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Biomedical subjects

J J Kolkman

Publications and source records attributed to J J Kolkman.

At least 19 recordsLinked to original sources

Clinical significance of splanchnic artery stenosis.

BACKGROUND: The clinical relevance of splanchnic artery stenosis is often unclear. Gastric exercise tonometry enables the identification of patients with actual gastrointestinal ischaemia. A large group of patients with splanchnic artery stenosis was studied using standard investigations, including tonometry. METHODS: Patients referred with possible intestinal ischaemia were analysed prospectively, using duplex imaging, conventional abdominal angiography and tonometry. All results were discussed within a multidisciplinary team. RESULTS: Splanchnic stenoses were found in 157 (49.7 percent) of 316 patients; 95 patients (60.5 percent) had one-vessel, 54 (34.4 percent) two-vessel and eight (5.1 percent) had three-vessel disease. Chronic splanchnic syndrome was diagnosed in 107 patients (68.2 percent), 54 (57 percent) with single-vessel, 45 (83 percent) with two-vessel and all eight with three-vessel stenoses. Treatment was undertaken in 95 patients, 62 by surgery and 33 by endovascular techniques. After a median follow-up of 43 months, 84 percent of patients were symptom free. CONCLUSION: Gastric exercise tonometry proved crucial in the evaluation of possible intestinal ischaemia. Comparing patients with single- and multiple-vessel stenoses, there were significant differences in clinical presentation and mortality rates.

Adolescent↗

Dutch endoscopic capacity in the era of colorectal cancer screening.

BACKGROUND: Future colorectal cancer (CRC) screening programmes should not (greatly) interfere with regular health care. Hence, we analysed the Dutch endoscopic practice to provide a clear insight into endoscopic workload and manpower with a special emphasis on the current ability to facilitate a successful implementation of a faecal occult blood test (FOBT)-based nationwide CRC screening programme. METHODS: A questionnaire was sent to all Dutch endoscopy units (n = 100) in the spring of 2005. The questionnaire included topics ranging from the numbers and specifications of endoscopies performed in 2004 and the numbers of endoscopists per unit to expected vacancies for gastroenterologists and waiting times. RESULTS: The response rate was 98%, representing a total of 49,253 hospital beds. overall, a 26% increase in the number of endoscopies from 325,000 in 1999 to almost 410,000 in 2004 was found, accompanied by a 25% increase in manpower. The total number of endoscopists was 598. regional differences were observed in the number of endoscopists, the total number of endoscopies and colonoscopies, and the number of endoscopies per endoscopist. A biannual FOBT-based screening programme would yield an additional workload of 25,385 colonoscopies a year amounting to a 22% increase in the total number of colonoscopies performed. However, the workload per unit would only have to increase by five extra colonoscopies a week. CONCLUSION: Whereas an FOBT-based CRC screening programme is currently feasible without strongly interfering with regular health care, future plans regarding the scale and preferred mode of screening should incorporate solid data on the (regional) endoscopic capacity and manpower needed for a successful implementation.

Colorectal Neoplasms↗

Microscopic colitis: prevalence and distribution throughout the colon in patients with chronic diarrhoea.

BACKGROUND: Microscopic colitis presents with chronic diarrhoea with or without abdominal pain. Microscopic colitis is an important cause of chronic diarrhoea. It can be distributed throughout the colon, as well as limited to the right colon. Microscopic colitis is associated with coeliac disease. We studied the prevalence and distribution of microscopic colitis in patients with diarrhoea and normal colonoscopy and we studied the association with coeliac disease. METHODS: Colonoscopy was performed. Biopsies were taken from every segment of the colon. Lymphocytic colitis was defined as the presence of more than 20 lymphocytes per 100 epithelial cells and collagenous colitis was defined as thickening of the basal membrane of more than 10 microm. Upper endoscopy was performed if upper intestinal symptoms were present. If this was the case, small bowel biopsies were taken. RESULTS: Microscopic colitis was found in 13 out of 103 patients. The distribution was diffuse throughout the colon in ten and restricted to the right colon in three patients. In seven patients, upper endoscopy was performed. Marsh I/II lesions were found in six out of seven patients. CONCLUSION: Microscopic colitis was limited to the right colon in 23% of patients. Biopsies of macroscopically normal colonic mucosa in patients with diarrhoea is mandatory.

