Two high-risk patients underwent an endovascular stent-grafting for thoracoabdominal aortic aneurysms (TAAA) following bypass-grafting to the visceral arteries. The first patient was a 73-year-old woman with severe ischemic heart disease (IHD) and chronic respiratory failure. The second patient was a 59-year-old woman with myelodysplastic syndromes (MDSs) and hepatic cell carcinoma (HCC). In general, TAAA is not considered to be indicated for endovascular stent-grafting because of the need to revascularize the visceral vessels. However, in some selected cases, such as the two cases presented herein, endovascular stent-grafting combined with bypass-grafting of the visceral arteries can be a feasible and a less-invasive alternative to conventional surgery.