A 39-year-old pregnant patient with acute appendicitis was planned for emergency laparoscopic appendectomy in the second trimester of pregnancy. Preoperative two-dimensional transthoracic echocardiography revealed asymptomatic cor triatriatum sinisiter (CTS). dividing left atrium into two chambers. There was no associated cardiac anomaly. https://leoners.shop/product-category/full-mattress/