We report two cases of an abdominal aortic aneurysm, one with congestive heart failure, and the other with a dissecting aortic aneurysm (type IIIb), who underwent an aorto-bifemoral bypass operation under a temporary external axillofemoral bypass. In one patient (Case 1, a 74-year-old male), who had an abdominal aortic aneurysm with congestive heart failure due to aortic valve insufficiency and stenosis, perioperative transesophageal echocardiography demonstrated that, with a temporary external axillofemoral bypass, the regurgitant doppler signal was unchanged during the cross-clamping period of the abdominal aorta. In the other patient (Case 2, a 71-year-old male), who had a dissecting thoracoabdominal aortic aneurysm with the lower abdominal aorta having a true aneurysm formation, the transesophageal echocardiography demonstrated that, with a temporary external axillofemoral bypass, the false lumen of the dissecting thoracic aneurysm had no change in size during the cross-clamping period of the abdominal aorta. Thus, a temporary external axillofemoral bypass might avoid any unfavorable hemodynamic effect during and after the abdominal aortic clamping in patients suffering from an abdominal aortic aneurysm with cardiovascular complications.