A 70-year-old male patient with severe cardiac dysfunction underwent carotid artery stenting for severe left carotid artery stenosis under monitored anesthetic care. He was sedated with propofol and fentanyl, and was monitored with ECG, pulse-oximeter and direct blood pressure measurement. He breathed spontaneously without severe hypoxia during the procedure. Followed by insertion of transient ventricular pacing wire against expected severe bradycardia, a guidewire was introduced into left internal carotid artery lesion via the right femoral artery. Soon after dilating the stenotic portion with a ballon catheter, sudden hypotension and bradycardia were recognized, which were successfully managed with bolus injections of vasoconstrictors and atropine sulphate. Even after stenting, hypotension continued for two days in spite of continuous administration of dopamine. Postoperative examination showed that the blood flow of the left carotid artery was doubled. Two weeks after the operation, he was discharged uneventfully.