[Cardiac arrhythmias in Guillain-Barre syndrome. An overview of the diagnosis of a rare but potentially life-threatening complication].

Autonomic neuropathy is an important complication of Guillain-Barré syndrome (GBS). In particular, over-reactivity of vagal function may lead to serious cardiac disturbances ranging from bradycardia to asystole. Early recognition of these events is essential for appropriate intervention such as the insertion of a cardiac pacemaker. Recent studies indicate that serious bradyarrhythmias could be observed in severely and even less severely affected patients who were still able to walk more than 5 meters. Conventional measures such as the presence of tachycardia, heart rate and blood pressure fluctuations, or short-term heart rate variability and standardized autonomic function tests were not useful in predicting serious bradyarrhythmias. However, abnormal sensitivity to eyeball pressure testing correctly identified two of three patients who needed cardiac pacing or cardiopulmonary resuscitation due to heart arrest; eight of ten patients without bradyarrhythmic events showed normal responses. New methods such as the 24-hour heart rate power spectrum may yield sensitive and specific markers for assessing the risk of impending and potentially life-threatening arrhythmias in patients with GBS.