The Role of the Transdiaphragmatic Pressure Gradient (TGP) in the Pathophysiology of Proximal Reflux.

INTRODUCTION: An increased transdiaphragmatic pressure gradient (TGP) is a main element for distal gastroesophageal reflux disease (GERD). The role of TGP for proximal reflux is still unclear. This study aims to evaluate the presence, severity, and importance of proximal reflux in relationship to the TGP, comparing healthy volunteers, obese individuals, and patients with chronic obstructive pulmonary disease (COPD). METHODS: We studied 114 individuals comprising 19 healthy lean volunteers, 47 obese individuals (mean body mass index 45 ± 7 kg/m2), and 48 patients with COPD. All patients underwent high-resolution manometry and dual-channel esophageal pH monitoring. Esophageal motility, thoracic pressure (TP), abdominal pressure (AP), TGP, DeMeester score, and % of proximal acid exposure time (pAET) were recorded. RESULTS: Pathologic distal GERD was found in 0, 44, and 57% of the volunteers, obese, and COPD groups, respectively. pAET was similar among groups, only higher for obese individuals GERD + as compared to obese individuals GERD - and COPD GERD -. pAET did not correlate with any parameter in healthy individuals, but it correlated with AP in the obese, TP in the COPD individuals, and TGP and DeMeester score in both groups. When all individuals were analyzed as a total, pAET correlated with AP, TGP, and DeMeester score. DeMeester score was the only independent variable that correlated with pAET. CONCLUSIONS: Our results show that (a) TGP is an important mechanism associated with distal esophageal acid exposure and this fact is linked with proximal acid exposure and (b) obesity and COPD both seem to be primary causes for GERD but not directly for proximal reflux.

Does DeMeester score still define GERD?

Gastroesophageal reflux disease (GERD) clinical presentation may encompass a myriad of symptoms that may mimic other esophageal and extra-esophageal diseases. Thus, GERD diagnosis by symptoms only may be inaccurate. Upper digestive endoscopy and barium esophagram may also be misleading. pH monitoring must be added often for a definitive diagnosis. The DeMeester score (DMS) is a composite score of the acid exposure during a prolonged ambulatory pH monitoring that has been used since 1970s to categorize patients as GERD+ or GERD-. We showed in this review that DMS has some limitations and strengths. Although there is not a single instrument to precisely diagnose GERD in all of its variances, pH monitoring analyzed at the light of DMS is still a reliable method for scientific purposes as well as for clinical decision making. There are no data that show that acid exposure time is superior-or for that matter inferior-as compared to DMS.

High-resolution manometry findings in patients with achalasia and massive dilated megaesophagus.

Achalasia may present in a non-advanced or an advanced (end stage) stage based on the degree of esophageal dilatation. Manometric parameters and esophageal caliber may be prognostic for the outcome of treatment. The correlation between manometry and disease stage has not been yet fully studied. This study aims to describe high-resolution manometry findings in patients with achalasia and massive dilated megaesophagus. Eighteen patients (mean age 61 years, 55% females) with achalasia and massive dilated megaesophagus, as defined by a maximum esophageal dilatation >10 cm at the barium esophagram, were studied. Achalasia was considered secondary to Chagas' disease in 14 (78%) of the patients and idiopathic in the remaining. All patients underwent high-resolution manometry. Upper esophageal sphincter was hypotonic and had impaired relaxation in the majority of patients. Aperistalsis was seen in all patients with an equal distribution of Chicago type I and type II. No type III was noticed. Lower esophageal sphincter did not have a characteristic manometric pattern. In 50% of the cases, the manometry catheter was not able to reach the stomach. Our results did not show a manometric pattern in patients with achalasia and massive dilated esophagus.

Upper esophageal sphincter motility in gastroesophageal reflux disease in the light of the high-resolution manometry.

This study aims to evaluate the upper esophageal sphincter (UES) motility in patients with gastroesophageal reflux disease (GERD) as compared to healthy volunteers. We retrospectively studied the HRM tests of 44 patients (median age: 61 years, 54% females) under evaluation for GERD. The manometric UES parameters of these patients were compared to 40 healthy volunteers (median age: 27 years, 50% females). Almost half of the patients had a short and hypotonic UES. Patients with extraesophageal symptoms had a higher proportion of hypotonic UES as compared to patients with esophageal symptoms. Reflux pattern did not influence manometric parameters. Proximal reflux (any number of episodes) was present in 37(84%) patients (median number of proximal episodes = 6). Manometric parameters are similar in the presence or absence of proximal reflux. There is not a correlation between the UES length and UES basal pressure. In conclusion, our results show that: (1) the manometric profile of the UES in patients with GERD is characterized by a short and hypotonic UES in half of the patients; (2) this profile is more pronounced in patients with extraesophageal symptoms; and (3) neither the presence of proximal reflux nor reflux pattern bring a different manometric profile.