Adolescent↗

Endovascular treatment of chronic splanchnic syndrome.

OBJECTIVE: The technical and clinical outcome of endovascular revascularization was analyzed in patients with suspicion of chronic splanchnic syndrome (CSS). METHODS: Medical history, duplex, angiography and exercise gastric tonometry suggested CSS in 97 patients. Twenty-seven of them were treated endovascular (one patient had 3-vessel, 12 patients had 2-vessels, 14 patients had 1-vessel CSS). Five patients received previous splanchnic revascularization. Twenty-three patients (85%) had severe co-morbidity: cardiac, pulmonary or cachexia. Endovascular treatment consisted of percutaneous transluminal angiography (PTA) of the coeliac artery (CA) or superior mesenteric artery (SMA) in three and primary balloon expandable stenting in 24 patients (13 CA and 10 SMA solitary, two CA and SMA both, 31 splanchnic arteries in total). RESULTS: Three patients showed procedure related complications (11%). Mean follow-up was 19, range 2-76 months. Two patients died during follow up, both not procedure or CSS related. Five patients had no improvement of symptoms, without evidence of re- or residual stenosis. The primary clinical success was 67%, secondary clinical success was 81%. The primary patency was 81% and secondary patency was 100%. CONCLUSION: Endovascular treatment of CSS has a reasonable outcome. It is an alternative to operative treatment, especially in patients with high co-morbidity or limited life expectancy.

Aged↗

Duodenal versus jejunal biopsies in suspected celiac disease.

BACKGROUND AND STUDY AIMS: In the past, small-bowel biopsies for diagnosis of celiac disease were taken from the jejunum with a suction capsule, but nowadays most physicians take endoscopic biopsies from the distal duodenum. To validate that practice we compared the diagnostic yield of endoscopic duodenal biopsies with that of endoscopic jejunal biopsies. In addition, we describe a method of orienting biopsy specimens optimally. PATIENTS AND METHODS: Upper endoscopy was performed with a colonoscope. Four jejunal and four duodenal biopsies were taken and oriented immediately thereafter. The pathologist rated the orientation as poor, adequate, or good, and histopathological results were expressed according to the Marsh classification. Jejunal and duodenal biopsy results were compared. RESULTS: 146 patients were included. Jejunal biopsies were taken in 142 patients, and Marsh I-II lesions were found in 56 and Marsh III lesions in 15 patients. In three patients duodenal biopsies were normal while jejunal biopsies showed Marsh I-II lesions. No discrepancies were found in patients with Marsh III lesions. Orientation was good in all biopsies. CONCLUSION: Duodenal biopsies are sufficient to diagnose full-blown celiac disease (Marsh III), but Marsh I-II lesions may be missed in some cases.

Adult↗

Clinical approach to chronic gastrointestinal ischaemia: from 'intestinal angina' to the spectrum of chronic splanchnic disease.

Stenotic disorders of the splanchnic arteries are not rare, and it is generally assumed that symptoms are rare in patients with a single splanchnic stenosis, and even in patients with multiple-vessel stenoses. Currently, only gastric exercise tonometry aids the diagnostic evaluation, as it indicates actual ischaemia. Patients with stenotic disorders without complaints are referred to as having chronic splanchnic disease (CSD) and those with ischaemic complaints as having chronic splanchnic syndrome (CSS). The classical presentation of CSS, including the triad postprandial pain, weight loss and upper abdominal bruit, is also known as 'intestinal angina'. From the experience of our multidisciplinary working team on gastrointestinal ischaemia in 110 patients with stenoses of at least one splanchnic artery, two different clinical patterns were observed. In our series approximately 60% of patients with single-vessel stenoses, including the coeliac artery compression syndrome, have CSS. They have fewer complications, very low mortality, but most can be successfully treated by stenting or surgical treatment. Patients with multivessel splanchnic stenoses have more classical ischaemic complaints. Progression to a bowel infarction was seen in 34%, and mortality was 21%, mostly from bowel or myocardial infarction. Treatment should be tailored based upon perioperative risk assessment and local vascular anatomy. This may consist of autologous arterial bypass of one or two vessels, preferably antegrade. stenting or a combination of both. This differentiation between single- and multivessel splanchnic disease has considerable consequences for optimal work-up and treatment.

