Simplification of the Diagnostic Management of Suspected Deep Vein Thrombosis

Open Access
Publisher Website
Google Scholar
Abstract
DURING THE past 2 decades, the diagnostic management of clinically suspected deep vein thrombosis of the lower extremity has considerably improved.1 Invasive diagnostic procedures such as contrast venography have gradually been replaced by noninvasive methods, most notably impedance plethysmography and compression ultrasonography. Results of both methods have shown a high accuracy for the diagnosis of symptomatic proximal vein thrombosis, but the sensitivity for nonocclusive or calf vein thrombi is much lower.2 Because these smaller thrombi may extend and give rise to pulmonary embolism, the concept of serial testing with repeated investigation during a 7- to 14-day period was introduced to rule out the disease.3-6 In 2 prospective studies, compression ultrasonography was shown to be superior to impedance plethysmography in detecting proximal venous thrombosis and in managing clinically suspected disease.6,7 Compression ultrasonography with an extended evaluation of the distal popliteal vein has recently been shown to safely reduce the number of investigations to 2 tests with an interval of 1 week.8,9 Although repeated testing remains mandatory to detect extending thrombi, the major disadvantage of this approach is that all patients with an initial normal ultrasonographic result need to undergo reinvestigation. Therefore, it has become desirable to develop new strategies that obviate the need for repeated testing in those patients at very low risk for thrombosis. For this purpose, D-dimer assays and clinical pretest probability scores have been advocated.10-12 At present, only a limited number of prospective studies have evaluated the usefulness of these novel methods in the actual treatment of symptomatic patients,13-16 and it is unknown which approach is most useful and suitable for daily medical practice.1