Effect of Peritoneal Dialysis on Gastric Myoelectrical Activity in Patients with Chronic Renal Failure

Impaired gastric myoelectrical activity has been reported in patients with chronic renal failure (CRF). The effect of peritoneal dialysis on this function has not previously been described. The aim here was to investigate the effect of peritoneal dialysis on gastric myoelectrical activity. Gastric myoelectrical activity was recorded by electrogastrography (EGG) in 23 patients with CRF (18 with dyspepsia) during peritoneal dialysis and with the peritoneal cavity empty of dialysis fluid (14 patients), and in 20 healthy controls. Two 30-min EGG recordings before and after a solid test meal were analyzed using spectral analysis methods. No significant difference in the percentage of normal 2- to 4-cpm slow waves was found in patients on peritoneal dialysis compared to those with the peritoneal cavity empty of dialysis fluid or to controls (in fasting state 83 ± 3%, 80 ± 5% and 89 ± 4%, in fed state 91 ± 3%, 86 ± 4% and 83 ± 4%, respectively). It was found that the power ratio (change in power of normal slow waves in fed state) was significantly higher in the 14 patients on peritoneal dialysis compared to the same patients with the peritoneal cavity empty of dialysis fluid (27.2 ± 10.7 vs 8.6 ± 4.8, P < 0.05). There was no significant difference in the power ratio between patients with the peritoneal cavity empty of dialysis fluid and controls (8.6 ± 4.8 vs 7.5 ± 2.2). The subgroup of patients with no dyspepsia had a significantly higher power ratio compared to those with dyspepsia both on dialysis and with the peritoneal cavity empty of dialysis fluid (39.4 ± 13.7 vs 12.4 ± 5.2 and 29.2 ± 21.5 vs 2.8 ± 0.4 respectively, P < 0.05). In conclusion, there was no significant difference in gastric myoelectrical activity between patients with the peritoneal cavity empty of dialysis fluid and controls. Dialysis fluid in the peritoneal cavity seems to enforce the gastric myoelectrical signal.     

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.     

Impaired Gastric Myoelectrical Activity in Patients with Chronic Renal Failure

Dysmotility and delayed emptying of the stomachhave been reported in patients with chronic renalfailure (CRF). The aim of this study was to investigatewhether gastric myoelectrical activity was impaired in patients with CRF using electrogastrography.The electrogastrogram (EGG) was recorded in 24symptomatic patients with CRF (15 with diabetes) and 12normal subjects. Two 30-min EGG recordings before and after a test meal were analyzed using spectralanalysis methods. It was found that patients with CRFshowed a significantly lower percentage of normal 2-4cpm slow waves in both fasting and fed states in comparison with healthy controls (in fastingstate: 88.9 ± 2.5% vs 67.4 ± 6.6%/63.27.0%, P < 0.01; in fed state: 89.6 ± 1.8% vs64.6 ± 6.2%/62.0 ± 8.3%, P < 0.01;controls vs diabetic patients/nondiabetic patients). Both patient groups showed a significantlyhigher prevalence of the abnormal EGG, which was definedas the percentage of 2-4 cpm slow waves lower than 70%(fasting state: 8% vs 60%/56%, P < 0.01/0.05; fed state: 0% vs 53%/56%, P < 0.005/0.002;controls vs diabetic patients/nondiabetic patients). Nosignificant difference was observed in the regularity ofthe gastric slow waves between the two patient groups. The healthy controls showed a significantincrease in the dominant power and frequency of the EGGafter the test meal. However, this increase was absentin the two patient groups. It was concluded that patients with chronic renal failure haveabnormal gastric myoelectrical activity, includingimpaired regularity of the gastric slow wave and afailed increase in the power of the EGG at 3 cpm.Electrogastrography is an attractive noninvasive method for thestudy of gastric motility in patients with severechronic renal failure.     

