Naritoku Dean K, Casebeer Doris J, Darbin Olivier
Neurology and Pharmacology, Southern Illinois University, School of Medicine, Springfield, Illinois 62794, USA.
Epilepsia. 2003 Jul;44(7):912-6. doi: 10.1046/j.1528-1157.2003.48302.x.
Human epilepsy is associated with abnormalities in cardiac regulation, as measured by reductions of heart rate variability (HRV) and approximate entropy (ApEn), but it is not known how these abnormalities are related to seizure experience.
Baseline electrocardiogram (ECG) was recorded from seizure-naive rats. They were subjected daily to maximal electroshock (MES), which induced tonic seizures with hindlimb extension, for a total of 10 days. ECG was obtained for 30 min before and after the first and last seizure. R-R variability, spectral variability, and ApEn were calculated to determine changes in pre- and postictal cardiac regulation. Before the last seizure, interictal parameters were compared with baseline values to determine changes in interictal HRV as a consequence of seizure repetition. Postictal values obtained after the last seizure were compared with the initial postictal data to look for changes in postictal cardiac regulation.
During the postictal state, a mild, but significant, loss of ApEn was present after either the first or last seizure. Seizure repetition induced loss of R-R variability and high-frequency spectral band, which was present both interictally and postictally.
The results suggest that convulsive seizures are associated with an immediate reduction of the complexity of cardiac rhythm regulation, as reflected by reductions of ApEn. Seizure repetition may induce long-term neural abnormalities in neurocardiac regulatory systems, especially parasympathetic, which limit appropriate autonomic responses. These acquired abnormalities may, in turn, predispose individuals to cardiac arrhythmia and sudden unexpected death in epilepsy.
通过心率变异性（HRV）和近似熵（ApEn）降低来衡量，人类癫痫与心脏调节异常有关，但尚不清楚这些异常与癫痫发作经历之间的关系。
记录未发作过癫痫的大鼠的基线心电图（ECG）。每天对它们进行最大电休克（MES），诱导后肢伸展的强直发作，共持续10天。在第一次和最后一次发作前30分钟和发作后30分钟获取心电图。计算R-R变异性、频谱变异性和ApEn，以确定发作前和发作后心脏调节的变化。在最后一次发作前，将发作间期参数与基线值进行比较，以确定由于发作重复导致的发作间期HRV的变化。将最后一次发作后获得的发作后值与初始发作后数据进行比较，以寻找发作后心脏调节的变化。
在发作后状态下，第一次或最后一次发作后均出现ApEn轻度但显著降低。发作重复导致R-R变异性和高频频段丧失，发作间期和发作后均存在。
结果表明，惊厥性发作与心律调节复杂性的立即降低有关，表现为ApEn降低。发作重复可能在神经心脏调节系统，尤其是副交感神经系统中诱发长期神经异常，限制适当的自主反应。这些获得性异常反过来可能使个体易患心律失常和癫痫猝死。
