ClotCare: Blood Clots, Stroke, Heart Attack
Sunday, April 23, 2017
Home   |   DVT/PE   |   Blood Clots   |   Coumadin/Warfarin   |   New Patients   |   Self Testing   |   Email List   |   Donate

Pick a Topic:

Find info on a:

We subscribe to the HONcode principles of the HON Foundation. Click to verify.
ClotCare complies with the HONcode standard for trustworthy health
information:
verify here.

ClotCare is a member of the Coalition to Prevent Deep Vein Thrombosis (DVT Coalition)  ClotCare is a member organization of the Coalition to Prevent Deep Vein Thrombosis. Click here to learn more about the Coalition to Prevent Deep Vein Thrombosis and DVT Awareness Month, which is held each March.

Is it safe to omit additional tests if d-Dimer is negative?

Ruth Morrison RN, BSN, CVN
August, 2006

Study: Kearon C, Ginsberg JS, Douketis J, et. al. An evaluation of D-dimer in the diagnosis of pulmonary embolism: a randomized trial. Ann Intern Med. 2006 Jun 6;144(11):812-21.

D-Dimer is a fibrin-derived fragment that is released into the circulation when cross-linked fibrin is broken down by the fibrinolytic system. Elevated levels of d-dimer are common in patients with venous thromboembolism. In several previous cohort and management studies, patients with the combination of a negative d-dimer and a low clinical suspicion of pulmonary embolism were unlikely to suffer pulmonary embolism. Prior to this study, the safety of omitting additional diagnostic testing in selected patients with suspected pulmonary embolism and a negative d-dimer test results had not been studied.

The goal of the trial was to determine if it is safe to withhold additional testing in patients with suspected pulmonary embolism (PE) and negative d-dimer test results. The trial was to test the hypothesis that patients with negative D-dimer test results who do not undergo further testing for pulmonary embolism will not have a higher frequency of venous thromboembolism during follow-up than patients who receive usual diagnostic testing and management.

The trial studied 2 subgroups of patients with suspected pulmonary embolism and negative d-dimer test results: patients with a low clinical suspicion of pulmonary embolism (group A) and those with a moderate or high clinical probability of PE who had a nondiagnostic ventilation-perfusion lung scan and no proximal deep venous thrombosis on venous ultrasonography (group B). Prior to diagnostic testing, the Wells 7-item prediction rule was utilized to categorize the patient’s clinical probability of pulmonary embolism as either low or moderate to high.

The experimental intervention for both probability groups was no further diagnostic testing for PE. The control intervention for the low probability group was a ventilation-perfusion lung scan followed by ultrasonography of the proximal deep leg veins on the same day. If the lung scan was nondiagnostic, ultrasound of the leg veins was repeated 7 and 14 days later. The control intervention for the moderate or high-probability group was ultrasonography of the proximal deep veins of the legs after 7 and 14 days.

Study duration was 6 months. At 6 months, 0 of 182 (group A) and 1 of 41 (group B) patients with no further testing had had symptomatic venous thromboembolism, compared with 1 of 185 (group a) and 0 of 41 (group B) patients with further testing. The study demonstrated that it is safe to withhold additional diagnostic testing in outpatients and inpatients with a low clinical suspicion of pulmonary embolism and a negative d-dimer test results.

Ask a question about blood clots or anticoagulant medications Have questions? Ask ClotCare. Send questions by email to webmaster@clotcare.org.

ClotCare is a 501(c)(3) non-profit organization generously supported by your tax-deductible donations and grants from our industry supporters.

Blood Clot Activities Calendar

New Postings:

An Update on Testosterone Supplementation and Venous Thrombosis by Charles J. Glueck, M.D.

Seeking Patients Taking Warfarin (Coumadin) for a Brief Survey

Click here to view full list of new postings
ClotCare Home | New Postings | Patient Postings | Clinician Postings | Join Our Email List | Useful Web Links
CE Opportunities | Training Programs | DVT & PE Stories | Editorial Board | Financial Support
About ClotCare | DVT Coalition | Donate to ClotCare | Contact Us
Key topics discussed on ClotCare include: Blood Clots | Deep Vein Thrombosis (DVT) | Pulmonary Embolism (PE) | Atrial Fibrillation (A. Fib or AF) | Heart Attack | Stroke | Transient Ischemic Attack (TIA) | Mini Stroke | Bleeding Complications | Vascular Surgery | Surgical Blood Clot Removal | Warfarin | Coumadin | Lovenox | Low Molecular Weight Heparin (LMWH) | Heparin | Anticoagulants | Plavix | Aspirin | Antiplatelets | Blood Thinners
Copyright 2000-2014 by ClotCare. All rights reserved.
Terms, Conditions, & Privacy | Image Copyright Information
19260 Stone Oak Parkway, Suite 101 | San Antonio, TX 78258 | 210-495-4335
Send comments to webmaster@clotcare.org.
Sunday, April 23, 2017