부산대학교 도서관

Aortic stenosis is an abnormal narrowing of the aortic valve, which controls blood flow between the heart and the main systemic artery (aorta). This defect is sometimes seen in children. In severe cases, treatment must be effected to widen the opening of the valve. Most treatments have involved a variation of valvotomy, in which an incision is made in the valve directly. One problem with this has been a high mortality among children younger than one year old who undergo the procedure. Percutaneous balloon dilatation, whereby a balloon is inserted into the opening and inflated, has also been tried on young children, but this, too, is associated with a high mortality. This study examined the success of one type of aortic valvotomy performed on young children at one facility. The procedure involved an open heart surgical technique of valvotomy, with patients supported by conventional cardiopulmonary bypass machines (in which the blood is mechanically routed outside the heart/lung system). This procedure was performed on 13 babies with an average age of 14 days who had critical aortic stenosis. The operation was initially successful in all 13 patients. One child died 38 days after the operation from an unrelated cause and another died over two years later after aortic valve replacement surgery. Long-term follow-up in the surviving children showed abnormalities in the degree of thickening of the left ventricle during the contraction phase of the heart beat. The subsequent thinning of the wall during the rest phase was also abnormal in some of the children. Peak instantaneous flow (Doppler) gradients (pressure differences across the valve) were below normal, less than 70 mm Hg, in seven patients. The results showed that mortality from the procedure itself was very low, but that long-term follow-up is required because many patients have problems that recur a few years after the operation. These patients can be treated with balloon dilatation. (Consumer Summary produced by Reliance Medical Information, Inc.)