CARTER (London). 'Prognosis Following Balloon Atrial Septostomy and Subsequent Management of Trans-

position of the Great Arteries. ' In transposition of the great arteries the pulmonary and systemic circula-tions are independent; but there must be an adequate communication between the two circulations, preferably at atrial level. An adequate atrial septal defect may be created satisfactorily during the first 3 months of life by the technique of balloon atrial septostomy described by Rashkind and Miller (1966). This procedure carries a very much lower mortality in this age group than the Blalock-Hanlon operation. During the ensuing months following satisfactory palliation there is a continuing declining survival, indicating the need for further treatment. Analysis of the first 150 operations for rearrangement of atrial flow by the Mustard technique performed since February 1965 shows that in simple transposition of the great arteries (i.e. with no additional lesions than an atrial communication) there is a 90 % operative survival rate; age range 3 months to 20 years. The survival rate is similar if the infant group (children less than one year old) is separated out. It is thus suggIsted that in simple transposition of the great arteries successful palliation by balloon septostomy should be followed by rearrangement of atrial flow at about one year of age (when most of the infants weigh 5-7 kg), as the survival rate from operation is at least as high as the natural survival rate during the ensuing year. REFERENCES Rashkind, W. J., and Miller, W. W. (1966). Creation of an atrial septal defect without thoracotomy. A palliative approach to complete transposition of the great arteries. Journal of th