title: Blood flow in the left atrial appendage and embolic stroke in nonvalvular atrial fibrillation.
abstract: It is unclear if low flow velocity in the left atrial appendage (LAA) is a predisposing factor to stroke in patients with nonvalvular atrial fibrillation (NVAF). We investigated flow velocity in the LAA in NVAF patients in relation to a past history of stroke and other potential embolic sources. We measured and analyzed peak flow velocities into (FV-in) and out of (FV-out) the LAA in a middle portion of the LAA in 35 NVAF patients by transesophageal echocardiography (TEE). We divided the NVAF patients into 3 groups: the Eaf group had a history of embolic stroke without any other potential embolic sources; the Emulti group had other potential embolic sources, and the control group had no embolic history. FV-in and FV-out in the Eaf group (12.3 +/- 6.7 and 10.2 +/- 7.3 cm/s) were significantly lower than those in the control group (24.3 +/- 11.3 and 19.9 +/- 8.8 cm/s; multicomparison Scheffé's test, p = 0.0123 and 0.0395, respectively). The Emulti group varied in those values from less than 5 to above 35. Low flow velocity in the LAA seems to be a predisposing factor for stroke in NVAF patients without any other sources of emboli.
authors.affiliation: Cerebrovascular Division, Department of Medicine, National Cardiovascular Center, Suita, Japan. cds99051@syd.odn.ne.jp
authors.forename: T
authors.initials: T
authors.lastname: Takada
authors.forename: M
authors.initials: M
authors.lastname: Yasaka
authors.forename: K
authors.initials: K
authors.lastname: Nagatsuka
authors.forename: K
authors.initials: K
authors.lastname: Minematsu
authors.forename: T
authors.initials: T
authors.lastname: Yamaguchi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D020517:Atrial Appendage / Q000000981:diagnostic imaging*; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging*; D001783:Blood Flow Velocity / Q000502:physiology; D017548:Echocardiography, Transesophageal; D005260:Female; D006801:Humans; D020766:Intracranial Embolism / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors