Real-time display of the stomach slow wave and its parameters in a newly designed electrogastrographic system

We designed a new three-channel electrogastrographic (EGG) system, which was easily operated on the Windows 95 platform and could automatically provide slow wave parameters. The purpose of the present study was to test its reliability and accuracy in clinical recording. The system included a signal acquisition device assembled on a printed circuit board. Recorded myoelectrical signals were filtered, amplified, digitized, and transmitted via this device into a notebook personal computer (PC). Based on the short-term Fourier transform the software could transfer the time domain of the signal into the frequency domain. Real-time displayed slow wave parameters, including dominant frequency/power, percent of normal frequency (2–4 cpm), instability coefficient in frequency/power, and power ratio, were automatically renewed every 64 s. Twenty healthy subjects (M/F, 12/8; age, 23–51 years) were enrolled to measure both fast and postprandial myoelectrical activities for each 30-min recording. Our results indicated that meal ingestion significantly increased dominant frequency (3.15 ± 0.20 vs 3.23 ± 0.23 cpm; P < 0.05) and power (26.1 ± 3.8 vs 28.4 ± 3.9 dB; P < 0.05). The power ratio of the meal effect was 2.02 ± 2.07. Other parameters, including instability coefficient and percent of normal frequency, remained similar despite food ingestion. This newly designed EGG system is acceptable for clinically measuring gastric myoelectrical activity; the real-time display of many EGG parameters is an advantage with this new system. Received: May 1, 2000 / Accepted: July 28, 2000     

Electrogastrography in Patients with Chagas' Disease

Electrogastrograghy (EGG) was performed in 33 patients with Chagas' disease and in 15 healthy volunteers—control group. The EGG was performed in two different periods: in fasting and postprandial. The EGG was submitted to a continuous spectral analysis. The following parameters were evaluated: % dominant frequency in spectral bands: normogastria (2–4 cpm), bradygastria (1–2 cpm), tachygastria (4–10 cpm) and duod/resp (10–15 cpm). EGG was considered normal if normogastria > 65% in both EGG periods. The chagasic group showed % normogastria significantly lower (basal, P < 0.01), % bradygastria (basal, P = 0.01) and % tachygastria (basal and postprandial, P =.001) significantly higher than the control group. EGG was normal in 14/15 (93%) in control group × 16/33 (53%) in chagasic group (P < 0.05). It was concluded that: 1) the prevalence of gastric dysrhythmias was higher in chagasic patients than in comparison to a control group 2) gastric dysrhythmias may be considered one of the abnormalities presented in the chagasic gastropathy.     

Electrogastrography in healthy subjects

Electrogastrography (EGG) permits measurements of the gastric electrical activity. However, normal values of electrical activity are poorly defined. In addition, limited data are available on the effect of age and gender. Therefore, in 40 healthy subjects (age range: 19–90 years) normal values for several EGG parameters were assessed after an overnight fast for 1 hr in the fasting and fed state after ingestion of a standardized solid-liquid meal. The electrical signals were capture by a pair of surface electrodes sonographically placed on the skin overlying the gastric antrum. The dominant electrical frequency was predominantly in the defined normal frequency range between 2 and 4 cycles per minute (cpm) (P<0.001) and was higher in the postprandial than in the preprandial period (3.1 cpm vs 2.8 cpm,P=0.02). The instability of the electrical rhythm calculated by a dominant frequency instability coefficient (DFIC) was postprandially lower than in the fasting state (P=0.04). The electrical power (amplitude) increased postprandially (postprandial to fasting power ratio =2.4). To evaluate the influence of age and gender on normal values the subjects were divided into four groups (median age: male, 28 and 69 years; female, 25 and 67 years). The most parameters did not differ significantly between the groups. However, DFIC was different between the groups (P<0.05), with elderly women revealing lowest DFIC. In conclusion, normal values for several EGG parameters evaluated in this study should be included in the analysis of gastric electrical activity. The magnitude of electrical frequency and power are not influenced by age and gender, whereas the instability of the electrical frequency is influenced by these factors.     

