This is a first stage procedure wherein patients who have very high body mass index (BMI) or severe heart or lung disease usually get relief from minor operations like the sleeve gastrectomy. Complications may occur if the patient has excessively large liver or extensive scar tissue to the intestines which make the gastric bypass impossible. In such cases, sleeve gastrectomy – a restrictive procedure – is followed, since it reduces the size of the stomach and limits your food intakes. During sleeve Gastrectomy, about 75% of the stomach is removed, leaving just a narrow tube (sleeve). The treatment is done by making five or six small incisions in the abdomen and is helpful for patients with severe heart or lung diseases.