A 34-year-old female underwent emergency cesarean section with general anesthesia. The patient was a para 1-0-0-1, referred at 39 weeks in labor with known severe aortic stenosis due to a bicuspid aortic valve. She has been treated with digoxin and furosemide for 5 years. At first, she tried a normal spontaneous vaginal delivery, but dyspnea was aggravated during delivery, so an emergency operation was decided. Anesthesia was induced using ketamine 80 mg, fentanyl 50 microgram and vecuronium 6 mg and maintained with 50% nitrous oxide in oxygen. After fetal delivery and infusion of oxytocin, the systolic blood pressure decreased to 60 mmHg or less, so we injected phenylephrine 100 microgram bolus. However, the blood pressure did not increase, so we injected phenylephrine continuously ( 0.5 microgram/kg/ min). One month postpartum, echocardiography was done. The left ventricle-aortic pressure gradient was 140 mmHg, so the cardiologist recommended an aortic valve replacement operation. She refused the operation and has been medicated with digoxin and furosemide up to date.