High Thrombin Generation after Acute Ischemic Stroke or Transient Ischemic Attack Is Associated with a Reduced Risk of Recurrence: An Observational Cohort Study.

Thrombin is increasingly recognized to be of importance for cardiovascular disease. The aim of this study was to investigate the prognostic value of thrombin generation variables in a cohort of patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA). Thrombin generation potential measured by calibrated automated thrombogram (CAT) and prothrombin fragment F1 + 2 was determined in the acute and convalescent phases for a cohort of 190 patients with AIS/TIA. Microvesicle (MV)-induced thrombin generation potential was determined for a subset of patients using modified CAT. Primary outcome was a composite of fatal and nonfatal AIS or myocardial infarction as documented in Swedish registers during a total follow-up of 986 patient-years. Hazard ratios (HRs) were calculated using Cox regression based on variable median split. Peak thrombin and endogenous thrombin potential (ETP) above median in the acute phase were associated with a reduced risk of primary outcome after adjustment for cardiovascular risk factors, HR: 0.50 (0.27-0.92), p = 0.026 and HR: 0.53 (0.28-0.99), p = 0.048, respectively. F1 + 2 was lower in patients than in healthy controls but not associated with outcome. MV-induced peak thrombin above median in the acute phase was associated with recurrent AIS, unadjusted HR: 2.65 (1.03-6.44), p = 0.044. Contrary to expectation, high thrombin generation potential is associated with a reduced risk of recurrent ischemic event in patients with AIS/TIA. Low ETP/peak thrombin combined with high MV-induced peak thrombin can potentially identify patients at high risk of recurrence.

Improved screening for silent atrial fibrillation after ischaemic stroke.

OBJECTIVES: To what extent silent paroxysmal atrial fibrillation (AF) is present in ischaemic stroke patients has not been established. We hypothesized that brief intermittent long-term electrocardiogram (ECG) recordings at regular time intervals are more effective than short-term continuous ECG monitoring in detecting silent AF episodes. METHODS AND RESULTS: Consecutive patients who had suffered an ischaemic stroke/transient ischaemic attack (TIA) and were without known AF underwent a 24 h continuous ECG recording and performed 10 s rhythm registrations using a hand-held ECG recorder twice daily for 30 days and when arrhythmia symptoms occured. Two hundred and forty-nine stroke patients were included. Mean National Institute of Health Stroke Scale (NIHSS) score was 0.9 (0-10). In total, 17 patients were diagnosed with AF. One hundred and eight AF episodes were diagnosed in 15 patients using intermittent recording, out of which 22% where unscheduled symptom triggered episodes. In three patients AF was diagnosed with both methods and in two patients AF was detected exclusively with 24 h Holter monitoring. A significant difference in favour of the hand-held ECG was shown between the two methods (P = 0.013). The total prevalence of AF was 6.8% and increased to 11.8% in patients ≥75 years. No AF was found in patients <65 years. CONCLUSIONS: Prolonged brief intermittent arrhythmia screening substantially improves the detection of silent paroxysmal AF in patients with a recent ischaemic stroke/TIA, and thus facilitates the detection of patients who should receive oral anticoagulant treatment.