Electrogastrographic characteristics in patients of stomach cancer

Using a homemade electrogastrography (EGG) system, we studied the characteristics of myoelectrical rhythm in gastric cancer (GC) patients. Based on a short-term Fourier transform, recorded slow waves could be automatically analyzed to obtain the following parameters: dominant frequency/power, percent of normal rhythm (2.4–3.7 cpm), power ratio, etc. Fifty histologically confirmed GC patients (34 men, 16 women) were enrolled before surgical intervention to measure their fasting and postprandial EGG parameters for 30 min. The cancerous parameters of GC patients were then obtained postoperatively. In addition, 46 healthy subjects were enrolled for comparison. When compared to controls, GC patients had the following characteristics: absence of postprandial increase in dominant frequency (GC: 3.04 ± 0.47 vs 3.07 ± 0.44 cpm, NS; controls: 3.02 ± 0.31 vs 3.21 ± 0.25 cpm, P < 0.001), marked power response after meal (P < 0.05), and obvious power ratio (4.58 ± 7.38 vs 2.27 ± 2.05, P < 0.05). Multivariate analysis indicated that advanced GC was the factor responsible for the obvious dominant power enhancement after meal (P < 0.05). Other demographic, clinical, and cancerous factors did not influence EGG parameters. We conclude that apparent arrhythmia is not encountered in GC patients, although they mainly exhibit obvious postprandial power response. Advanced GC is likely responsible for this power enhancement on EGG recording.     

Evaluation of Residual Stomach Motility After Proximal Gastrectomy for Gastric Cancer by Electrogastrography

The relationship between the motility and the size of the residual stomach after proximal gastrectomy was evaluated using electrogastrography (EGG). Based on fast Fourier transformation, recorded slow waves could be analyzed to obtain the following parameters: dominant frequency (DF), percentage normal frequency (% 3 cycles per minute [cpm]), and power ratio (PR). EGG parameters, the length of the greater curvature of the residual stomach (LGC), were recorded in 18 gastrectomized patients. Compared to 12 healthy controls, the gastrectomized patients had abdominal EGG parameters including lower %3cpm (43 ± 21% vs 83 ± 7%; P < 0.05), DF (2.2 ± 0.4 vs 3.0 ± 0.2 cpm; P < 0.05), and PR (1.5 ± 0.8 vs 2.5± 0.8; P < 0.05). In relation to LGC and parameters, there was no difference between the patients whose LGC was > 20 cm and controls in PR (2.3± 0.9 vs 2.5± 0.8; n.s.). In conclusion, the motility of the residual stomach would be equal to that of the nonresected stomach as if the volume of the residual stomach was more than half.     

Gastric Dysrhythmias and Delayed Gastric Emptying in Patients with Functional Dyspepsia

An association between dyspepsia, gastricmotility disorders, and myoelectrical abnormalities hasbeen noted. The objective of the present study was toinvestigate both antral myoelectrical activity and gastric emptying in patients with functionaldyspepsia (FD). Electrogastrography (EGG) was performedin 25 adult patients with FD, which had been evaluatedby score. After an overnight fast, for 1 hr in the pre- and postprandial state (370 kcalliquid-solid test meal) the following EGG parameterswere determined: dominant frequency [DF (cpm)], DF (%)in the normal range (2-4 cpm), bradygastria (<2 cpm), tachygastria (4-10 cpm), dominant frequencyinstability coefficient (DFIC), and postprandial tofasting power ratio (PR). The data were correlated toresults obtained in 20 age- and gender-matched controls. In addition, in 17 consecutive patients the EGGdata were compared to the gastric retention ofradionuclides after 60 min (liquid-solid phase labeledwith ^99mTc colloid). Patients with FDrevealed a preprandial increase in tachygastria compared to controls(P < 0.001). Of 17 FD, seven patients exhibiteddelayed gastric emptying (t60 retention >68%). Thesepatients showed significantly more pre- and postprandial tachygastrias than patients with normal gastricemptying (P < 0.05). The dyspeptic symptology and H.pylori status did not correlate with EGG andradioscintigraphy. Patients with FD frequently revealimpaired gastric emptying and increased tachygastria,which may have pathophysiological significance in someof these patients.     

