant writing. This supports his work with the above Study of PE Emergency Department Diagnosis work.

 In 2005, Dr. Courtney was designated a site-PI for an NIH SSTR grant for development of novel technological solutions to allow maximally accurate and useful means of pretest probability assessment for PE.  This involves centers across the US and will ultimately be the world’s largest prospective PE study to date.

National Collaboration and Selected Publications:

Dr. Courtney continues to be a founding member of the Pulmonary Embolism Research Consortium (PERC), a national group of PE emergency medicine investigators.  They have collaborated on a manuscript that identified characteristics of patients that, when absent, indicate a sufficiently low likelihood of PE such that no testing may be indicated. (J. Thromb Haemost. 2004 Aug;2(8):1247-55.).

 Dr. Courtney serves as a national peer reviewer for Archives of Internal Medicine, Critical Care Medicine and Academic Emergency Medicine.  He has been on the national research committee of the Society of Academic Emergency Medicine (SAEM) for the past 5 years.