Cardiac effects of rapid intravenous loading of lacosamide in patients with epilepsy.

BACKGROUND

Lacosamide (LCM) is a new antiseizure medication, and intravenous (IV) loading of LCM is recently used against status epilepticus. IV loading of LCM is usually well-tolerated; however, there are concerns about LCM-induced serious adverse cardiac events. This study was aimed at investigating whether rapid IV loading of LCM is associated with adverse cardiac or hemodynamic events in cases of epilepsy emergencies in real-world settings.

METHODS

We reviewed medical records of consecutive adult epilepsy patients who received a single loading dose (400 mg) of IV LCM between January 2019 and December 2020 and included patients who exhibited status epilepticus or acute repetitive seizures. Electrocardiography findings, blood pressure, and heart rate before and after the IV infusion of LCM were collected.

RESULTS

Of the 85 patients included, 32.9 % (28/85 patients) had experienced at least one cardiac adverse event. The most common adverse events were new-onset first-degree atrioventricular block (19 patients) and hypotension (seven patients). Atrial fibrillation and bradycardia developed in two patients and atrial flutter in one. There were significant increases in the mean PR interval (from 169.3 msec to 184.5 msec, P < 0.01) and decreases in the mean heart rate (from 91.7 to 86.9, P = 0.01) after IV loading of LCM. Older age was significantly associated with a higher magnitude of the PR interval difference between before and after IV loading of LCM.

CONCLUSIONS

In cases of epilepsy emergencies, adverse cardiac events commonly developed after IV loading of LCM, although most adverse events were mild in severity or not clinically significant. Elderly patients or patients with underlying cardiac diseases were prone to exhibiting a more prolonged PR interval after IV loading of LCM. Thus, the loading dose of IV LCM should be infused under careful ECG monitoring in these patients.