Effects of Octreotide and Erythromycin on Gastric Myoelectrical and Motor Activities in Patients with Gastroparesis

Simultaneous recordings of gastric manometry andmyoelectrical activity were made in 10 patients withgastroparesis. Intravenous erythromycin (100 mg) wasadministered in the fasting state for a period of 30 min. Subcutaneous injection of octreotide(100 g) was administered before one of the fouridentical test meals. It was found that octreotidesignificantly decreased the antral motility index(30-min fasting: 4.51 ± 1.04 vs 1.75 ±0.97, P < 0.02; 60-min fed: 5.16 ± 1.44 vs 3.4± 1.41, P < 0.05) and the dominant power ofthe EGG (fasting power: 35.19 ± 1.54 vs 30.84± 1.57 dB, P < 0.004; postprandial powerincrease: 5.52 ± 1.06 vs 0.27 ± 0.87, P< 0.001). Erythromycin significantly increased theantral motility index (3.16 ± 0.96 vs 9.5± 0.61, P < 0.001) and the dominant power ofthe EGG (28.86 ± 1.57 dB vs 33.55 ± 1.59dB, P < 0.005) in the fasting state. An improvement in theregularity of the gastric slow wave was also noted witherythromycin. It was concluded that: (1) the inhibitoryeffect of octreotide on postprandial gastric motility and myoelectrical activity suggests thatcaution should be exercised when octreotide is used inpatients with gastroparesis; and (2) the stimulatoryeffect of erythromycin on gastric myoelectrical activity may enhance gastric motility and gastricemptying in patients with gastroparesis.     

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.     

Inhibitory reflexive effect of rectal distension on postprandial gastric myoelectrical activity

The aim of the study was to determine the effects of low-volume rectal distension on gastric myoelectrical activity. The study was performed in 14 healthy volunteers in 2 randomized sessions. In the control session, a small balloon was inserted into the rectum 10 cm beyond the anal verge and inflated with 20 ml of air. Gastric myoelectrical activity was recorded for 30 minutes in the fasting state and 30 minutes after a meal; and then the balloon was deflated and removed, and another 30-min recording was followed. The study session was the same except that after the 30-min baseline recording the balloon was inflated to reach a volume with which the subject felt an urgency for defecation. Spectral analyses were performed to compute the dominant frequency, power, and regularity (2–4 cycles/minutes, cpm) of the gastric slow waves and the percentage of gastric dysrhythmia. Results: 1). In comparison with our previously published data, the placement of the rectal balloon with a volume of 20 ml air did not affect the regularity of the slow waves (84.2 ± 3.6% in fasting, 85.3 ± 4.3% in fed); In comparison with the control session, the rectal distension inducing an urgency for defecation (average volume of air: 72.5 ml) significantly reduced the regularity of gastric slow waves in the fed state (72.0 ± 5.7%, P < 0.03 vs baseline; P < 0.02, vs control session) but not in the fasting state (80.1 ± 4.5%, P = 0.1). This postprandial change was attributed to a significant increase in bradygastria (3.1 ± 1.0% vs 7.9 ± 2.6%, P < 0.04) and a marginal increase in tachygastria (7.4 ± 2.5% vs 15.8 ± 4.3%, P = 0.06). The normal postprandial increases in the dominant frequency and power of the gastric slow wave were abolished in both sessions. conclusions, rectal distension evoking an urgency for defecation impairs postprandial gastric slow waves with an increase in the percentage of both bradygastria and tachygastria.     

Inhibitory effect of white wine on gastric myoelectrical activity and the role of vagal tone