Comparison of idiopathic achalasia and Chagas' disease esophagopathy at the light of high-resolution manometry.

The comparison between idiopathic achalasia (IA) and Chagas' disease esophagopathy (CDE) may evaluate if treatment options and their outcomes can be accepted universally. This study aims to compare IA and CDE at the light of high-resolution manometry. We studied 86 patients with achalasia: 45 patients with CDE (54% females, mean age 55 years) and 41 patients with IA (58% females, mean age 49 years). All patients underwent high-resolution manometry. Upper esophageal sphincter parameters were similar (basal pressure CDE = 72 ± 45 mmHg, IA = 82 ± 57 mmHg; residual pressure CDE = 9.9 ± 9.9 mmHg, IA = 9.8 ± 7.5 mmHg). In the body of the esophagus, the amplitude was higher in the IA group than the CDE group at 3 cm (CDE = 15 ± 14 mm Hg, IA = 42 ± 52 mmHg, P = 0.003) and 7 cm (CDE = 16 ± 15 mmHg, IA = 36 ± 57 mmHg, P = 0.04) above the lower esophageal sphincter (LES). The LES basal pressure (CDE = 17 ± 16 mmHg, IA = 40 ± 22 mmHg, P < 0.001) and residual pressure (CDE = 12 ± 11 mmHg, IA = 27 ± 13 mmHg, P < 0.001) were also higher in the IA group. Our results show that: (i) there is no difference in regards to the upper esophageal sphincter; (ii) higher pressures of the esophageal body are noticed in patients with IA; and (iii) basal and residual pressures of the LES are lower in patients with CDE. Our results did not show expressive manometric differences between IA and CDE. Some differences may be attributed to a more pronounced esophageal dilatation in patients with CDE.

Esophageal diverticula and cancer.

Esophageal diverticula are rare. The association of cancer and diverticula has been described. Some authors adopt a conservative non-surgical approach in selected patients with diverticula whereas others treat the symptoms by diverticulopexy or myotomy only, leaving the diverticulum in situ. However, the risk of malignant degeneration should be may be taken in account if the diverticulum is not resected. The correct evaluation of the possible risk factors for malignancy may help in the decision making process. We performed a literature review of esophageal diverticula and cancer. The incidence of cancer in a diverticulum is 0.3-7, 1.8, and 0.6% for pharyngoesophageal, midesophageal, and epiphrenic diverticula, respectively. Symptoms may mimic those of the diverticulum or underlying motor disorder. Progressive dysphagia, unintentional weight loss, the presence of blood in the regurgitated material, regurgitation of peaces of the tumor, odynophagia, melena, hemathemesis, and hemoptysis are key symptoms. Risk factors for malignancy are old age, male gender, long-standing history, and larger diverticula. A carcinoma may develop in treated diverticula, even after resection. Outcomes are usually quoted as dismal because of a delayed diagnosis but several cases of superficial carcinoma have been described. The treatment follows the same principals as the therapy for esophageal cancer; however, diverticulectomy is enough in cases of superficial carcinomas. Patients must be carefully evaluated before therapy and a long-term follow-up is advisable.

Postprandial proximal gastric acid pocket and gastroesophageal reflux disease.

An unbuffered layer of acidity that escapes neutralization by food has been demonstrated in volunteers and gastroesophageal reflux disease patients. This postprandial proximal gastric acid pocket (PPGAP) is manometrically defined by the presence of acid reading (pH<4) in a segment of the proximal stomach between nonacid segments distally (food) and proximally (lower esophageal sphincter or distal esophagus). The PPGAP may have important clinical implications; however, it is still poorly understood. Gastric anatomy and physiology seem to be important elements for PPGAP genesis. Gastric operations and acid suppression medications may decrease distal - proximal intragastric acid reflux and help control gastroesophageal reflux.

Postprandial proximal gastric acid pocket in patients after distal gastrectomy.

