A right thoracotomy was used for the reoperation or mitral valve of 15 patients who had previously undergone a cardiac operation through a median sternotomy. In our experience. this approach provided dn excellent exposure of the nlitral valve and easy cannulations of both cavie with minimal dissection, ilvoiding any damage of cardiac and major vessels during re-sternotomy Arterial cannulation was performed in the ascending aorta in 13 patients And in the femoral artery in 2 patients. In earlier cases, venous cannulation was done in the SVC And IVC through the right atrium and snared. In later cases, this could be done without snaginly of both cavae or by placing a silgle light-angled catheter into the right atrium. Crystalloid cardioplegic solution was infused for myocardial protection. Hypothermia was controlled at 20ulcorner$25^{circ}C$. For defibrillation, internal paddles were used In one patient while sterilized external paddles were used in 10 patients. In the remaining four patients. however. the heart beat spontaneously The respirator could be weaned within 48 hours alter the operation and no pulmonary complication was observed. One out of the 15 patients expired due to sudden attack of ventricular tarchycardid developed ten days after the operation, but the rest of the patients were discharged with good condition.