(HealthDay News) – For patients with suspected deep venous thrombosis (DVT), selective D-dimer testing is a safe and a more efficient testing strategy than universal testing, according to a study published in the Jan. 15 issue of the Annals of Internal Medicine.
Lori-Ann Linkins, MD, from McMaster University in Hamilton, Canada, and colleagues randomized consecutive symptomatic patients with a first episode of suspected DVT to receive either selective testing (860 patients) or uniform testing (863 patients). Selective testing was defined as D-dimer testing in outpatients with low or moderate clinical pretest probability (C-PTP) (DVT excluded at D-dimer levels <1.0µg/mL [low C-PTP] or <0.5µg/mL [moderate C-PTP]) and venous ultrasonography without D-dimer testing in inpatients and outpatients with high C-PTP, while uniform testing was defined as D-dimer testing for all participants (with DVT excluded at D-dimer levels <0.5µg/mL).
The researchers found that in both groups the incidence of symptomatic venous thromboembolism among patients not diagnosed with DVT during initial testing was 0.5% at three months. There was a 21.8% reduction in the proportion of patients who required D-dimer testing with the use of selective testing. With use of selective testing, the proportion of patients who required ultrasonography was reduced by 7.6% overall and by 21% for outpatients with low C-PTP.
“A selective D-dimer testing strategy seems as safe as and more efficient than having everyone undergo D-dimer testing when diagnosing a first episode of suspected DVT,” the authors write.
Several authors disclosed financial ties to the pharmaceutical industry.