Relation between ictal asystole and cardiac sympathetic dysfunction shown by MIBG-SPECT
Kerling F, Dütsch M, Linke R, Kuwert T, Stefan H, and Hilz MJ (2009) Relation between ictal asystole and cardiac sympathetic dysfunction shown by MIBG-SPECT. Acta Neurol Scand 120:2 123–9.
Abstract: OBJECTIVE: Tachyarrhythmias are common during epileptic seizures while bradyarrhythmias or asystoles are less frequent. Ictal asystole might be related to epilepsy-induced cardiac sympathetic denervation. METHODS: To evaluate cardiac post-ganglionic denervation in epilepsy patients with ictal asystoles we assessed I123-meta-iodobenzylguanidine (MIBG) as a marker of post-ganglionic cardiac norepinephrine-uptake, using single photon emission computed tomography (MIBG-SPECT). RESULTS: In five of 844 patients with presurgical video-electroencephalography-monitoring, we recorded ictal asystoles during nine of 37 seizures. Asystole patients underwent cardiologic examination (Holter-electrocardiogram, echocardiogram) and cardiac MIBG-SPECT. We compared cardiac MIBG uptake in the asystole patients to the uptake in 18 temporal lobe epilepsy (TLE) patients without bradyarrhythmias and in 14 controls without cardiac or neurological disease. As the cardiological examinations were unremarkable in all subjects, the heart/mediastinum-MIBG-uptake ratios (H/M-ratios) differed significantly between the three groups (P = 0.004). H/M-ratios were lower in asystole TLE patients (mean +/- SD: 1.58 +/- 0.3) than in patients without asystole (1.81 +/- 0.18; P = 0.037) or controls (1.96 +/- 0.16). CONCLUSIONS: Pronounced reduction in cardiac MIBG uptake of asystole patients indicates post-ganglionic cardiac catecholamine disturbance. Impaired sympathetic cardiac innervation limits adjustment and heart rate modulation, and may increase the risk of asystole and ultimately sudden unexpected death in epilepsy (SUDEP).
Keywords: asystole; temporal lobe epilepsy; cardiac MIBG-SPECT; sudden unexpected death in epilepsy; cardiac sympathetic denervation
- Original, prospective study of symapthetic nervous system input to the heart in epileptic patients with a history of asystole. Among 844 patients undergoing presurgical monitoring, 5 patients suffered a total of 37 seizures. All were adults and 4 of 5 were male, and all were on AED. The latency between seizure onset and asystole was 30 - 50 s, with aystole lasting 10 - 30 s. In the two seizure types that lateralized, left temporal and right temporal loci were observed. All suffered from TLE or MTLE. MIBG was used to infer the amount of norepinephrine taken up in the heart relative to the mediastinum, used as a background tissue. All temporal lobe epilepsy patients (5 with asystole and 18 without) had a trend for a lower uptake ratio than controls, and asystole patients were significantly lower than the other two groups.