Celiac Artery↗

Cure of Helicobacter pylori infection in patients with reflux oesophagitis treated with long term omeprazole reverses gastritis without exacerbation of reflux disease: results of a randomised controlled trial.

BACKGROUND: Helicobacter pylori gastritis may progress to glandular atrophy and intestinal metaplasia, conditions that predispose to gastric cancer. Profound suppression of gastric acid is associated with increased severity of H pylori gastritis. This prospective randomised study aimed to investigate whether H pylori eradication can influence gastritis and its sequelae during long term omeprazole therapy for gastro-oesophageal reflux disease (GORD). METHODS: A total of 231 H pylori positive GORD patients who had been treated for > or =12 months with omeprazole maintenance therapy (OM) were randomised to either continuation of OM (OM only; n = 120) or OM plus a one week course of omeprazole, amoxycillin, and clarithromycin (OM triple; n = 111). Endoscopy with standardised biopsy sampling as well as symptom evaluation were performed at baseline and after one and two years. Gastritis was assessed according to the Sydney classification system for activity, inflammation, atrophy, intestinal metaplasia, and H pylori density. RESULTS: Corpus gastritis activity at entry was moderate or severe in 50% and 55% of the OM only and OM triple groups, respectively. In the OM triple group, H pylori was eradicated in 90 (88%) patients, and activity and inflammation decreased substantially in both the antrum and corpus (p<0.001, baseline v two years). Atrophic gastritis also improved in the corpus (p<0.001) but not in the antrum. In the 83 OM only patients with continuing infection, there was no change in antral and corpus gastritis activity or atrophy, but inflammation increased (p<0.01). H pylori eradication did not alter the dose of omeprazole required, or reflux symptoms. CONCLUSIONS: Most H pylori positive GORD patients have a corpus predominant pangastritis during omeprazole maintenance therapy. Eradication of H pylori eliminates gastric mucosal inflammation and induces regression of corpus glandular atrophy. H pylori eradication did not worsen reflux disease or lead to a need for increased omeprazole maintenance dose. We therefore recommend eradication of H pylori in GORD patients receiving long term acid suppression.

Adult↗

[Calprotectin: a fecal marker for diagnosis and follow-up in patients with chronic inflammatory bowel disease].

Chronic inflammatory bowel disease (IBD) is characterised clinically by periods of well being interspersed by exacerbations of disease activity. Differentiation between IBD and less severe disorders such as irritable bowel syndrome requires invasive and expensive diagnostic procedures. Diagnostic differentiation between active disease, symptoms due to residual constriction of the fibrotic lumen and functional symptoms is a well-known problem. There are not yet any laboratory parameters with sufficient discrimination in terms of sensitivity and specificity. Colonoscopy and histopathological examination remain the gold standards: in Crohn's disease this may be complex due to the variable localisation of the inflammatory process. Abdominal scintigraphic procedures, although informative, are complex and expensive. The recent assessment of faecal calprotectin, a calcium- and zinc-binding anti-inflammatory protein found in neutrophilic granulocytes and monocytes, offers an attractive alternative as an index of intestinal inflammation. We measured this stable marker in random stool samples from 187 patients including healthy volunteers, patients with endoscopically classified active IBD or IBD in remission, and patients with other gastrointestinal disorders. Disease activity was monitored by clinical symptoms, blood tests and endoscopy. Our results confirm previous literature findings that faecal calprotectin is a promising and useful non-invasive tool in the screening of patients presenting with abdominal pain and diarrhoea. Moreover, calprotectin seems helpful in differentiating between active and non-active IBD and possibly also in the monitoring of disease activity.

Biomarkers↗

[Gastrointestinal surgery and gastroenterology. XIV. Mesenteric abnormalities in generalised vascular disease].

Various forms of vasculitis may result in mesenteric ischaemia, ischaemic colitis or aneurysm formation in the aorta or intestinal blood vessels. Vasculitides may involve large- and/or medium-sized vessels, medium- and/or small-sized vessels, or small-sized vessels only. It is essential to differentiate between the different forms of vasculitis since diagnostic tests and therapies differ greatly. Gastrointestinal manifestations of vasculitis can generally be detected using angiography, digital subtraction angiography and/or magnetic resonance angiography (MRA). Various laboratory tests are helpful in establishing the diagnosis in patients in whom vasculitis is clinically suspected. In addition, the diagnosis should be confirmed using histology or angiography if possible. Treatment of vasculitis not caused by chronic infection consists of high dose corticosteroids and, in the case of polyarteritis nodosa or vasculitis associated with anti-neutrophil cytoplasmic antibodies (ANCA), cyclophosphamide.

