Clinical characteristics of italian patients with venous thromboembolism enrolled in the RIETE Registry

Introduction: The clinical characteristics, treatment strategies and outcome of patients with venous thromboembolism (VTE) may vary from country to country.
Materials and methods: The RIETE (Registro Informatizado su la Enfermedad TromboEmbolica) is an ongoing, prospective registry of consecutive patients with acute, objectively confirmed, symptomatic VTE. Our aim was to assess the influence of surgery and immobility for non-surgical reasons on 3-month outcomes of all Italian patients registered in the RIETE.
Results: Through July 2008, 21,397 patients with acute VTE were registered in the RIETE. Of these, 896 (4.2%) were Italian, and 360 (40%) presented with pulmonary embolism (PE). Overall, 137 (15%) developed VTE after surgery; 156 (17%) developed VTE after >4 days of immobility, and 603 (67%) developed VTE in the absence of surgery or immobility. Most patients (83%) received initial therapy with low-molecular-weight heparin; 15% received unfractionated heparin. For long-term therapy, 63% of patients received vitamin K antagonists. The incidence of fatal PE during the first 3 months of therapy was 1.5% for patients with postoperative VTE, 7.7% for who developed VTE after immobility, and 1.2% for the remaining patients. The incidence of fatal bleeding among these patients was 1.5%, 1.9% and 0.3%, respectively. Of the 137 patients with postoperative VTE, 61% had received VTE prophylaxis. Of the 156 patients with recent immobility, 24% had received VTE prophylaxis.
Conclusions: VTE arising after a period of immobility was associated with the highest rates of fatal PE and fatal bleeding during the first 3 months of therapy. The use of thromboprophylaxis in this population should be improved.