Between January, 1982, and December, 1987, 14 patients failed to approximate sternum after open-heart surgery in infants and children. The indications for keeping sternum open were enlarged heart, myocardial edema, severe depression of myocardial contractility and reduced lung compliance due to pulmonary edema. Of the 14 patients, 9 underwent delayed sternal closure between 2nd and 13th postoperative day, and 4 were long-term survivals. All the rest of five patients who were left their sternum open, died of intractable cardiac failure within 16th postoperative day. During the sternum open, three patients suffered from complications-myocardial bleeding in one, and mediastinitis in two. But none of them directly related to the death, and one patient with mediastinitis successfully healed with closed mediastinal irrigation. Although the employment of the delayed sternal closure is rare and limited to the patient with severe heart failure, its judicious use adds advantages in the management of low cardiac output state in infants and children immediately postoperative period.