“…This pool, however, should not be considered a biomarker of intravascular fibrin deposition and thrombus formation. It can be speculated that this might be one of the reasons why D-dimer is a useful biomarker in healthy ambulatory subjects suspected of VTE [ 5 ] and is of little value in those who are hospitalized and/or critically ill [ 6 ]. In the latter, such comorbidities as pneumonia, malignancy, congestive heart failure, etc., may increase D-dimer even in the absence of VTE.…”