Background Open heart surgery during pregnancy is relatively rare at home and abroad, and there is a higher risk and probability of maternal and infant death. How to carry out heart valve replacement under cardiopulmonary bypass (CPB) under the premise of ensuring the safety of mother and child is the focus of attention at home and abroad. Case introduction We reported four cases of cardiac surgeries under CPB during pregnancy performed in our hospital from March 2020 to March 2021. Two of the patients continued their pregnancy after cardiac surgery under CPB. Three patients had infective endocarditis and the other one had an ascending aortic aneurysm. Three patients underwent heart valve placement with the mechanical mitral valve when the other one underwent Bentall surgery. The operations of four cases were all successful, and further follow-up evaluation of the pregnant women and fetuses showed no abnormalities. The patients' detailed information is shown in the following table. Conclusion Heart disease during pregnancy should be treated actively and proactively when the patient has obvious symptoms. Heart valve replacement under CPB will be the first choice, and this may become the primary surgical treatment for symptomatic heart disease during pregnancy.

Background: Open heart surgery during pregnancy is relatively rare at home and abroad, with high risk and high probability of maternal and infant death. How to carry out heart valve replacement under cardiopulmonary bypass (CPB) under the condition of ensuring the safety of mother and child is a focus of attention at home and abroad. Case introduction: We reported four cases of pregnant women who underwent cardiac surgeries under CPB during pregnancy in our hospital. Three cases had infective endocarditis (IE), who underwent heart valve placement with mechanical mitral valve, and one case with ascending aortic aneurysm underwent Bentall surgery. The operations of four cases were successful, and further follow-up evaluation of the pregnant women and fetus showed no abnormality. Patients' details are available in the following table. Conclusion: Actively and proactively for heart disease during pregnancy with obvious symptoms. Cardiac valve replacement under CPB will be the first choice, and this may become the primary surgical treatment for symptomatic heart diseases during pregnancy.