Analysis of the effectiveness of the D-Dimer test to exclude acute venous thromboembolism

Abstract number: P1468

Rached R. A., Cavalheiro-Filho C., De Piano L. P. A., Rached R. D. V. A., Strunz C. M. C., Cardos L. F., Chamone D. A. F.

Heart Institute, Brazil

Introduction  

The diagnostic approach of acute thrombotic episode presents several difficulties and limitations, mainly because, on average, less than 30% of the individuals, with suggestive signs and symptoms of thrombosis, have the diagnosis confirmed. The dosage of plasmatic D-Dimer has been pointed as an option to exclude the occurrence of acute venous thromboembolism.

Objective  

We evaluated the effectiveness and the safety of the D-Dimer test (VIDAS-BioMérieux) to exclude acute venous thromboembolism.

Patients and methods  

We studied 131 patient (age 13–95 years) that attended the emergency service with suggestive clinical picture of pulmonary emboli (PE) and/or deep venous thrombosis (DVT). Among the patients, 93 (71%) subjects didn't present acute venous thromboembolism, while, 38 (29%) presented. Relating to the clinical symptoms, 63 patients presented suspicion of PE, being 18 (29%) confirmed; 49 patients presented suspicion of DVT, being 14 (29%) confirmed and; 19 patients presented suspicion of PE and DVT, being 6 (32%) confirmed.

Results  

Among the 93 patients without acute thrombotic episode, 63 (68%) presented plasmatic levels of D-Dimer above 500 ng mL^-1 (positive), while, all the 38 (100%) patients, with confirmation of acute venous thromboembolism, presented plasmatic levels of D-Dimer above 500 ng mL^-1 (positive). The D-Dimer test, for diagnosis of acute venous thromboembolism, presented sensibility of 100%; specificity of 32%; positive predictive value of 38%; negative predictive value of 100% and accuracy of 52%.

Conclusion  

Thirty (23%) patients, that didn't present acute venous thromboembolism and with plasmatic levels of D-Dimer below 500 ng mL^-1 (negative), could have avoided all the diagnostic investigation and therapeutic approach if D-Dimer test had been used in the diagnostic routine. No patient with acute venous thromboembolism had plasmatic levels of D-Dimer below 500 ng mL^-1 (negative). In this study we found that D-Dimer test (VIDAS-BioMérieux) was effective and safe to exclude acute PE and DVT.