Aneurysm↗

Change in anatomic distribution and incidence of colorectal carcinoma over a period of 15 years: clinical considerations.

PURPOSE: Colorectal cancer is the second most common cancer in the Netherlands. Its incidence rates are among the highest in Europe. In the past decades, a right-sided shift of the subsite location of colorectal cancer has been reported. These changes in anatomic distribution might have clinical implications for the use of diagnostic or screening tools for colorectal cancer. This study was designed to investigate the change in incidence and anatomic distribution of colorectal cancer in a population over a period of 15 years. METHODS: The incidence of colorectal cancer in an eastern part of the Netherlands (700,000 inhabitants) was determined for two years, 1981 and 1996. From the regional laboratory of pathology, data including age, gender, subsite location, and Dukes classification were collected. The subsite location of colorectal cancer was divided into two groups: proximal and distal (the latter being within sigmoidoscopy reach). RESULTS: No differences in age and gender distribution were found. In 1981, the diagnosis of colorectal cancer was made in 232 patients in this region, and in 1996, it was made in 410 patients. The population remained almost stable during this time. Therefore, the incidence rose from 33 to 55 per 100,000 inhabitants from 1981 to 1996, respectively. In 1981, 25 percent of the carcinomas were proximal (to the sigmoid colon); this increased to 37 percent in 1996 ( P< 0.05). CONCLUSIONS: The incidence of colorectal cancer has almost doubled from 1981 to 1996 in this Dutch region. The proportion of proximal colorectal cancer has increased from 25 to 37 percent. These findings add to the notion that sigmoidoscopy is not the optimal diagnostic or screening tool for colorectal cancer.

Aged↗

Exercise induces gastric ischemia in healthy volunteers: a tonometry study.

Heavy physical exercise may cause gastrointestinal signs and symptoms, and, although splanchnic blood flow may decrease through redistribution by more than 50%, it is unclear whether these signs and symptoms relate to gastrointestinal ischemia. In 10 healthy volunteers, we studied the effect of exercise on gastric mucosal perfusion adequacy using air tonometry. Two relatively short (10 min) exercise stages were conducted on a cycle ergometer, aiming for 80 and 100% of maximum heart rate, respectively. The intragastric-arterial PCO(2) gradient (Delta PCO(2)) was elevated by 1.1 +/- 1.0 kPa over baseline values (-0.1 +/- 0.3 kPa) only after maximal exercise (P < 0.001). Delta PCO(2) positively correlated with the arterial lactate level taken as an index of exercise intensity (Spearman's rank test: r = 0.76, P < 0.0001). By bilinear regression analysis, a lactate level of 12 mmol/l, above which a sharp rise in the Delta PCO(2) occurred, was calculated. We conclude that, in healthy volunteers with normal splanchnic vasculature, gastric ischemia may develop during maximal exercise as judged from intragastric PCO(2) tonometry.

Adult↗

[PCO2 tonometry of the stomach].

Gastrointestinal luminal tonometry is a minimally invasive technique for measuring gastrointestinal ischaemia. Mucosal ischaemia leads to excessive production of tissue CO2 and thus to an increase of luminal PCO2. For this measurement, a nasogastric catheter is introduced with at its end a balloon permeable for CO2, this balloon is filled with air or liquid. After CO2 has diffused from the tissue into the lumen of the balloon, the PCO2 in the liquid or air is determined. Due to uncertainties about physiological background, methodology and clinical usefulness tonometry is not yet widely applied. The recent introduction of automated airtonometry, replacing the laborious and error-prone manual saline technique, makes tonometry more reliable and easier applicable in the clinical situation. Reliable measurements require inhibition of gastric acid production and measurement in a fasting condition. The lumen-blood PCO2 gradient is the most reliable parameter of gastrointestinal mucosal ischaemia. In the past intraluminal pH--calculated from the intraluminal PCO2 measured by tonometry and the bicarbonate concentration in the blood--has been the parameter most often used. Tonometric parameters are reliable indicators of morbidity and mortality in critically ill patients. The effect of 'tonometry-guided' treatment on the morbidity and mortality is still a matter of debate. Other than using tonometry as a global ('hemodynamic') monitoring device, selective monitoring of the regional perfusion of the digestive tract--such as for diagnostic purpose in suspected chronic ischaemia due to splanchnic arterial disease--is a promising new application area.

