Hematologogical and Sonological Studies on Mechanisms of Thromboembolism in Non-Valvular Atrial Fibrillation

2001 Fiscal Year Final Research Report Summary

• Project/Area Number: 11670645
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Neurology
• Research Institution: Tokyo Women's Medical University
• Principal Investigator: UCHIYAMA Shinichiro Tokyo Women's Medical University, Department of Neurology, Professor, 医学部, 教授 (50119905)
• Co-Investigator(Kenkyū-buntansha): KASANUKI Hiroshi Tokyo Women's Medical University, Department of Neurology, Professor, 医学部, 教授 (40096574)
• Project Period (FY): 1999 – 2001
• Keywords: ATRIAL FIBRILLATION / CEREBRAL INFARCTION / BLOOD COAGULATION MARKERS / RISK FACTORS / ANTITHROMBOTIC THERAPY / WARFARIN / INR / PROGNOSIS

Research Abstract

In patients with non-valvular atrial fibrillation (NVAF), who had cerebral embolism, beta-thromboglobulin, platelet factor 4, and thrombin-antithrombin-III (TAT) were increased in acute phase, while fibrin monomer and D-dimer (DD) were most increased in subacute phase. Platelet p-selectin expression and reticulated platelets were more frequently increased than platelet fibrinogen binding, and they were corrected by warfarin alone or with antiplatelet agents. Large infarcts and poor outcome at discharge were more frequent in patients with age more than 75 years, congestive heart failure, left atrial dilatation, and increased TAT and DD than in those without them. Large infarcts were more frequent in patients not treated with any antithrombotic agent than in those treated with warfarin. Among patients treated with warfarin, large infarcts were more frequent in INR below 2.0 than over 2.0, while major hemorrhage was more frequent in INR over 2.5 than below 2.5 among patients aged over 75 years. These results indicate that platelet and coagulation activation occur in acute phase followed by fibrinolysis activation in aubacute phase, platelet release and consumption occurs more easily than platelet aggregation, and aging, congestive heart failure, left atrial dilatation, coagulation-fibrinolysis activation, and no treatment with antithrombotic agents are risk factors for large infarcst and poor outocme, and optimal INR with warfarin treatmentm is 2.0 to 3.0 in patients aged below 75 years, while it is 2.0 to 3.0 in those aged over 75 years.