An Evaluation of Adult Electrogastrography Criteria in Healthy Children

The current study examined whether electrogastrogram (EGG) recordings obtained from healthy children would be considered normal by standards established for adults and whether EGG patterns differ between children/adolescents and adults. Twenty-eight healthy children (54% females; ages 8–17 years; mean = 12.4 years) were evaluated and compared to 15 healthy adults evaluated previously. EGGs were recorded for 30 min in the fasting state and for 1 hr following a standard meal. For both pediatric and adult participants, there was a significant increase in both the dominant frequency and the dominant power from the pre- to the postprandial period (P < 0.001 for each). Using adult standards, the percentage normal slow waves was ≥70% of the recording time in 96% of children in the fasting state and in 100% in the postprandial period. A postprandial power increase was seen in 89% of the children. In conclusion, our data indicate that American Motility Society (AMS) consensus adult criteria for a normal EGG are appropriate to apply to children and adolescents when utilizing methodology and meal challenge similar to those used to establish the adult norms.     

Gastric myoelectrical activity in patients with type I diabetes mellitus and autonomic neuropathy

In patients with diabetes mellitus and gastroparesis, dysrhythmias of gastric myoelectrical activity, especially tachygastrias, are thought to be involved in the pathogenesis of dyspeptic symptoms. Using surface electrogastrography we studied the prevalence of these abnormalities, and their relationships to dyspeptic symptoms and the extent of cardiac autonomic neuropathy in 30 euglycemic patients with type I diabetes mellitus and 12 controls. Neither in the fasting nor in the postprandial state were differences in mean frequency of gastric electrical control activity and its variability found between patients and controls. In the fasting state, the power content of the 3 cpm component in the power spectrum of the electrogastrogram was even higher in patients than in controls (P=0.049). In the fasting state, second harmonics of the 3 cpm fundamental gastric signal were seen more often in patients than in controls (P=0.03). In patients with symptoms during the study, no second harmonics were found after the meal. The postprandial/fasting power ratio was decreased in patients with symptoms during the study as compared to patients without symptoms and controls (P<0.05). The incidence of dysrhythmias, such as tachygastrias and bradygastrias, was not higher in patients than in controls (17% and 8%, respectively). No correlation was found between electrogastrographic parameters and the severity of autonomic neuropathy or dyspeptic symptoms scored before the study. In conclusion, this study has shown that patients with type I diabetes mellitus and autonomic neuropathy studied under euglycemic conditions do not have grossly disturbed myoelectrical activity, except when symptomatic during the study.Supported by the Dutch Diabetic Foundation.     

Effect of hypo- and hyperthyroidism on gastric myoelectrical activity

Although hypo- and hyperthyroid patients have different symptoms in the gastrointestinal tract, the mechanism of thyroid action on the gut remains poorly understood. Thus the aim of this study was to investigate the effect of hypo- and hyperthyroidism on gastric myoelectrical activity, gastric emptying, dyspeptic symptoms. Twenty-two hyperthyroid (median age 45, 15 females) and 11 hypothyroid (median age 42, 10 females) patients were included into the study. Dyspepsia score, hypo- and hyperthyroid symptom scale, abdominal ultrasonography and upper gastrointestinal endoscopy were performed. Gastric myoelectrical activity was measured by electrogastrograpy (EGG) before and after therapy both preprandially and postprandially and compared with age, gender, and body-matched controls (12 for hypothyroid, 15 for hyperthyroid patients). Radionuclide gastric emptying studies were performed with a solid meal. Hypothyroid patients revealed a significant increase in preprandial tachygastria as compared with controls (12.3% vs 4.8%). The percentage of preprandial normal slow waves (2.4–3.7 cpm) was below 70% (dysmotility) in 7 of 11 hypothyroid patients versus 2 of 12 controls (P < 0.05). Hyperthyroid patients revealed a significantly higher preprandial (3.1 vs 2.8) and postprandial (3.4 vs 3) DF when compared with the controls (P < 0.05). A higher percentage of postprandial taschygastria (7.9 vs 0) was present in hyperthyroid patients than in the controls (P < 0.05). The decrease on postprandial EGG power (power ratio < 1) was observed in 7 patients the in hyperthyroid group and 1 in controls (P < 0.05). The percentage of postprandial normal slow waves was below 70% in 10 of 20 hyperthyroid patients vs 1 of 15 controls (P < 0.05). After therapy these differences disappeared in the euthyroid state. The hypo- and hyperthyroid symptom scale correlated to dyspepsia score. Dyspepsia score in hyperthyroidism correlated to power ratios in hyperthyroid patients. We detected some correlations between serum levels of fT3 or fT4 and some EGG parameters in hypo- and hyperthyroidism. Dyspepsia score and hypo- and hyperthyroid symptom scale were improved significantly after therapy in the euthyroid state. In conclusions, we showed gastric dysrhythmia by EGG in both hypo- and hyperthyroid patients. Dyspeptic symptoms correlated to the activity of thyroid disease. After therapy, these findings and dyspeptic symptoms improved in the euthyroid state. Abnormalities of power ratios may be responsible of dyspeptic symptoms in hyperthyroid patients. EGG may be a useful and noninvasive tool for detecting gastric disturbances during hypo- and hyperthyroidism.     

