Cardiovascular regulation and hippocampal sclerosis.
OBJECTIVE
Cardiovascular dysregulation has been detected in patients with temporal lobe epilepsy (TLE) by using cardiovascular reflex tests and analysis of heart rate variability (HRV). The two methods have not previously been used in the same study to compare them in the assessment of cardioregulatory function. Magnetic resonance imaging (MRI) is considered the best method to reveal structural changes such as hippocampal sclerosis associated with TLE. It is not known whether these structural changes modify cardioregulatory function in patients with TLE.


METHODS
Standard cardiovascular reflex tests and analysis of spectral and dynamic measures from 24-h electrocardiogram (ECG) recordings were performed for eight patients with and 31 patients without hippocampal sclerosis and for 72 control subjects. MRI also was performed in each patient to reveal hippocampal sclerosis.


RESULTS
Various measures of cardiovascular reflexes and HRV were diminished in patients with TLE compared with the control subjects. No significant differences were found in the measures obtained from the cardiovascular reflex tests or analysis of HRV between those with and without hippocampal sclerosis, although a nonsignificant trend toward reduced values was seen among those with hippocampal sclerosis. The values of cardiovascular reflexes and spectral analysis of HRV correlated with each other.


CONCLUSIONS
These results suggest that functional rather than structural changes related to TLE are involved mainly as a mechanism of altered cardioregulatory function. The cardiovascular reflex test and analysis of HRV both appear to be useful in studying cardioregulation in patients with TLE.
Ansakorpi
Hanna
H
Department of Neurology, University of Oulu, Finland. Hanna.Ansakorpi@oulu.fi
Korpelainen
Juha T
JT
Tanskanen
Päivikki
P
Huikuri
Heikki V
HV
Koivula
Antero
A
Tolonen
Uolevi
U
Pyhtinen
Juhani
J
Myllylä
Vilho V
VV
Isojärvi
Jouko I T
JI
D000328:Adult; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000503:physiopathology; D001341:Autonomic Nervous System / Q000503:physiopathology*; D002319:Cardiovascular System / Q000503:physiopathology*; D002940:Circadian Rhythm / Q000502:physiology; D004569:Electroencephalography / Q000706:statistics & numerical data*; D004833:Epilepsy, Temporal Lobe / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D007839:Functional Laterality; D006334:Heart Function Tests; D006339:Heart Rate / Q000502:physiology; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008991:Monitoring, Physiologic / Q000706:statistics & numerical data; D012598:Sclerosis