A 51-year-old man with osteogenesis imperfecta and who had aortic regurgitation was admitted to our hospital for aortic valve replacement. His height was 146cm and his weight was 49kg. The patient had suffered from bone fractures several times since childhood. Bone deformity, blue sclera and his status were clinically indicative of osteogenesis imperfecta. Aortic valve replacement with a 25mm SJM^® prosthetic valve was successfully performed for aortic valve insufficiency and slight annulo-aortic ectasia. Soft tissues and the sternum were fragile. Pathological examination (Elastica-Masson stain) of the aortic valve and left ventricular wall revealed a loss of fibrous tissues and remarkable thickening due to elastic fibers. The patient was discharged 31 days after surgery. Osteogenesis imperfecta is one of the collagen diseases caused by gene abnormality, in which fragile bones are easily fractured. Cardiovascular disease is rarely associated with it and the surgery-related mortality rate is reported to be approximately 30%, due to bleeding.

We report a case of ulcerative colitis (UC) after mitral valve replacement (MVR) surgery due to infective endocarditis (IE). A 59-year-old woman underwent MVR for mitral regurgitation due to IE. Six days after the surgery, melena was observed suddenly, and she received a blood transfusion. Ulcer and erosion were observed in the rectum 5 to 10 cm from the anal ring by endoscopy. We changed her antibiotic treatment and stopped warfarin potassium. Heparin sodium was started 2 days after melena. We diagnosed ulcerative colitis from the finding of the rectal lesion and biopsy. We gave mesalazine and betamethasone as treatment for UC. The patient's condition improved and her general condition stabilized. She was discharged 36 days after surgery.

Y-graft replacement was successfully performed in a patient aged 93 years with ruptured infrarenal abdominal aortic aneurysm. The patient was in shock on arrival and underwent an emergency operation with the administration of cathecholamines. The ruptured infrarenal abdominal aortic aneurysm with a large hematoma, which was located in the area of the left common iliac artery, was 10cm in the maximum diameter. The bilateral common iliac arteries were strongly calcified and occluded. The distal end of the graft was anastomosed to the external iliac artery. The patient's postoperative course was uneventful.