Electrogastrography prior to and following total gastrectomy,subtotal gastrectomy,and gastric tube formation

On electrogastrography (EGG) spectral analysis, an activity of 3 cycles per minute (cpm) is supposed to be specific for the stomach. After total or subtotal gastrectomy, the original site of the stomach is occupied mainly by the intestine. We attempted to determine if intestinal activity could be recorded in this region with EGG. Epigastric recordings were performed in patients prior and following gastrointestinal or control surgeries. Spectral analysis, using the maximal entropy method and ensemble means was applied to data analysis from these recordings. Preoperatively, the majority of the power peaks were found around 3, 6, and 11 cpm. The postprandial-to-fasting power ratio of all of these power peaks increased significantly postprandially (P<0.05–0.01). Following total gastrectomy, the power peak around 3 cpm disappeared or was significantly diminished in amplitude (P<0.05). The postoperative-to-preoperative power ratio ranged from 0.03 to 0.10 (P<0.001–0.01). However, the power peak around 11 cpm did not significantly change prior to or following total gastrectomy, and the 11 cpm peak appeared relatively dominant. Simultaneous manometric studies in the Roux limb demonstrated a correlation between the power spectral frequency of EGG and manometry at 11 cpm. Therefore, the 11 cpm peak appeared to reflect jejunal or Roux limb electrical activity. The postoperative to preoperative power ratio for the 3 cpm also was significantly reduced following subtotal gastrectomy and gastric tube formation in patients in the postprandial state (P<0.05–0.001).     

Inhibitory effects of cholecystokinin on postprandial gastric myoelectrical activity

While a number of studies have investigated the effects of cholecystokinin (CCK) on gastrointestinal motility, little is known on the effects of CCK on gastric myoelectrical activity, which regulates gastric motility. The aim of this study was to investigate the effects of intravenous infusion of CCK-8 on gastric myoelectrical activity in normal humans. Gastric myoelectrical activity was measured in 10 healthy subjects with a noninvasive electrogastrographic technique by placing abdominal electrodes on the epigastric area. Two study sessions were performed in each subject on two separate days with double-blinded infusion of either saline or CCK (24 pmol/kg/hr). The procedure for each session was as follows: (A) 30-min baseline fasting electrogastrogram (EGG); (B) start infusion, another 30-min EGG; (C) give meal, 60-min EGG; and (D) stop infusion, another 60-min EGG. The dominant frequency and peak power (amplitude) of the EGG, and the percentage of normal 2–4 cycles/min slow waves during each recording session were computed and compared between placebo and CCK. It was found that normal 3 cpm slow waves were recorded in all EGGs. Infusion of CCK had no effect on the frequency of the gastric slow wave and did not induce gastric dysrhythmias. It was also found that intravenous infusion of CCK significantly decreased the EGG peak power (amplitude) during the first hour after the meal (the infusion was given during this period) in comparison with placebo (P<0.05). This inhibitory effect on EGG peak power was sustained but not significant during the second postprandial hour (the infusion was not given during this period). It was concluded that intravenous infusion of CCK at a physiological concentration significantly decreased the postprandial EGG amplitude in normal humans, suggesting an inhibitory effect on postprandial gastric motility, but did not change the frequency and regularity of the gastric slow wave.     

