Is occult atrial disorder a frequent cause of non-hemorrhagic stroke? Long-term ECG in 86 patients.

To assess the importance of occult atrial disorder with possible embolization as a cause of non-hemorrhagic stroke, 68 patients with neurologic symptoms lasting 24 hours or more and 18 patients with transient ischemic attacks were examined by long-term electrocardiographic recording (LTER). Lacking matched controls we used a reference population of 103 elderly subjects selected at random from the general population for a previous LTER study. Permanent or episodic atrial arrhythmias of types known to cause cerebral embolization were detected by LTER in 32 (47%) of the 68 patients with a clinical diagnosis of cerebral embolization or thrombosis and in 6 (33%) of the 18 patients with transient ischemic attacks. Of the 38 patients with atrial arrhythmia during LTER 17 had such arrhythmias in their standard ECGs. This frequency of atrial arrhythmias during LTER differs from that of the reference population (p less than 0.025). Thirteen of 16 patients with multiple cerebral lesions had signs of atrial arrhythmia during LTER. Patients having occult atrial disorder with episodic atrial arrhythmia may be an important and common risk group for non-hemorrhagic stroke in addition to the previously recognized group of patients with atrial arrhythmia detectable in the standard ECG. LTER may be important in the evaluation of patients with unexplained stroke.