Asymptomatic Pulmonary Embolism Complicating Deep Venous Thrombosis

To the Editor. —The title of the article by Dr Moser and colleagues1more appropriately should have been "Frequent Abnormal Ventilation-Perfusion Scans in Patients With Deep Venous Thrombosis" to accurately reflect the results of the study. Their study was performed between 1987 and 1989 to evaluate the efficacy of tissue-type plasminogen activator for the treatment of thromboembolism. It was subsequently noted that 16 (43%) of 37 patients with deep venous thrombosis (DVT) had ventilation-perfusion (V/Q) scans with a high probability for pulmonary embolism (PE) although all patients were asymptomatic. Without any confirmatory pulmonary angiograms, the authors' conclusion that at least 43% of patients with bland DVT have asymptomatic PE is unsubstantiated. Assuming that these were not high-risk patients, the accuracy of V/Q scans under such circumstances is undocumented by other studies or by the authors. Although they assert that their scan scoring system is comparable to the high-probability category