Multichannel electrogastrography (EGG) in symptomatic patients: a single center study

OBJECTIVES: To determine the value of multichannel versus conventional single-channel electrogastrography (EGG) and of an additional postprandial hour recording in symptomatic patients. METHODS: Eighteen normal subjects and 47 patients with upper GI symptoms underwent multichannel EGG with four cutaneous recording electrodes placed on the antral axis. Fasting EGG was recorded for 1 h, followed by meal ingestion, followed by two 1-h postprandial EGG recordings. Variables assessed: (1) dominant frequency (DF) and its power; (2) percent time in normal (2-4) cpm frequency; (3) average percent of slow wave coupling (% SWC). RESULTS: Normal values for single-channel EGG were: (1) DF from 2.5-3.3, 2.7-3.5, and 2.6-3.5 cpm in the fasting, first, and second postprandial hours; (2) percentage of time in 2-4 cpm: >50%, >65%, and >65% in the fasting, first, and second postprandial hours. Normal values for percent SWC using multichannel EGG were >50%, >55%, >55% in the fasting, first, and second postprandial hours. In the symptomatic patients, an abnormal 2-h single-channel EGG was obtained in 16 of 47 (34%) patients. Adding an additional 1 h of postprandial recording identified another 4 abnormal patients (20/47 = 43%). With multichannel EGG, abnormal results were obtained in 24 of 47 patients (51%) with the 2-h study. An additional 1 h of postprandial recording identified another 4 patients as abnormal (28/47 = 60%). CONCLUSIONS: Multichannel EGG recording improved the detection of abnormal gastric myoelectric activity in symptomatic patients. This study also demonstrates prolonging the postprandial recording to 2 h increases the diagnostic yield for both single-channel and multichannel EGG.     

Effect of Meal Size and Test Duration on Gastric Emptying and Gastric Myoelectrical Activity as Determined with Simultaneous [13C]Octanoate Breath Test and Electrogastrography in Normal Subjects Using a Muffin Meal

Our purpose was to determine the effect of meal size on gastric emptying (GE) as measured by octanoate breath test (OBT), to determine the effect of the duration of breath collections on assessment of GE by OBT, and to determine the effect of meal size on gastric myoelectrical activity as measured by electrogastrography (EGG). Fourteen normal subjects underwent two modified [¹³C]OBTs using muffin meals of 250 or 350 kcal mixed with 100 mg [¹³C]sodium octanoate. T _1/2 for GE was determined for both the entire postprandial 6-hr breath collection and a truncated initial 4-hr data set. EGG was recorded for 30 min prior to the muffin meal and 4 hr postprandially. Using the 6-hr breath collection data, the T _1/2 was 177 ± 7 (mean ± sem) for the 350-kcal meal compared to 153 ± 7 min (P < 0.01) for the 250-kcal meal. Using the 4-hr data, the T _1/2 for the 350-kcal meal was 244 ± 32 min compared to 165 ± 12 min (P < 0.05) for the 250-kcal meal. The ratio of postprandial to fasting EGG power of the dominant frequency for the 350-kcal meal (1.9 ± 0.4) was higher than that for the 250-kcal meal (1.3 ± 0.6). T _1/2 for the 350-kcal meal using 4- and 6-hr data was significantly correlated with the 4-hr power ratio (r = 0.68 and 0.67; P < 0.05, respectively), but poorly correlated for the 250-kcal meal. In conclusions, GE and EGG are affected by meal size. Using the muffin-based [¹³C]OBT, T _1/2 for the 350-kcal meal was significantly longer than for a 250-kcal meal. Longer T _1/2 values were obtained with shorter breath sampling durations. The postprandial to fasting power ratio for the 350-kcal meal was greater than that for the 250-kcal meal.     

