Prevalence of deep vein thrombosis in suspected and proven pulmonary embolism: a meta-analysis.

The purpose of this study was to determine the prevalence of lower extremity deep venous thrombosis (DVT) in patients with suspected and proven pulmonary embolism (PE). A meta-analysis was performed, based on literature from January 1983 to June 1997. Papers obtained from a computer-aided literature search were divided into studies with pulmonary angiography or ventilation-perfusion (V/Q) scintigraphy as the reference study. Our own observational data of the prevalence of DVT in 149 patients suspected of PE were also reported. The estimated prevalence of DVT in patients with proven and suspected PE was calculated. In the 149 patients studied, the prevalence of DVT was 12% with suspected PE and 32% (95% confidence interval 20-46%) in patients with proven PE. The individual studies showed a considerable heterogeneity, the prevalence of DVT in proven PE ranged from 10 to 93%. The pooled estimate of the prevalence of DVT in patients suspected of PE, over all studies, was 18% (95% confidence interval 15-20%). The DVT prevalence in proven PE was 36% (95% confidence interval 22-52%) in the angiography-based studies, and 45% (95% confidence interval 33-58%) in the V/Q scintigraphy-based studies. In conclusion, the current meta-analysis shows that the prevalence of DVT in suspected PE is approximately 18%, and in proven PE 36-45%.