Diagnosis of DVT: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines.
BACKGROUND
Objective testing for DVT is crucial because clinical assessment alone is unreliable and the consequences of misdiagnosis are serious. This guideline focuses on the identification of optimal strategies for the diagnosis of DVT in ambulatory adults.


METHODS
The methods of this guideline follow those described in Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines.


RESULTS
We suggest that clinical assessment of pretest probability of DVT, rather than performing the same tests in all patients, should guide the diagnostic process for a first lower extremity DVT (Grade 2B). In patients with a low pretest probability of first lower extremity DVT, we recommend initial testing with D-dimer or ultrasound (US) of the proximal veins over no diagnostic testing (Grade 1B), venography (Grade 1B), or whole-leg US (Grade 2B). In patients with moderate pretest probability, we recommend initial testing with a highly sensitive D-dimer, proximal compression US, or whole-leg US rather than no testing (Grade 1B) or venography (Grade 1B). In patients with a high pretest probability, we recommend proximal compression or whole-leg US over no testing (Grade 1B) or venography (Grade 1B).


CONCLUSIONS
Favored strategies for diagnosis of first DVT combine use of pretest probability assessment, D-dimer, and US. There is lower-quality evidence available to guide diagnosis of recurrent DVT, upper extremity DVT, and DVT during pregnancy.
Department of Medicine, McMaster University and Thrombosis and Atherosclerosis Research Institute, Hamilton, ON, Canada. Electronic address: batesm@mcmaster.ca.
Shannon M
SM
Bates
Departments of Medicine and Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada.
Roman
R
Jaeschke
Department of Medicine, Intermountain Medical Center, Murray, UT.
Scott M
SM
Stevens
School of Health and Related Research, University of Sheffield, Sheffield, England.
Steven
S
Goodacre
Department of Medicine, University of Ottawa, Ottawa, ON, Canada.
Philip S
PS
Wells
School of Health and Related Research, University of Sheffield, Sheffield, England.
Matthew D
MD
Stevenson
Departments of Medicine and Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada.
Clive
C
Kearon
Departments of Medicine and Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada.
Holger J
HJ
Schunemann
Department of Medicine, McMaster University and Thrombosis and Atherosclerosis Research Institute, Hamilton, ON, Canada.
Mark
M
Crowther
Department of Medicine, Tufts New England Medical Center, Boston, MA.
Stephen G
SG
Pauker
Department of Medicine, University of Buffalo, Buffalo, NY.
Regina
R
Makdissi
Departments of Medicine and Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada.
Gordon H
GH
Guyatt
D000328:Adult; D000553:Ambulatory Care; D019317:Evidence-Based Medicine; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000032:analysis; D005343:Fibrinolytic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D006470:Hemorrhage / Q000097:blood / Q000139:chemically induced / Q000517:prevention & control; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods; D008297:Male; D010690:Phlebography / Q000379:methods; D011237:Predictive Value of Tests; D011336:Probability; D011655:Pulmonary Embolism / Q000175:diagnosis / Q000188:drug therapy / Q000517:prevention & control; D012307:Risk Factors; D012955:Societies, Medical; D013927:Thrombosis / Q000175:diagnosis* / Q000188:drug therapy* / Q000517:prevention & control; D014057:Tomography, X-Ray Computed / Q000379:methods; D014463:Ultrasonography / Q000379:methods; D014481:United States; D020246:Venous Thrombosis / Q000175:diagnosis* / Q000188:drug therapy* / Q000517:prevention & control
D005338:Fibrin Fibrinogen Degradation Products; D005343:Fibrinolytic Agents; C036309:fibrin fragment D