Table 5.

Results that “rule-in” or “rule-out” PE

Results
Diagnostic for PE
CTPA
Intraluminal filling defect in a lobar or main pulmonary artery
Intraluminal filling defect in a segmental pulmonary artery AND moderate or high CPTP
V/Q scan
High-probability scan AND moderate or high CPTP
Positive diagnostic test for DVT (with a nondiagnostic V/Q scan or CTPA, or scan not done)
Rules-out PE
CTPA
Negative good quality scan
Perfusion scan (usually part of V/Q scan)
Normal
D-dimer
Negative very sensitive test (eg, D-dimer <500 μg/L) AND low or moderate CPTP
Negative moderately sensitive test AND low CPTP
In patients over 50 y, D-dimer level <10 times the patient's age AND a low or moderate CPTP
Nondiagnostic V/Q scan or CTPA AND normal proximal venous US AND one of:
Low CPTP
Negative moderately or very sensitive D-dimer test
Normal repeat proximal US after 7 d and 14 d