Antral Myoelectric Activity,Gastric Emptying,and Dyspeptic Symptoms in Diabetics

Background: Electrogastrography (EGG) enables the cutaneous measurement of gastric electric activity. An association between electric abnormalities and gastrointestinal motility disorders has been shown. The primary objective of this study was to investigate whether diabetic gastroparesis could be predicted by EGG.

Methods: EGG was performed in 18 insulin-treated type-II diabetics (9 female, 9 male; median age, 64 years; range, 45-76 years) with chronic dyspepsia. After an overnight fast, during 1 h in the fasting and 1 h in the fed state after ingestion of a liquid-solid test meal (370 kcal; liquid phase labeled with 0.5 mCi ^99mTc-colloid) antral electric activity was captured by one pair of electrodes sonographically placed on the skin overlying the gastric antrum. Several EGG variables including dominant frequency (DF), percentages of DF in the normal range (24 cycles per minute (cpm)), bradygastria (<2cpm), and tachygastria (4-10 cpm), dominant frequency instability coefficient (DFIC), and postprandial to preprandial power ratio (PR) were calculated by fast Fourier transform. The data were correlated to results obtained in 20 age- and gender-matched healthy subjects (10 female, 10 male; median age, 68 years; range, 53-90 years). In addition, the data were compared with the percentages of retention of the radionuclide in the stomach at 60 min, and lag times measured by simultaneous scintigraphy.

Results: The EGG values obtained in diabetics did not differ significantly from those in healthy subjects and did not correlate with radioscintigraphy (p > 0.05). Moreover, the EGG values in diabetics with delayed gastric emptying (about 40%) did not differ from data in diabetics without gastroparesis. Furthermore, whereas dyspepsia correlated significantly with radioscintigraphy, no correlation with EGG could be found.

Conclusions: Electrogastrography seems to be unsuitable for assessment of motility disorders in type4 diabetics.     

Impaired Postprandial Gastric Myoelectrical Activity in Chinese Patients with Nonulcer Dyspepsia

Using a homemade electrogastrography (EGG) system, we studied the characteristics of the myoelectrical rhythm in Chinese patients with nonulcer dyspepsia (NUD). Based on short-term Fourier transformation, recorded slow waves could be automatically analyzed to obtain the following parameters: dominant frequency/power, percent of normal frequency (2–4 cpm), power ratio, etc. EGG parameters, Helicobacter pylori status, histological examination of gastric mucosa, and dyspeptic symptoms were recorded in 27 NUD patients. Compared to 32 healthy controls, the Chinese NUD patients had abnormal postprandial EGG parameters including a lower percentage of regular 2–4 cpm slow waves (70.10 ± 2.97% vs 79.08 ± 2.95%, P < 0.05), a lower level of increment of dominant power (0.62, ± 0.91 vs 3.76 ± 0.58 dB, P < 0.05), lower power ratio (1.42 ± 0.28 vs 2.79 ± 0.39, P < 0.05) and a higher instability coefficient (0.36 ± 0.03 vs 0.26 ± 0.03, P < 0.05). However, Helicobacter pylori infection and its associated gastritis did not influence any EGG parameters in NUD patients. Six main dyspeptic symptoms and total symptom score had no correlation with any EGG parameters. In conclusion, Chinese NUD patients may have abnormal postprandial stomach myoelectrical activity, but these EGG abnormalities are not a direct result of Helicobacter pylori infection and its related gastritis and do not contribution to the dyspeptic symptoms.     

