The Clinical Impact of Tonometry on the Diagnosis and Treatment of Gastrointestinal Ischemia

This thesis focuses on two issues: 1) the clinical value of gastric exercise tonometry (GET), and 2) the development of reliable prolonged tonometry, including postprandial measurement, and its potential in patients suspected of gastrointestinal ischemia. Including GET in the analysis of patients with solitary celiac artery stenosis had major clinical impact. The GET results enabled us to distinguish between patients with and without gastric ischemia. The clinical improvement after vascular treatment in ischemic patients was sustained for up to 4 years, and compares favorably to earlier reports. These results put the single vessel splanchnic syndrome on the map as a clinical entity. The ability of GET to separate ischemic form non-ischemic patients proved beneficial in the large cohort of patients with both single-and multi-vessel splanchnic stenoses as well. Similar to the single-vessel patients, GET identified patients with gastrointestinal ischemia, subsequent treatment resulted in good results on mid-term follow-up. The single-and multi-vessel patients differed significantly in patient characteristics, clinical presentation, morbidity and mortality (before and after treatment). This leads to the notion that the chronic splanchnic syndrome (CSS) has to be divided into two different entities, with different diagnostic and therapeutic approach, urgency, and goals of treatment. Prolonged tonometry, including postprandial measurements, proved feasible in healthy subjects when in vitro tested standard meals were taken and high dose acid suppression was administered. From this study ‘normal’ values were obtained. Using these normal values in a cohort of patients, the accuracy for ischemia detection of prolonged tonometry showed acceptable results. Careful and prospective studies are clearly needed to confirm these first results before prolonged tonometry can be advocated in patients suspected for CSS

Therapeutic balloon-assisted enteroscopy

Since the introduction of the first balloon-based enteroscopic technique in 2001, therapeutic balloon-assisted enteroscopy (BAE) using either the single or double balloon enteroscopy technique (respectively SBE and DBE) has evolved rapidly. Argon plasma coagulation (APC), polypectomy, dilation therapy of strictures, and therapy of the pancreatico-biliary system in patients with surgical altered proximal intestinal anatomy: all have been successfully introduced to treat pathological findings in all segments of the small bowel. The clinical impact of treatment of vascular malformations, strictures caused by chronic inflammation (especially Crohn's disease) and polypectomy therapy (especially in the Peutz-Jeghers syndrome) seems evident. The decrease of, often repeated, surgical therapy after successful therapeutic BAE in the latter 2 patient groups appears to be a big step forward in treatment. The development of newer enteroscopes, specialized equipment and improved sedation of patients adds positively to the clinical management of undergoing therapeutic BAE. The overall complication rate of therapeutic BAE seems acceptable, but is higher compared to therapeutic colonoscopy which needs further attention in future

Patients with chronic gastrointestinal ischemia have a higher cardiovascular disease risk and mortality

Objectives: We determined the prevalence of classical risk factors for atherosclerosis and mortality risk in patients with CGI. Methods: A case-control study was conducted. Patients referred with suspected CGI underwent a standard work-up including risk factors for atherosclerosis, radiological imaging of abdominal vessels and tonometry. Cases were patients with confirmed atherosclerotic CGI. Controls were healthy subjects previously not known with CGI. The mortality risk was calculated as standardized mortality ratio derived from observed mortality, and was estimated with ten-year risk of death using SCORE and PREDICT. Results: Between 2006 and 2009, 195 patients were evaluated for suspected CGI. After a median follow-up of 19 months, atherosclerotic CGI was diagnosed in 68 patients. Controls consisted of 132 subjects. Female gender, diabetes, hypercholesterolemia, a personal and family history of cardiovascular disease (CVD), and current smoking are highly associated with CGI. After adjustment, female gender (OR 2.14 95% CI 1.05-4.36), diabetes (OR 5.59, 95% CI 1.95-16.01), current smoking (OR 5.78, 95% CI 2.27-14.72), and history of CVD (OR 21.61, 95% CI 8.40-55.55) remained significant. CGI patients >55 years had a higher median ten-year risk of death (15% vs. 5%, P = 0.001) compared to controls. During follow-up of 116 person-years, standardized mortality rate was higher in CGI patients (3.55; 95% CI 1.70-6.52). Conclusions: Patients with atherosclerotic CGI have an increased estimated CVD risk, and severe excess mortality. S