Reduced cardiac function and risk of venous thromboembolism in Asian countries.

Patients with reduced cardiac function are thought to have a higher risk of venous thromboembolism (VTE). Additionally, they are vulnerable to complications of pulmonary embolism (PE) as well as right heart failure (HF), which in return is supposed to increase the rate of mortality. Studies focusing on VTE in heart failure patients were rare in Asian countries before the 21st century. Nowadays, more and more data are becoming available in this field in Asia. It is already known that heart failure can increase the risk of VTE, but so far a consensus on this issue has not been reached for many years, not only in Asian countries but all over the world. This condition may be due to the detailed pathological advancement in Virchow's triad and some other theories. In clinical practice, VTE, especially PE is difficult to diagnose in patients with heart failure because of overlapping symptoms (e.g. cough and chest pain) and the elevation of laboratory markers (e.g. probrain natriuretic peptide (NT-proBNP) and D-dimer in both heart failure and VTE patients). Management of VTE in heart failure patients is also controversial because heart failure patients always have complications, such as renal failure and hepatic failure, which increase the risk of bleeding. In this study, we analyzed data from China, Japan, Korea, Singapore and India mainly to get a better understanding of the research progress in VTE in patients with heart failure. The aim of this review is to discuss the risk, incidence, advancement of diagnosis, management and prevention of VTE in patients with heart failure in Asian countries.