Abnormal gastric myoelectrical activity and delayed gastric emptying in patients with symptoms suggestive of gastroparesis

Gastric myoelectrical activity modulates gastric motor activity. Abnormalities in gastric myoelectrical activity may be associated with gastric motility disorders. The aim of this study was to investigate the correlation of gastric myoelectrical activity with gastric emptying in symptomatic patients with and without gastroparesis. Ninety-seven patients with symptoms suggestive of gastroparesis participated in the study. Gastric myoelectrical activity was recorded using surface electrogastrography. The electrogastrogram (EGG) was recorded for 30 min in the fasting state and for 120 min after a solid test meal. Gastric emptying of the solid meal was simultaneously monitored for 120 min. Patients with delayed gastric emptying showed a significantly lower percentage of normal gastric slow waves (P<0.03) and a significantly reduced increase of the dominant power in the postprandial EGG (P<0.02). Postprandial EGG parameters were found to be able to predict delayed emptying of the stomach. Postprandial gastric dysrhythmia predicts delayed gastric emptying with an accuracy of 78%, while the abnormality in postprandial EGG power predicts delayed gastric emptying with an accuracy of 75%. All patients with abnormalities in both the rhythmicity and the power had delayed gastric emptying. Patients with delayed gastric emptying have a lower percentage of normal gastric slow waves in the EGG and a lower postprandial increase in the dominant power. Abnormalities in the postprandial EGG seem to be able to predict delayed emptying of the stomach. However, a normal EGG does not seem to guarantee normal emptying of the stomach.     

Gastric myoelectrical activity and gastric emptying in patients with functional dyspepsia

OBJECTIVES: The aims of this study were to investigate gastric myoelectrical activity and gastric emptying (GE) and their relationship in patients with functional dyspepsia. METHODS: The study was conducted in 15 healthy volunteers (six women, nine men, mean age: 42 yr) and 15 patients (13 women, two men, mean age: 43 yr) with functional dyspepsia. Gastric myoelectrical activity was recorded using cutaneous electrogastrography (EGG) for 30 min in the fasting state and for 120 min simultaneously with GE monitoring after an isotope-labeled solid meal. The anterior/posterior images of the stomach were taken using a technetium scanner immediately after eating, and then at 1, 2, and 4 h to determine the percentage of gastric retention. The dominant frequency of the EGG, the change of the postprandial EGG peak power (deltaP), and the percentage of normal 2-4 cycles/min (cpm) slow waves during each recording session were calculated and compared between the patients and healthy subjects. RESULTS: The patients had a significantly lower mean percentage of 2-4 cpm slow waves, both in the fed state and in the fasting state, than did healthy subjects. Compared to the EGG in the fasting state, a significant increase of the EGG dominant frequency in the fed state was observed in healthy subjects but not in the patients. The mean postprandial EGG power increase in the patients was substantially less than in the healthy subjects during the first postprandial hour but similar during the second postprandial hour. The mean percentage of gastric retention in patients is substantially higher than in the healthy subjects, both at 2 h after eating and at 4 h after eating. Of 15 patients, nine (60%) had delayed GE (gastric retention at 2 h >50%) and 10 (66%) had abnormal EGGs (percentage of 2-4 cpm <70% and/or deltaP < 0). Eight of these 10 patients (80%) with abnormal EGGs had delayed GE. CONCLUSIONS: A high proportion of adult patients (60%) with functional dyspepsia have abnormally slow GE and abnormalities in gastric myoelectrical activity.     

Electrogastrography Before and After a High-Caloric,Liquid Test Meal in Healthy Volunteers and Patients with Severe Functional Dyspepsia

Background: The cutaneous recording of gastric electric rhythm, so-called electrogastrography (EGG), has been purported as a non-invasive method for studying patients with functional dyspepsia and unexplained nausea and vomiting. The aims of this study were to determine normal values for EGG characteristics before and after a liquid, high-caloric test meal and to investigate whether EGG could discriminate between patients with functional dyspepsia and normal controls. Methods: In studying 20 healthy volunteers and 10 patients with functional dyspepsia, we recorded gastric electrical activity during the 30 min before and after a liquid 1.0-1.5 kcal/ml test meal. Satiety before and after the meal was estimated on a 10-point scale. EGG was analysed regarding dominant frequency, instability of the dominant frequency, power ratio and percentage activity in the normal frequency range. Results: The mean ( ± s ) caloric intake in patients with functional dyspepsia (286 ± 160 kcal) was significantly lower ( P < 0.001) than in healthy volunteers (610 ± 211 kcal). The patients reported a more pronounced feeling of satiety before the test meal (5.6 ± 3.2) compared to healthy volunteers (3.6 ± 1.2, P < 0.05), but at the end of the test meal there was no difference in satiety (7.9 ± 2.5 versus 7.7 ± 1.0). However, none of the EGG parameters showed any difference between patients and healthy volunteers. Conclusions: EGG before and after a high-caloric test meal showed large variation in healthy subjects and seemed to be of little value for differentiating between healthy individuals and patients with functional dyspepsia.     

