It is a modification of the previous procedures in which a stoma was formed for external drainage or an internal diversion was achieved by terminal ileal bypass. These procedures had documented complications related to stoma or biliary fistulae in case of external biliary drainage and malabsorption and recurrence in ileal bypass procedures.
did an Ileal bypass procedure by excluding 15% of the terminal ileum.
In addition, at least 3 trials with bile acid sequestration have demonstrated reduction in cardiovascular disease events, the POSCH (Partial Ileal Bypass Surgery), Lipid Research Clinics-Coronary Primary Prevention Trial, and Colestipol Trial.
Malabsorptive procedures include bileopancreatic diversion, roux-en y gastric bypass (both restrictive and malabsorptive), and, historically, jejunal ileal bypass. Concern over nutrient deficiencies is one reason jejunal ileal bypass is no longer used.
POSCH was a randomized, controlled clinical trial designed to assess whether the lipid modification induced by partial ileal bypass surgery would have a beneficial effect on subsequent overall mortality, atherosclerotic mortality and morbidity, and changes on sequential coronary arteriograms in hypercholesterolemic survivors of a single myocardial infarction (MI).
Effect of partial ileal bypass surgery on mortality and morbidity from coronary heart disease in patients with hypercholesterolemia.