Effects of esophageal stimulation in patients with functional disorders of the gastrointestinal tract.
We studied the effects of esophageal electrical stimulation on cortical-evoked potentials (EPs) and power spectrum of heart rate variability (PS/HRV) in patients with diabetes and non-cardiac chest pain (NCCP). We also recorded cognitive-evoked potentials (P300 EPs) in response to an odd-ball stimulation in patients with NCCP. Diabetic patients did not yield reproducible cortical EPs. Their power spectra of heart rate variability (PS/HRV) showed an increased vagal modulation during stimulation. In patients with NCCP the P300 EPs were of greater amplitude (17 +/- 3 microV vs. 12 +/- 1 microV in controls, p < 0.04), while peak latencies were slightly elongated in patients (382 +/- 22 ms vs. 354 +/- 12 ms in controls). The PS/HRV in these patients also showed an increased vagal modulation of the sinus node activity. Our results suggest the following: (1) in patients with diabetes, afferent pathways and processing of sensory signals are likely to be impaired; (2) an increased perception of esophageal stimulation reflects an exaggerated brainstem response and altered cortical processing of visceral sensation in patients with NCCP.
Kamath
M V
MV
Department of Medicine, McMaster University, Hamilton, Ontario, Canada.
May
A
A
Hollerbach
S
S
Fitzpatrick
D
D
Bulat
R
R
Bajwa
A
A
Tougas
G
G
Fallen
E L
EL
Shine
G
G
Upton
A R
AR
D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000502:physiology; D002637:Chest Pain / Q000503:physiopathology*; D002648:Child; D003929:Diabetic Neuropathies / Q000503:physiopathology*; D004558:Electric Stimulation; D004947:Esophagus / Q000502:physiology*; D018913:Event-Related Potentials, P300; D005073:Evoked Potentials, Somatosensory; D005767:Gastrointestinal Diseases / Q000503:physiopathology; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D010465:Perception / Q000502:physiology; D015203:Reproducibility of Results