Identification of Gastric Contractions from Cutaneous Electrogastrogram

Objective : The objective of this study was to investigate whether gastric contractions in the fasting and fed state can be identifled from the cutaneous electrogastro-gram. Methods : Simultaneous measurements of gastric myoelectrical and manometric activities were made in 10 healthy female volunteers from 1:00 AM to 9:45 AM. For manometric recording, a catheter incorporating solid state transducers was used. Cutaneous electro-gastrography (EGG) was used for myoelectrical recording. All EGG data from 1:00 AM to 7:30 AM that occurred during motor quiescence, all EGG data that occurred during antral contractions, and 2-h EGG data after breakfast given at 7:30 AM were quantitatively analyzed and compared with each other. The EGG in three specific periods (fasting without antral contractions, fasting with contractions, and postprandial) was characterized by four parameters that include frequency, power, and stabilities of the frequency and power. Results: 1 ) the peak power of the postprandial EGG was, respectively, 12.5 dB (about 2-fold increase n i amplitude) and 6.8 dB (ahout 1-fold increase in amplitude) higher than that during motor quiescence (p < 0.05) and motor activity in the fasting state; 2) the dominant frequency of the postprandial EGG was, respectively, 6% and 13% higher than that during motor quiescence and motor activity (p < 0.05) in the fasting state; 3) the peak power of the fasting EGG was 48% more unstable during motor activity than motor quiescence (p < 0.05); 4) the stability of the EGG frequency was not significantly different during the three different periods. Conclusion : The EGG provides important and useful information for the assessment of gastric motility. An unstable EGG peak power is indicative of gastric contractions in the fasting state. An increase in EGG peak power and/or dominant frequency after a solid test meal suggests a normal postprandial gastric motility.     

Glucagon-like peptide 1 abolishes the postprandial rise in triglyceride concentrations and lowers levels of non-esterified fatty acids in humans

Aims/hypothesis Diabetic dyslipidaemia contributes to the excess morbidity and mortality in patients with type 2 diabetes. Exogenous glucagon-like peptide 1 (GLP-1) lowers postprandial glycaemia predominantly by slowing gastric emptying. Therefore, the effects of GLP-1 on postprandial lipid levels and gastric emptying were assessed. Methods 14 healthy male volunteers were studied with an i.v. infusion of GLP-1 (1.2 pmol kg⁻¹ min⁻¹) or placebo over 390 min in the fasting state. A solid test meal was served and gastric emptying was determined using a ¹³C-labelled sodium octanoate breath test. Venous blood was drawn frequently for measurement of glucose, insulin, C-peptide, glucagon, GLP-1, triglycerides and NEFA. Results GLP-1 administration lowered fasting and postprandial glycaemia (p<0.0001). Gastric emptying was delayed by GLP-1 compared with placebo (p<0.0001). During GLP-1 administration, insulin secretory responses were higher in the fasting state but lower after meal ingestion. After meal ingestion, triglyceride plasma levels increased by 0.33±0.14 mmol/l in the placebo experiments (p<0.0001). In contrast, the postprandial increase in triglyceride levels was completely abolished by GLP-1 (change in triglycerides, −0.023±0.045 mmol/l; p<0.05). During GLP-1 infusion, plasma concentrations of NEFA were suppressed by 39% in the fasting state (p<0.01) and by 31±5% after meal ingestion (p<0.01). Conclusions/interpretation GLP-1 improves postprandial lipidaemia, presumably as a result of delayed gastric emptying and insulin-mediated inhibition of lipolysis. Thus, by lowering both glucose and lipid concentrations, GLP-1 administration may reduce the cardiovascular risk in patients with type 2 diabetes.