Although extensively investigated throughout the gastrointestinal tract, the influence of alcohol on gastric motility is still unclear. Our aim was to investigate the effect of wine on gastric myoelectrical activity and vagal activity. Ten healthy subjects were studied in two sessions with the electrogastrogram (EGG) for 30 min at baseline, 30 min after ingesting the test liquid [white wine (12.5% alcohol) or matched juice], and 60 min after a standard test meal. Spectral analysis was performed to compute EGG parameters and their postprandial changes. The vagal activity was assessed based on spectral analysis of the heart rate variability (HRV) signal derived from the ECG recording. White wine preload significantly diminished the postprandial increase in EGG dominant power compared to juice preload (1.16 ± 1.57 vs 5.48 ± 1.01 dB, P < 0.001). A significant decrease in vagal activity was observed after wine (23.40 ± 4.30 vs 17.43 ± 3.40%, P < 0.005), which remained unchanged after the test meal (23.40 ± 4.30 vs 16.77 ± 4.40%, P < 0.05). This decrease was not noted in the juice session. A correlation was established between changes after wine consumption in EGG dominant power and in the percentage of the vagal activity (r = 0.89, P < 0.05). In conclusion, white wine preload inhibits the postprandial EGG dominant power, suggesting a possible inhibition of postprandial gastric contractions. This effect may be associated with diminished vagal activity.     

Impairment of Gastric and Jejunal Myoelectrical Activity During Rectal Distension in Dogs

It is known that distension of the rectum induces gastric hypomotility and delays gastric emptying. Its effect on gastrointestinal myoelectrical activity has not been well studied, however. The aim of this study was to investigate the effects of rectal distension on gastrointestinal myoelectrical activity in dogs. Six hound dogs implanted with electrodes on the serosa of the stomach and proximal jejunum were studied. The protocol consisted of a 30-min baseline recording and another 30-min recording during rectal distension. Gastric myoelectrical activity was severely impaired by rectal distension. The dominant power was significantly decreased from –2.79 ± 0.52 dB at baseline to –4.84 ± 1.26 dB during distension (P < 0.05). The percentage of normal 4–6 cycles per minute gastric slow waves was reduced from 95.08 ± 1.11% to 83.63 ± 4.00% (P < 0.02), and the percentage of tachygastria was increased during distension (0.33 ± 0.19% vs 6.03 ± 1.27%, P < 0.02). The instability coefficient of the dominant frequency was significantly increased (0.134 ± 0.012 vs 0.326 ± 0.074, P < 0.05). The percentage of slow wave coupling was reduced from 93.99 ± 0.76% to 73.43 ± 2.07% (P < 0.00003). In the small bowel, only the instability coefficient of dominant frequency showed a significant increase during distension. Other parameters were not affected by rectal distension. We conclude that rectal distension severely impairs gastric myoelectrical activity. The induced gastric dysrhythmia and reduced slow wave amplitude and coupling may be the underlying pathophysiology of gastric hypomotility and delayed gastric emptying observed during rectal distension.     

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.     

Impaired Postprandial Gastric Slow Waves in Patients with Functional Dyspepsia

The aim of this study was to investigate gastricmyoelectrical activity in patients with functionaldyspepsia. Thirteen healthy subjects and 14 patientswith functional dyspepsia participated in the study. The electrogastrogram (EGG) recording was madein each subject for 30 min in the fasting state and 120min after a standard test meal of 475 calories. Spectralanalysis methods were applied to derive quantitative EGG parameters. There was no difference in theEGG between the patients and controls in the fastingstate. However, abnormalities in the postprandial EGGwere found in the patients. The percentage of 2-4 cpmwaves was significantly lower (74.4 ± 4.0% vs85.7 ± 1.6%, P < 0.03) and the postprandialincrease in EGG dominant power was significantly less(–0.52 ± 0.92 dB vs 2.24 ± 0.88 dB,P < 0.03) in patients than in controls. It was alsofound that the percentage of postprandial 2-4 cpm wavescould be used to differentiate the patients withfunctional dyspepsia from the healthy controls with a specificity of 100% and a sensitivity of 43%. It was concluded that a subset of patients withfunctional dyspepsia have impaired gastric myoelectricalactivity in the fed state.     

