Venous Thromboembolic Disease and Pregnancy

To the Editor: In their review article on venous thromboembolic disease during pregnancy, Marik and Plante (Nov. 6 issue) 1 recommend the use of compression ultrasonography as the initial test for pulmonary embolism. However, in nonpregnant patients, compression ultrasonography is not recommended by either the American Thoracic Society 2 or the British Thoracic Society 3 as the initial workup for pulmonary embolism in patients without leg symptoms because of the unacceptably low predictive value of positive findings (PPV). The PPV of compression ultrasonography is unknown in pregnancy and may be lower than that in nonpregnant women because leg swelling and low flow on . . .