Risk Factors for Venous Thromboembolism
Until the 1990s, venous thromboembolism (VTE) was viewed primarily as a complication of hospitalization for major surgery (or associated with the late stage of terminal illness). However, recent trials in patients hospitalized with a wide variety of acute medical illnesses have demonstrated a risk of VTE in medical patients comparable with that seen after major general surgery. In addition, epidemiologic studies have shown that between one quarter and one half of all clinically recognized symptomatic VTEs occur in individuals who are neither hospitalized nor recovering from a major illness. This expanding understanding of the population at risk challenges physicians to carefully examine risk factors for VTE to identify high-risk patients who could benefit from prophylaxis.
Natural History of Venous Thromboembolism
Most deep vein thromboses (DVTs) start in the calf, and most probably resolve spontaneously. Thrombi that remain confined to the calf rarely cause leg symptoms or symptomatic pulmonary embolism (PE). The probability that calf DVT will extend to involve the proximal veins and subsequently cause PE increases with the severity of the initiating prothrombotic stimulus. Although acute venous thromboembolism (VTE) usually presents with either leg or pulmonary symptoms, most patients have thrombosis at both sites at the time of diagnosis. Proximal DVTs resolve slowly during treatment with anticoagulants, and thrombi remain detectable in half of the patients after a year. Resolution of DVT is less likely in patients with a large initial thrombus or cancer. About 10% of patients with symptomatic DVTs develop severe post-thrombotic syndrome within 5 years, and recurrent ipsilateral DVT increases this risk. About 10% of PEs are rapidly fatal, and an additional 5% cause death later, despite diagnosis and treatment. About 50% of diagnosed PEs are associated with right ventricular dysfunction, which is associated with a ≈5-fold greater in-hospital mortality. There is ≈50% resolution of PE after 1 month of treatment, and perfusion eventually returns to normal in two thirds of patients. About 5% of treated patients with PE develop pulmonary hypertension as a result of poor resolution. After a course of treatment, the risk of recurrent thrombosis is higher (ie, ≈10% per patient-year) in patients without reversible risk factors, in those with cancer, and in those with prothrombotic biochemical abnormalities such as antiphospholipid antibodies and homozygous factor V Leiden.
The Epidemiology of Venous Thromboembolism
Venous thromboembolism (VTE) occurs for the first time in ≈100 persons per 100,000 each year in the United States, and rises exponentially from <5 cases per 100,000 persons <15 years old to ≈500 cases (0.5%) per 100,000 persons at age 80 years. Approximately one third of patients with symptomatic VTE manifest pulmonary embolism (PE), whereas two thirds manifest deep vein thrombosis (DVT) alone. Despite anticoagulant therapy, VTE recurs frequently in the first few months after the initial event, with a recurrence rate of ≈7% at 6 months. Death occurs in ≈6% of DVT cases and 12% of PE cases within 1 month of diagnosis. The time of year may affect the occurrence of VTE, with a higher incidence in the winter than in the summer. One major risk factor for VTE is ethnicity, with a significantly higher incidence among Caucasians and African Americans than among Hispanic persons and Asian-Pacific Islanders. Overall, ≈25% to 50% of patient with first-time VTE have an idiopathic condition, without a readily identifiable risk factor. Early mortality after VTE is strongly associated with presentation as PE, advanced age, cancer, and underlying cardiovascular disease.
Right Atrial Myxoma Complicated by Pulmonary Thromboembolism: A Case Report and Review of Literature
Primary cardiac tumors are rare with myxoma being the most common benign cardiac tumor. They are usually sporadic, affecting left atrium and frequently occur in women. They are known to cause valvular obstruction, thromboembolism and arrhythmias. We present a case of right atrial myxoma complicated by pulmonary embolism. The atrial myxoma was diagnosed on autopsy.
Non-pharmacological Prophylaxis of Venous Thromboembolism in Acutely Ill Medical Patients
Venous thromboembolism (VTE) represents one of the leading causes of mortality and morbidity in acutely ill medical patients. VTE prophylaxis can be assured by pharmacological strategies and, when contraindicated, by non pharmacological measures, such as early mobilization, graduated compression stockings (GCS), intermittent pneumatic compression (IPC) or inferior vena caval filters. Literature evidence on non pharmacological VTE prophylaxis lacks and guidelines are not standardized for hospitalized ill medical patients. Much recently randomized clinical trials in patients with stroke and other medical diseases, seem to increase doubts and reduce certainties in this context. In this review we provide information about non pharmacological thromboprophylaxis in acutely hospitalized ill medical patients.
 Anderson Jr, F.A. and Spencer, F.A., 2003. Risk factors for venous thromboembolism. Circulation, 107(23_suppl_1), pp.I-9.
 Kearon, C., 2003. Natural history of venous thromboembolism. Circulation, 107(23_suppl_1), pp.I-22.
 White, R.H., 2003. The epidemiology of venous thromboembolism. Circulation, 107(23_suppl_1), pp.I-4.
 Kundu, R., Punia, R.S., Arora, S. and Mohan, H., 2014. Right Atrial Myxoma Complicated by Pulmonary Thromboembolism: A Case Report and Review of Literature. Cardiology and Angiology: An International Journal, pp.298-303.
 Masotti, L., Di Napoli, M., Lorenzini, G., Godoy, D.A., Cappelli, R., Panigada, G., Bettoni, N. and Landini, G., 2014. Non-pharmacological Prophylaxis of Venous Thromboembolism in Acutely Ill Medical Patients. Cardiology and Angiology: an International Journal, pp.1-14.