Carbon Dioxide↗

[Gastrointestinal surgery and gastroenterology. VIII. Gastroenterologic aspects of chronic gastrointestinal ischemia].

The main cause of chronic gastrointestinal ischaemia is atherosclerosis. Stenotic lesions of the mesenteric circulation are relatively common, but lead to chronic ischaemic complaints due to collateral circulation in probably only 2-3 per 100,000 inhabitants per year. The classical presentation (post-prandial abdominal pain, weight loss, upper abdominal souffle) is present in a minority of patients only. Symptoms also occur after exercise. Gastric ulcers and diarrhoea are less frequent. Although patients with 2 and 3 vessel involvement (coeliac artery, superior mesenteric artery and inferior mesenteric artery) usually experience the most severe ischemic complaints, patients with single vessel involvement can also develop symptoms. In the diagnosis of cases with abdominal complaints, factors that aggravate or reduce the complaints anamnestically are the guideline for supplementary diagnostics. The more frequent causes of the symptoms are to be excluded first. Doppler-ultrasonography of the mesenteric vessels can detect most stenotic lesions accurately. To establish the diagnosis visceral angiography is needed. A new method of examination is magnetic resonance angiography (MRA). Another new method is tonometry during exercise: a PCO2 value in the lumen that is higher than that in the blood indicates ischaemia. Non-invasive treatment of chronic gastrointestinal ischaemia is aimed at reduction of the gastrointestinal metabolic workload by smaller meals, at suppression of acid secretion, at inhibition of the secretion of gastric acid and on risk factors for atherosclerosis.

Abdominal Pain↗

Nonvariceal upper gastrointestinal bleeding: differences in outcome for patients admitted to internal medicine and gastroenterological services.

OBJECTIVE: It has been suggested that admission to a gastroenterology service (GAS) is associated with a better prognosis and lower cost for treatment of gastrointestinal (GI) diseases, such as upper GI bleeding (UGB). However, a large potential bias by higher comorbidity on internal medicine services (MED) could not be excluded from these studies. We therefore compared patients with upper GI bleeding admitted to a gastroenterology or internal medicine department, with special emphasis on prognostic factors, such as comorbidity, and outcome. METHODS: Between 1991 and 1995, 322 patients were admitted to our hospital for UGB. Forty-five patients had variceal and 277 patients had nonvariceal upper GI bleeding (NUGB). Of 232 patients with primary NUGB, 125 were admitted to GAS and 93 to MED. The charts of these patients were revised, comorbidity was carefully recorded, and the Rockall risk score was calculated. All deaths were individually classified as unavoidable, mostly due to severe underlying illness, or potentially avoidable. RESULTS: No differences in delay for endoscopy or treatment were observed between GAS and MED. The rebleeding, surgery, and mortality rates in GAS and MED patients were 11.6% versus 11.5% (NS), 7.8% versus 7.3% (NS), and 2.4% versus 10.8% (p = 0.02), respectively. Rockall scores differed between GAS and MED patients (3.1 +/- 1.8 vs 3.7 +/- 1.7, p = 0.02). The mortality rate stratified by Rockall score was lower for the GAS patients. However, individual analysis revealed that only three of 13 deaths were potentially avoidable: two of 10 at the MED and one of three at the GAS. CONCLUSION: The lower mortality among nonvariceal upper GI bleeding patients admitted to a gastroenterological service compared to an internal medicine service was mainly due to lesser comorbidity. This effect was not detected by stratification according to Rockall, but shown with analysis of individual patient charts only. The latter underscores the potential pitfalls when comparing outcome or cost of treatment between different medical services.

Acute Disease↗

Effect of gastric feeding on intragastric P(CO2) tonometry in healthy volunteers.