Gastric Myoelectrical Activity in Patients with Parkinson's Disease (Evidence of a Primary Gastric Abnormality)

Parkinson's disease patients may experiencevarious gastrointestinal symptoms; however, the exactpathophysiology of these symptoms is not fullyunderstood. Therefore, the aim of this study was toinvestigate the pattern of gastric myoelectrical activityin patients with Parkinson's disease. Eleven patientswith Parkinson's disease and 10 healthy subjectsparticipated in the study. Patients were stratified as receiving dopaminergic therapy (N= 5) and off therapy (N = 6). Gastricmyoelectrical activity was measured by means of surfaceelectrogastrography (EGG) for 30 min before and for 90 min after a standardized meal. The dominantfrequency, postprandial EGG power change, and thepercentage of normal 2-4 cycles/min (cpm) slow-waveactivity in the three groups were calculated andcompared. The mean postprandial EGG power increase in theuntreated patients was smaller than in the treatedpatients (–3.11 ± 1.01 and 1.17 ±1.96 dB; P = 0.072). Moreover, both of these values weresignificantly decreased when compared to the control group(untreated vs control: d–3.11 ± 1.01 vs8.01 ± 1.86 dB; P = 0.04 and treated vs control:1.17 ± 1.96 vs 8.01 ± 1.86 dB; P = 0.02).The percentage of normal 2-4 cpm slow waves in untreated patients wasnot different from the treated patients (82.6 ±6.6% vs 75.8 ± 13.6%, P = NS) or from the controlgroup (88.2 ± 5.4%, P = NS). The dominantfrequency after the meal was similar to that in thefasting state both in the untreated (3.3 ± 0.1 vs3.2 ± 0.2 cpm; P = NS) and treated patients (3.2± 0.1 vs 3.1 ± 0.1 cpm, P = NS), whereasthe dominant frequency significantly increasedpostprandially in the control group (2.88 ± 0.12vs 3.05 ± 0.16; P < 0.05). Abnormalities ingastric myoelectrical activity in untreated Parkinson'sdisease patients reflect direct involvement of thegastrointestinal tract by the primary disease process.EGG can be regarded as a useful diagnostic tool inevaluating gastrointestinal involvement inneurodegenerative diseases.     

Clinical value of electrogastrography and the gastric emptying test

OBJECTIVE : To: (i) assess the clinical value of electrogastrography (EGG) and the gastric emptying test; and (ii) investigate the relationship between gastric myoelectrical activity and gastric emptying (GE). METHODS : One hundred and forty patients with functional dyspepsia (FD), 30 patients with non‐insulin‐dependent diabetes mellitus (NIDDM) and 20 healthy volunteers were studied. Gastric myoelectrical activity was recorded by using cutaneous EGG. The gastric emptying time was measured by using isotopic, radiopaque marker (Rom’s) and ultrasound methods. RESULTS : The dysrhythmia rates in patients with NIDDM were 70.0% (21/30) before meals and 66.7% (20/30) after meals, and the tachygastria rates of these patients were 36.7% before meals and 33.3% after meals. In NIDDM patients, the dominant frequency (DF) after meals (2.60 ± 0.30 cycles per minute; c.p.m.), the fed DF/fasting DF ratio (1.01 ± 0.11), the dominant power (DP) after meals (121.45 ± 67.00 V² c.p.m.) and the fed DP and fasting DP ratios (0.81 ± 0.07) were significantly lower than those in normal controls (P < 0.05 or P < 0.01). The DP after meals in patients with FD (210.60 ± 68.40 V² c.p.m.) was significantly lower than that in normal controls (P < 0.01). Delayed gastric emptying was more common in patients with FD and NIDDM. The rate of delayed gastric emptying in 121 cases with normal myoelectrical rhythm was 39.7% (48/121). In 69 cases with dysrhythmia, 45.9% (17/37) with bradygastria and 78.1% (25/32) with tachygastria had delayed gastric emptying. CONCLUSIONS : Electrogastrography and the gastric emptying test are feasible methods for evaluating gastric myoelectrical activity and gastric motility. The precise relationship between gastric myoelectrical activity and gastric motility has not been proven, but there is a close relationship between tachygastria and delayed gastric emptying.     

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.     

