Severe autonomic nervous system imbalance in Lennox-Gastaut syndrome patients demonstrated by heart rate variability recordings.

OBJECTIVE: Patients diagnosed with Lennox Gastaut syndrome (LGS), an epileptic encephalopathy characterized by usually drug resistant generalized and focal seizures, are often considered as candidates for vagus nerve stimulation (VNS). Recent research shows that heart rate variability (HRV) differs in epilepsy patients and is related to VNS treatment response. This study investigated pre-ictal HRV in generalized onset seizures of patients with LGS in correlation with their VNS response. METHODS: In drug resistant epilepsy (DRE) patients diagnosed with LGS video-electroencephalography recording was performed during their pre-surgical evaluation. Six HRV parameters (time and-, frequency domain, non-linear parameters) were evaluated for every seizure in epochs of 10 min at baseline (60 to 50 min before seizure onset) and pre-ictally (10 min prior to seizure onset). The results were correlated to VNS response after one year of VNS therapy. RESULTS: Seven patients and 31 seizures were included, two patients were classified as VNS responders (≥ 50 % seizure reduction). No difference in pre-ictal HRV parameters between VNS responders and VNS non-responders could be found, but high frequency (HF) power, reflecting the parasympathetic tone increased significantly in the pre-ictal epoch in both VNS responders and VNS non-responders (p = 0.017, p = 0.004). SIGNIFICANCE: In this pilot data pre-ictal HRV did not differ in VNS responders compared to VNS non-responders, but showed a significant increase in HF power - a parasympathetic overdrive - in both VNS responders and VNS non-responders. This sudden autonomic imbalance might have an influence on the cardiovascular system in the ictal period. Generalized tonic-clonic seizures are regarded as the main risk factor for SUDEP and severe seizure-induced autonomic imbalance may play a role in the pathophysiological pathway.

[Tentative results after implantation of isoelastic cementless hip-joint socket]. / Vorläufige Ergebnisse nach Implantation isoelastischer zementfreier Hüftpfannen.

During the 3 years from 1979-1981 in 3 Austrian Accident Departments, 196 isoelastic acetabular components for total hip replacements were implanted. 3 different models were used as components of the femoral head. 194 acetabula were implanted without cement. In two cases cement had to be used because of extreme porosity or protrusion. Follow-up examination of 178 patients after 14-48 months yielded a good clinical result in 161 cases. 16 patients reported occasional pain, 38 patients had a slightly positive and 16 a definitely positive Trendelenburg's sign. On X-ray film 48 patients showed no change in bone structure at the borderline between bone and implant. Sclerosis and increased density of the surrounding bone were observed more frequently than formation of radiolucent seams or cysts. No definite signs of loosening were seen.