Comparative study of atrial vulnerability in patients with unexplained ischemic stroke or lone atrial paroxysmal fibrillation.
Strokes have a high prevalence, with a high rate of recurrence, and about 30-40% remain of unknown cause. Some patients might have asymptomatic paroxysmal atrial fibrillation (AF) which remains the main cause of embolic events. A latent atrial arrhythmogenic substrate may induce recurrent arrhythmias, including functional abnormalities such as nonuniform refractoriness and/or anatomic abnormalities such as atrial septum aneurysm (ASA) and patent foramen ovale (PFO). In 175 patients divided into three groups (Group I: 103 patients with unexplained ischemic stroke, Group II: 48 patients with paroxysmal AF and Group III or control group: 24 patients explored for another cause), such an atrial arrhythmogenic substrate was assessed by electrophysiological study. Groups I and II had a similar high rate of inducible atrial arrhythmias compared to control group III where no arrhythmia was induced. An induced atrial arrhythmia was observed in more than 50% of patients of Group I and in more than 70% of patients of Group II without any significant difference according to age. However, in 26 young patients of Group I who had a transesophageal echocardiography, both a high rate (46%) of ASA and/or PFO and a frequent latent atrial vulnerability (LAV) were observed, compared to older patients where an atrial septum abnormality was observed in only 21% of cases. Thus, among patients with stroke of unknown cause, a high percentage of them might have asymptomatic atrial paroxysmal arrhythmia. The predictive value of the electrophysiological study for spontaneous arrhythmias and recurrence of stroke remains to be demonstrated.
Rouesnel
P
P
Department of Cardiology, General Hospital, Vendôme, France. lfau@med.univ-tours.fr
Babuty
D
D
Fauchier
L
L
Saudeau
D
D
Hurreesing
R
R
Cosnay
P
P
Garnier
L F
LF
D001281:Atrial Fibrillation / Q000150:complications* / Q000503:physiopathology; D002545:Brain Ischemia / Q000209:etiology* / Q000503:physiopathology; D004594:Electrophysiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D020521:Stroke / Q000209:etiology* / Q000503:physiopathology