Stroke has characterized cardioembolic stroke as an important clinical entity, because it is the most common cause of death in cases of acute ischemic stroke. [1][2][3] Transesophageal echocardiography (TEE) is accepted as a crucial investigation for detecting the thromboembolic source and determining stroke subtype. However, it is sometimes difficult to make a diagnosis because of the splashing and vanishing of the intracardiac source of the emboli. [4][5][6][7][8][9][10][11][12] In patients with cardioembolic stroke it is necessary to carefully examine the intracardiac hypercoagulable state based on echocardiographic findings and/or serum sensitive markers, and then use this information to prevent recurrent attacks.It is well known that the left atrial appendage (LAA) is a major thromboembolic source in cardioembolic stroke. 7,8 Many clinical reports have shown a close relationship between LAA thrombus formation and left atrial mechanical remodeling, based on echocardiographic findings such as the presence of spontaneous echo contrast or a progressive Circulation Journal Vol.70, August 2006 reduction in LAA emptying flow velocity. 6,10,12,13 Serum fibrin monomer (FM) is a precursor of the fibrin polymer that is produced by the thrombin-mediated resolution of fibrinopeptide A from fibrinogen. In vivo, compared with fibrin polymer and stable fibrin, FM is fragile as a result of fibrinolysis. Therefore, it is thought to be a sensitive marker of a hypercoagulable state. 14,15 It has been reported that the measurement of serum FM level is a useful screening tool for identifying older individuals at increased risk of ischemic stroke. 16,17 The goal of this study was to investigate the association of serum FM level with LAA flow pattern alteration and thrombus formation in order to establish whether the serum level of FM is a sensitive screening tool for diagnosing stroke subtypes in the acute stroke care unit.
Methods
Study PatientsAmong 237 consecutive patients with acute cerebral infarction, 204 satisfied all of the following criteria: (1) abrupt stroke onset while awake with a maximal neurological deficit, (2) admission within 24 h of symptom recognition, (3) underwent measurement of serum coagulation and fibrinolytic activity on admission, (4) underwent TEE within 7 days of onset, (5) did not received oral administration of warfarin and/or treatment by intravenous infusion of thrombolytic agents or heparin, and (6) Background It is sometimes difficult to make a diagnosis of cardioembolic stroke in the stroke care unit, because of the splashing and vanishing of the intracardiac source of the emboli on transesophageal echocardiography. Serum fibrin-monomer (FM) is a new marker for coagulation activity that is useful for identifying older individuals at increased risk of ischemic stroke.
Methods and ResultsTwo hundred and four patients with acute ischemic stroke were examined for serum coagulation and fibrinolytic activity on admission, and underwent transesophageal echocardiography within 7 days of onset. Serum l...