A Study on the Prevalence of Heparin-Induced Thrombocytopenia in Cardiovascular Patients

Several clinical studies in Western countries have revealed that the prevalence of HIT is 0.5 to 5%, varying depending on the clinical setting. Thirty to 50% of HIT patients suffer from thromboembolic events, and the mortality of HIT is 10 to 20%. In contrast, many physicians in Japan report no experience in treating HIT, although approximately 200,000 patients per year receive heparin. This raises the possibility that the prevalence of HIT might be much lower in Japan than in Western countries. In fact, neither the drug for HIT treatment nor the laboratory test for HIT diagnosis has been approved by the Pharmaceutical Affairs Law in Japan. We have therefore conducted a multi-center, prospective cohort study to determine the prevalence and profile of HIT in patients undergoing cardiovascular surgery or percutaneous coronary intervention. Approximately 1,500 patients will be enrolled in this study.