BACKGROUND: An unbuffered postprandial proximal gastric acid pocket (PPGAP) has been noticed in the majority of normal individuals and patients with gastroesophageal reflux disease. The role of gastric anatomy, specifically the antrum, in the physiology of the PPGAP is not yet fully elucidated. This study aims to analyze the presence of PPGAP in patients submitted to distal gastrectomy. METHODS: A total of 15 patients who had a distal gastrectomy plus DII lymphadenectomy and Roux-en-Y reconstruction for gastric adenocarcinoma (mean age 64.3±8.4 years, 12 females) were studied. All patients were free of foregut symptoms after the operation. Patients underwent a high-resolution manometry. A station pull-through pH monitoring was performed from 5cm below the lower border of the lower esophageal sphincter (LBLES) to the LBLES in increments of 1cm in a fasting state and 10min after a standardized fatty meal. Postprandial proximal gastric acid pocket was defined by the presence of acid reading (pH<4) in a segment of the proximal stomach between non-acid segments distally (food) and proximally (LBLES). The PPGAP extent was recorded. The protocol was approved by local ethics committee. Key Results Acidity was not detected in the stomach of nine patients before meal. After meal, PPGAP was not found in three patients. In three patients (20%), a PPGAP was noted with an extension of 1, 1 and 3cm. CONCLUSIONS & INFERENCES: In conclusion, PPGAP is present in a minority of patients after distal gastrectomy; this finding may suggest that the gastric antrum may play a role in the genesis of the PPGAP.

Effects of ursodeoxycholic acid in esophageal motility and the role of the mucosa. An experimental study.

Esophageal motor abnormalities are frequently found in patients with gastroesophageal reflux disease. The role of bile in reflux-induced dysmotility is still elusive. Furthermore, it is questionable weather mucosal or muscular stimulation leads to motor dysfunction. The aims of this study were to analyze (i) the effect of bile in the amplitude of esophageal contractions; and (ii) the effect of mucosal versus muscular stimulation. Eighteen guinea pig esophagi were isolated, and its contractility assessed with force transducers. Three groups were studied. In group A (n= 6), the entire esophagus was incubated in 100 µmL ursodeoxycholic acid for 1 hour; in group B (n= 6) the mucosal layer was removed and the muscular layer incubated in 100 µmL ursodeoxycholic acid for 1 hour; and in group C (n= 6) (control group) the entire esophagus was incubated in saline solution. In all groups, five sequential contractions induced by 40 mm KCl spaced by 5 minutes were measured before and after incubation. Contractions amplitudes before incubation were 1.319 g, 0.306 g, and 1.795 g, for groups A, B, and C, respectively. There were no differences between groups A and C (P= 0.633), but there were differences between groups A and B (P= 0.039), and B and C (P= 0.048). After incubation amplitude of contraction were 0.709 g, 0.278 g, and 1.353 g for groups A, B, and C, respectively. Only group A showed difference when pre and post-stimulation amplitudes were compared (P= 0.030). Our results show that (i) bile exposure decreases esophageal contraction amplitude; and (ii) the esophageal mucosa seems to play an important role in esophageal motility.

Postprandial proximal gastric acid pocket and gastric pressure in patients after gastric surgery.

BACKGROUND: An unbuffered postprandial proximal gastric acid pocket (PPGAP) has been demonstrated in normal individuals (NI) and patients with gastro-esophageal reflux disease (GERD). The role of gastric anatomy and gastric motility in the physiology of the PPGAP remains elusive. This study aims to analyze the correlation of PPGAP with proximal gastric pressure after gastric surgery. METHODS: A total of 26 individuals were studied: eight patients after open Roux-en-Y gastric bypass (RYGB) for morbid obesity, six patients after laparoscopic Nissen fundoplication for GERD, seven patients after open subtotal gastrectomy for gastric cancer and five NI. Patients underwent high resolution manometry to identify the location of the lower border of the lower esophageal sphincter (LBLES) and measure gastric pressure 1, 2, 3, 4 and 5 cm below the LBLES, immediately before swallow and after the end of the LES relaxation. A station pull-through pH monitoring was performed in all but NI, from 5 cm below the LBLES to the LBLES in increments of 1 cm in a fasting state and 10 min after a standardized fatty meal. KEY RESULTS: Our results show that: (i) proximal gastric pressures are lower after swallow compared with before swallow in NI; (ii) patients after gastric surgery tend to have higher gastric pressure before and lower after swallow compared with NI and (iii) patients after RYGB with PPGAP have an increased gastric pressure after swallows in the segment where the PPGAP is noticed. CONCLUSIONS & INFERENCES: Gastric motility may play a role in the genesis of PPGAP in patients after RYGB. The contribution of gastric motility for the genesis of PPGAP is still elusive in other patients.

When did the esophagus start shrinking? The history of the short esophagus.

Even though the history of this condition extends for almost 100 years, the short esophagus (SE) is still one of the most controversial topics in esophageal surgery with its existence still denied by some distinguished surgeons. We reviewed the evolution behind the diagnosis and treatment of the SE and the persons who wrote its history, from the first descriptions by radiologists, endoscopists, and surgeons to modern treatment.