PURPOSE: The tonometric detection of a high intragastric regional P(CO2) (PrCO2) reflecting an elevated intramucosal P(CO2) can be helpful to diagnose mucosal ischemia, if acid secretion is suppressed to avoid intragastric CO2 production through buffering of acid by bicarbonate in the stomach. It is recommended to perform tonometry in the fasting state, but this may hamper feeding of the critically ill. On the other hand, postfeeding tonometry could serve as a diagnostic stress test because feeding increases mucosal blood flow demand, provided that the meal itself does not hamper diffusion of CO2 from mucosa to tonometer balloon and does not generate intragastric CO2, independently from intramucosal P(CO2). We therefore studied the effect of a standard meal on intragastric PrCO2 tonometry in healthy volunteers with suppression of meal-stimulated gastric acid secretion and, presumably, with an adequate mucosal blood flow reserve. MATERIAL AND METHODS: The gastric juice pH and tonometric PrCO2 were measured in 14 human volunteers, after gastric acid secretion suppression by either ranitidine (100-mg bolus, followed by 25 mg/h i.v., n = 7) or by ranitidine plus pirenzepine (10-mg bolus, followed by 3 mg/h i.v., n=7) to suppress any residual meal-stimulated gastric acid secretion, before and at 30-minute intervals until 120 minutes after oral ingestion of a standard liquid test meal (Pulmocare [Abbott, the Netherlands]; 500 mL, 750 kcal, P(CO2) 5 mm Hg, pH 7.50). RESULTS: The gastric juice pH, which was >4.0 in all individuals throughout the study, and the PrCO2 did not depend on the regimen for gastric acid secretion suppression, and therefore the data were pooled. The PrCO2 (median [range]) after feeding was 69% (56% to 170%) of baseline (42 [37-51] mm Hg) from 0 to 30 minutes (P < .001), 85% (72% to 167%) of baseline from 30 to 60 (P < .05), 97% (57% to 193%) from 60 to 90 minutes, and 112% (97% to 189%) of baseline from 90 to 120 minutes with a rise above baseline in 10 of 14 patients. In vitro, the liquid test meal generated CO2 after adding bicarbonate but not after hydrochloric acid. CONCLUSION: We recommend intragastric tonometry to be performed in the fasting state and discourage tonometry after feeding as a stress test, because a single test meal changes tonometric PrCO2 in a time-dependent manner until 2 hours after gastric feeding of healthy volunteers. The fall in PrCO2 directly after feeding can be attributed to dilution, whereas a rise above baseline in some patients may have been caused, as supported by CO2 production after adding bicarbonate to the test meal in vitro, by CO2 production through buffering of meal-derived acid by gastric bicarbonate, in the absence of stimulated gastric acid secretion by feeding.

Adult↗

Increased gastric PCO2 during exercise is indicative of gastric ischaemia: a tonometric study.

BACKGROUND: Diagnosis of gastric ischaemia is difficult and angiography is an invasive procedure. Angiographic findings may not correlate with clinical importance. AIMS: To investigate whether tonometric measurement of intragastric PCO2 during exercise can be used to detect clinically important gastric ischaemia. METHODS: Fourteen patients with unexplained abdominal pain or weight loss were studied. Splanchnic angiography served as the gold standard. Three patients were studied again after a revascularisation procedure. Gastric PCO2 was measured from a nasogastric tonometer, with 10 minute dwell times, and after acid suppression. Gastric and capillary PCO2 were measured before, during, and after submaximal exercise of 10 minutes duration. RESULTS: Seven patients had normal angiograms; seven had more than 50% stenosis in the coeliac (n=7) or superior mesenteric artery (n=4). Normal subjects showed no changes in tonometry. In patients with stenoses, the median intragastric PCO2 (PiCO2) at rest was 5.2 kPa (range 4.8-11.2) and rose to 6.4 kPa (range 5.7-15.7) at peak exercise; the median intragastric blood PCO2 gradient increased from 0.0 kPa (range -0.8 to 5.9) to 1.7 kPa (range 0.9 to 10.3; p<0.01). Only two subjects had abnormal tonometry at rest; all had supernormal values at peak exercise. The PCO2 gradient correlated with clinical and gastroscopic severity; in patients reexamined after revascularisation (n=3), exercise tonometry returned to normal. CONCLUSION: Gastric tonometry during exercise is a promising non-invasive tool for diagnosing and grading gastrointestinal ischaemia and evaluating the results of revascularisation surgery for symptomatic gastric ischaemia.

Adult↗