The extended left atriotomy which combine the standard approach with the superior approach by concomitant temporary division of the superior vena cava is a safe and useful method especially in the case of small atrium or in the case of having anatomically abnormal situation of the left atrium. The technical detail was introduced here, and it is a modification of that reported by Selle and Kyger. We used this technique in three cases. The first was corrected transposition of the great arteries which required prosthetic replacement of the left sided atrioventricular valve. The second and third cases were mitral valve insufficiency with small left atrium which were performed mitral annuloplasty and caspal repair. All three patients have done well without SVC stenosis and perioperative morbidity like arrhythmia or bleeding.