Characterization of Gastric Myoelectrical Rhythms in Patients with Systemic Sclerosis Using Multichannel Surface Electrogastrography

The aim of this study was to characterize multichannel surface electrogastrography (EGG) recordings in patients with systemic sclerosis (scleroderma, SSc) compared to normal controls. Ten SSc patients and 13 healthy age-matched controls were enrolled in this study. Gastric myoelectrical activity was recorded using a four-channel electrogastrograph with abdominal surface electrodes. The EGG was recorded in the morning for 1 hr in the fasting state, and 1 hr after a standardized (500 kcal) test meal. It was found that: (1) The regularity of the gastric slow wave was significantly lower in the SSc patients when compared with the normal controls in both fasting and fed states. (2) There was a significantly higher incidence of bradygastria in the SSc patients. (3) The SSc patients showed a significantly lower percentage of slow wave coupling among the four-channel EGGs than the controls. (4) In comparison with the controls, the patients showed an impaired spatial distribution of gastric slow wave power in both fasting and fed states and an impaired spatial distribution of slow wave frequency in the fasting state. It was concluded that SSc patients have an abnormal gastric slow wave as shown in the multichannel EGG as a decreased percentage of normal slow waves and impaired spatial coordination of gastric slow waves. The multichannel EGG may serve as a simple, noninvasive, and cost-effective method to assess gastric motility disorders and their relevance in patients with SSc.     

Alteration of gastric myoelectrical and autonomic activities with audio stimulation in healthy humans

Cold or emotional stress was reported to affect gastric myoelectrical activity. The aim of this study was to investigate the effects of music or noise on gastric myoelectrical activity and autonomic function in healthy volunteers.

Material and methods

The study was performed in 10 fasted healthy volunteers and included 30 min at baseline, 30 min of classical music via headphones and 30 min of loud household noises via headphones. The electrogastrogram (EGG) readings were recorded simultaneously with the electrocardiogram (ECG) recording.

Results

Both classical music and noise altered the regularity of gastric slow waves. The percentage of normal 2–4 cycles/min (cpm) waves was reduced from 77.9±4.7% at baseline to 66.9±5.4% during music (p<0.006) and 67.7±5.4% during noise (p<0.05). The reduction was attributed to a significant increase in bradygastria (15.8±3.9% versus 9.8±2.6%, p<0.04) with the music and a significant increase in arrhythmia (7.4±1.6% versus 2.0±1.1%, p<0.02) with the noise. The dominant frequency and power of the EGG were, however, not altered with either music or noise. Neither music nor noise had any effect on the autonomic function assessed by the heart rate variability.

Conclusions

Audio stimulation, with both music and noise, alters the rhythmicity of gastric slow waves. Classical music seems to increase bradygastria, whereas, household noise may increase arrhythmia. The effect of audio stimulation on the gastric slow wave does not seem to involve sympathetic or vagal efferent pathways assessed by the spectral analysis of heart rate variability.     

Duodenogastric bile reflux and gastrointestinal motility in pathogenesis of functional dyspepsia

To establish the pathogenic role of duodenogastric reflux in dyspeptic symptoms we have compared the clinical features, gastrointestinal motility, and rates of duodenogastric bile reflux in 12 cholecistectomized dyspeptic patients, 12 dyspeptic patients with intact gallbladder, and 12 healthy controls. Specific symptoms were scored for severity and frequency. Gastrointestinal manometry was performed during 3 hr of fasting and 2 hr postprandially. Simultaneously, samples of duodenal and gastric contents were obtained sequentially for quantification of bile acids. Results show that symptom global severity (9.6±0.4 vs 8.8±0.7) and frequency (9.9±0.8 vs 9.0±0.5) were similar in both dyspeptic groups; only abdominal pain was milder in cholecystectomized patients (1.9±0.1 vs 2.6±0.2;P<0.05). Fasting gastric bile acid concentrations were higher in cholecystectomized patients (P<0.05) and antral postcibal motility lower (P<0.05) than in the other groups. No relation among gastric hypomotility, duodenogastric bile reflux, and symptom scores was detected. We concluded that patients with functional dyspepsia and a prior cholecystectomy have clinical features similar to those with gallbladders, but some physiological features are dissimilar: antral motility is decreased and duodenogastric bile reflux is increased. Thus, a uniform clinical expression of various pathophysiological disturbances constitutes the basis of functional dyspepsia.     

