Congestive heart failure's (CHF) contribution to the development of venous thromboembolism (VTE) has not been well explored in an outpatient population. We hypothesized that CHF would predispose outpatients to VTE. In a retrospective case-control study, we identified potential cases of deep venous thrombosis and pulmonary embolism in a 36-month period from the discharge database of a large urban Veterans Affairs' hospital. Controls were patients, matched for month of admission, with acute infection or diabetic complications. We applied stringent a priori definitions for CHF and outpatient VTE, reviewing discharge summaries and imaging studies for all patients as well as previous admissions when required. VTE status was assigned only if symptoms appeared before admission and a confirmatory objective study was obtained. CHF status required, at a minimum, a documented left ventricular ejection fraction (EF) of <45%, obtained before or within 3 months of the index presentation. Isolated mention of a past medical history of CHF was not sufficient. Two physicians blinded to study patient status independently determined whether each patient had CHF, through independent review of specially abstracted patient data. The prevalence of CHF was 18.4% in patients with VTE and 13.6% in controls. In a stepwise logistic regression model controlling for patient characteristics, CHF was an independent predictor of VTE: OR=2.6 (95% CI 1.4,4.7). Obesity, recent surgery, and prior VTE were also significant predictors of VTE. In an alternative model exploring the influence of EF, an EF<20% was a powerful predictor of VTE: OR=24.6 (95% CI 6.4,95.1). We conclude that outpatients with low LVEFs have markedly increased risk of DVT and PE and that the role of prophylactic anticoagulation in these patients needs to be seriously explored.
|Original language||English (US)|
|Journal||Journal of Investigative Medicine|
|State||Published - Feb 1999|
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)