CHAPTER 37 Venous Thromboembolism
In this chapter, deep vein thrombosis (DVT) and pulmonary embolism (PE) are discussed as manifestations of the same disease process. Despite the steadily growing use of medical thromboprophylaxis, PE remains the third most frequent cause of cardiovascular mortality.The current concept of venous thromboembolism (VTE) is that of a multifactorial disease. Besides age, several transient and permanent risk factors have been recognized. The strongest in the former group are surgery and trauma, whereas the latter is dominated by active cancer and thrombophilia. However, a substantial proportion of cases present without an identifiable risk factor and are therefore classified as ‘idiopathic’ or ‘unprovoked’ episodes. In those patients, or in the presence of a permanent risk factor, VTE is a chronic relapsing disease.
The diagnosis of a current episode has to be based on the result of an imaging procedure. During the last 10 years, compression ultrasound and helical computed tomography have turned out to be the most powerful diagnostic tools. However, strategies have been developed to safely exclude the disease on the basis of clinical pre-test probability and D-dimer testing alone in one-third of all suspected cases.
For most patients anticoagulation is the only acute treatment modality. Subcutaneous low-molecular-weight heparins or fondaparinux represent the current standard of care. The post-thrombotic syndrome as the long-term sequela of DVT can be effectively prevented by compression therapy. Haemodynamic instability in PE requires systemic thrombolysis according to the risk of fatal right heart failure. Vitamin K antagonists remain the standard treatment for maintenance therapy, the duration of which has to be balanced between the risk of recurrence and the potential for major bleeding.
Chapter 28)
