[Indications to the surgical treatment of patients with "simple" transposition of the great arteries. Analysis of 302 cases surgically treated according to mustard's technique (author's transl)]

Abstract

Between January 1965 and December 1979, 302 patients underwent Mustard's operation for "simple" transposition of the great arteries (TGA). 31 cases who underwent Senning operation for "simple" TGA and 7 patients with "simple" TGA and severe pulmonary vascular disease, in whom Mustard's operation was performed and a ventricular septal defect created, have not been included in the present series. The patients analysed ranged in age from 3 days to 17 years (mean = 27,6 months) and in weight from 2.7 to 40 Kg (mean = 9.9 Kg). The technique originally described by Mustard was used, with some technical modifications. There were 26 early deaths (early mortality rate = 9%). The hospital mortality was 16% during the period 1965-1969, 75% between 1970 and 1974, while during the last 5 years it was 6%. The hospital mortality was lower among the infants between 6 and 12 months of age (6%), compared with an early mortality rate of 11% among those younger than 6 months and 9% in the age group over 1 year. There were 34 late deaths (12% of the survivors). Reoperation was performed in 42 cases. Forty patients required revision of the inter-atrial baffle for pulmonary and/or caval venous obstruction and 10 of them subsequently died. Post-operative venous obstructions were observed more frequently in patients with dumb-bell shaped dacron patch, which has been since 6 years abandoned. Since the introduction of Brom's trouser shape pericardial patch, venous obstructions are extremely rare. Both patients who underwent reoperation respectively for severe tricuspid valve incompetence and for occlusion of the left pulmonary artery, died early after reoperation. In our Unit, the actual management program for patients with "simple" TGA is the following. We keep to a minimum the degree of invasive investigations, 2 D ECHO diagnoses TGA with great accuracy. At the initial cardiac catheterization, a balloon atrial septostomy (BAS) is performed. A good inter-atrial mixing is usually obtained with balloons sized more than 2.5 ml. Angiocardiography is undertaken only when associated lesions, such as patent ductus arteriosus or aortic coarctation are suspected. If the child improves, complete investigation is performed at 3-4 months of age and the inter-atrial redirection of the venous inflow is scheduled for the age of 8-12 months. If the child fails to improve after BAS or deteriorates during the waiting period, restudy is performed immediately to ensure that additional lesions are not present and that the inter-atrial shunt is adequate. Rather than a surgical atrial septectomy, in this group of cases we prefer an early intracardial total repair, irrespective of age and weight.