Relationship Between Infarct Volume and Prothrombin Time-International Normalized Ratio in Ischemic Stroke Patients With Nonvalvular Atrial Fibrillation.

BACKGROUND In Japan, warfarin treatment at prothrombin time-international normalized ratio (PT-INR) of 1.60-2.60 is recommended for elderly patients with nonvalvular atrial fibrillation (NVAF). But it remains unknown whether PT-INR 1.60-1.99 has a similar effect on stroke severity as a value >2.0. The purpose of this study was to clarify the association between infarct volume and PT-INR levels.Methods and Results:The 180 patients (mean age, 76 years [SD, 10 years], 53% male) selected from 429 consecutive ischemic stroke patients admitted within 48 h of onset between 2004 and 2014 with NVAF were included. We classified them into 4 groups according to their PT-INR values on admission: no warfarin (NW), 129 patients; PT-INR <1.60 (poor control: PC), 29 patients; PT-INR 1.60-1.99 (low-intensity control: LC), 14 patients; and PT-INR ≥2.00 (high-intensity control: HC), 8 patients. Median (interquartile range: IQR) of infarct volume was 55 mL (IQR 14-175) in the NW, 42 mL (IQR 27-170) in the PC, 36 mL (IQR 6-130) in the LC, and 11 mL (IQR 0-39) in the HC groups. The infarct volume of the HC group was significantly smaller than in the other 3 groups, but no difference existed between the LC and PC groups or the LC and NW groups. CONCLUSIONS Warfarin control at PT-INR of 1.60-1.99 is not effective for reducing the severity of ischemic stroke in NVAF patients.

[1]  J. Kira,et al.  Pre-admission CHADS2, CHA2DS2-VASc, and R2CHADS2 Scores on Severity and Functional Outcome in Acute Ischemic Stroke with Atrial Fibrillation. , 2015, Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association.

[2]  M. Ezekowitz,et al.  2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: a report of the American College of Cardiology/American Heart Association Task Force on practice guidelines and the Heart Rhythm Society. , 2014, Circulation.

[3]  M. Ezekowitz,et al.  2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation: executive summary: a report of the American College of Cardiology/American Heart Association Task Force on practice guidelines and the Heart Rhythm Society. , 2014, Circulation.

[4]  Y. Chun,et al.  Inappropriate use of oral anticoagulants for patients with atrial fibrillation. , 2014, Circulation journal : official journal of the Japanese Circulation Society.

[5]  A. Brandes,et al.  Preadmission Oral Anticoagulant Treatment and Clinical Outcome Among Patients Hospitalized With Acute Stroke and Atrial Fibrillation: A Nationwide Study , 2014, Stroke.

[6]  J. Hata,et al.  Intensity of Anticoagulation and Clinical Outcomes in Acute Cardioembolic Stroke: The Fukuoka Stroke Registry , 2013, Stroke.

[7]  I. Kubota,et al.  Target international normalized ratio values for preventing thromboembolic and hemorrhagic events in Japanese patients with non-valvular atrial fibrillation: results of the J-RHYTHM Registry. , 2013, Circulation journal : official journal of the Japanese Circulation Society.

[8]  Jeroen J. Bax,et al.  2012 focused update of the ESC Guidelines for the management of atrial fibrillation: an update of the 2010 ESC Guidelines for the management of atrial fibrillation. Developed with the special contribution of the European Heart Rhythm Association. , 2012, European heart journal.

[9]  A. Villringer,et al.  Impact of Anticoagulation before Stroke on Stroke Severity and Long-Term Survival , 2012, International journal of stroke : official journal of the International Stroke Society.

[10]  T. Yoshimine,et al.  Preadmission Therapeutic Anticoagulation Reduces Cerebral Infarct Volume in Patients with Nonvalvular Atrial Fibrillation , 2011, European Neurology.

[11]  K. Furie,et al.  Admission international normalized ratio and acute infarct volume in ischemic stroke , 2008, Annals of neurology.

[12]  Y. Shinohara,et al.  Outline of the Japanese Guidelines for the Management of Stroke 2004 and Subsequent Revision , 2008, International journal of stroke : official journal of the International Stroke Society.

[13]  G. Guyatt,et al.  Preadmission antithrombotic treatment and stroke severity in patients with atrial fibrillation and acute ischaemic stroke: an observational study , 2006, The Lancet Neurology.

[14]  K. Minematsu,et al.  Optimal intensity of international normalized ratio in warfarin therapy for secondary prevention of stroke in patients with non-valvular atrial fibrillation. , 2001, Internal medicine.

[15]  Martha J. Radford,et al.  Validation of Clinical Classification Schemes for Predicting Stroke: Results From the National Registry of Atrial Fibrillation , 2001 .

[16]  W. J. Hamilton,et al.  Adjusted-dose warfarin versus low-intensity, fixed-dose warfarin plus aspirin for high-risk patients with atrial fibrillation: Stroke Prevention in Atrial Fibrillation III randomised clinical trial , 1996, The Lancet.

[17]  T. Minamino,et al.  Dynamic process between the clotting and the lytic activities on intracardiac thrombi--its relationship with systemic embolization. , 1992, Japanese circulation journal.

[18]  T Brott,et al.  Measurements of acute cerebral infarction: lesion size by computed tomography. , 1989, Stroke.

[19]  Gerhard Hindricks,et al.  2012 focused update of the ESC Guidelines for the management of atrial fibrillation: an update of the 2010 ESC Guidelines for the management of atrial fibrillation--developed with the special contribution of the European Heart Rhythm Association. , 2012, Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology.