Cardiac arrhythmias and sudden unexpected death in epilepsy: Results of long-term monitoring.

BACKGROUND: Cardiac rhythm and conduction disorders are common in patients with epilepsy and are presumably one of the leading causes of sudden unexpected death. There are only a few published reports on ictal cardiac arrhythmias detected by continuous monitoring, and the majority had a small sample size.

OBJECTIVE: The aim of this study was to evaluate the frequency and type of cardiac arrhythmias recorded by an implantable loop recorder in patients with drug-resistant epilepsy.

METHODS: We implanted a subcutaneous loop recorder to 193 patients with drug-resistant epilepsy. Automatic triggers to initiate cardiac rhythm recording were cardiac pauses of >3 seconds and any episodes of bradycardia (≤45 beats/min) or tachycardia (≥150 beats/min). Patients/relatives were instructed to begin peri-ictal rhythm recording by using an external activator device. The follow-up duration was 36 months, with scheduled follow-up visits every 3 months.

RESULTS: A total of 6494 electrocardiogram traces were recorded during the median follow-up of 36 months (interquartile range 3-36 months). Ictal heart rhythm and rate changes were detected in 143 patients (74%). The most common finding was ictal sinus tachycardia (66.8%). Sinus bradycardia was observed in 13 patients (6.7%). Three patients had clinically relevant cardiac pauses of >6 seconds, requiring permanent pacemaker implantation. Five patients (2.6%) died suddenly.

CONCLUSION: Ictal heart rhythm and rate changes occur in most of the patients with drug-resistant epilepsy. Clinically relevant cardiac events, related to ictal and postictal periods, are rare. No potentially malignant arrhythmias were detected in patients who died suddenly during the preceding follow-up period.