Gallbladder function and gastric liquid emptying in achalasia

Because of evidence that the abnormalities in achalasia are not restricted to the distal esophagus, we investigated gallbladder function by cholescintigraphy in the steady state and in response to CCK and the scintigraphic gastric emptying of a liquid caloric meal in 10 individuals with achalasia and 10 normal controls. No abnormalities were found during the filling phase of the gallbladder but seven of the 10 patients showed a 50% reduction in the ejection fraction (39.4%±30.4 vs 80.3±8.3 of controls, mean±sd,P=0.007) and a slower than normal ejection phase (9.1%/min±6.6 vs 18.1±4.5,P=0.02. In eight of the 10 patients, gastric liquid emptying was accelerated with a T1/2 of 41.5 min±15.4 vs 74.7 min±11.5 in the controls (P=0.007). It is concluded that in some achalasia patients extraesophageal functional abnormalities of the gastrointestinal tract may be found. Whether these findings are promoted by degenerative changes of extraesophageal nerve fibers as well as their clinical significance require further investigations.This paper was presented as abstract at the American Gastroenterological Association Meeting, San Antonio, Texas, in May 1990.     

Gastric Myoelectrical Activity in Healthy Children and Children with Functional Dyspepsia

The aim of this study was to investigateabnormalities in pediatric patients with functionaldyspepsia. Fifteen symptomatic pediatric patientsdiagnosed with functional dyspepsia and 17 aged-matchedhealthy controls were studied. Gastric myoelectricalactivity was recorded using surface electrogastrographyfor 1 hr in the fasting state and 1 hr after a testmeal. It was found that, in comparison with thecontrols, the children with functional dyspepsia had alower percentage of 2- to 4-cpm slow waves in bothfasting state (66.0 ± 4.7% vs 79.7 ± 3.1%,P < 0.07) and fed state (72.4 ± 5.4% vs 85.0± 2.9%, P < 0.04), and a significantly higherinstability of the dominant frequency in both fastingstate (0.50 ± 0.05 vs 0.31 ± 0.04, P <0.01) and fed state (0.39 ± 0.05 vs 0.25 ±0.03, P < 0.05). It was also found the postprandial increase inEGG dominant power in the patients was inverselycorrelated with the total symptom score (r = 0.63, P =0.03). It was concluded that abnormal gastricmyoelectrical activity may play a role in the pathogenesis ofpediatric functional dyspepsia.     

Impaired gastric motility and its relationship to reflux symptoms in patients with nonerosive gastroesophageal reflux disease

Background  More than half of patients with refluxrelated symptoms have no endoscopic evidence of mucosal breaks. These patients are considered to have nonerosive gastroesophageal reflux disease (NERD). The pathogenesis of NERD may be multifactorial, but the role played by gastric motility in symptom generation in patients with NERD has not been examined. In this study, we elucidate gastric motility in patients with NERD and the efficacy of a prokinetic agent in the treatment of NERD. Methods  Gastric motility was evaluated with electrogastrography (EGG) and by measurement of gastric emptying using the acetaminophen method in 26 patients with NERD and in 11 matched healthy controls. NERD patients were treated with a prokinetic agent (mosapride 15 mg, orally three times daily) for a period of 4 weeks, after which gastric motility was measured again. Results  Compared with the healthy controls, the NERD patients showed a significantly lower percentage of normogastria, a lower power ratio in EGG, and delayed gastric emptying. Ten patients had normal gastric motor function (group A), and 16 showed abnormalities of either gastric myoelectrical activity or gastric emptying (group B). After treatment with mosapride, gastric motility improved significantly in both groups of patients compared with pretreatment values. The subjective assessment by the patient after the treatment was improved in 20.0% of group A versus 62.5% of group B patients (P < 0.05). Conclusions  Gastric hypomotility appears to be an important factor in reflux symptom generation in some NERD patients.