[Complete correction of Fallot's tetralogy with a Waterston shunt]

The influence of a Waterston shunt on the mortality in complete correction of Fallot's tetralogy varies from series to series. Some authors believe that it has no influence and others, on the contrary, believe it plays an important role to the point of recognising a particular premonitory syndrome of pulmonary hypertension and a low output state. This divergence of opinion in patients with comparable lesions is surprising, and cannot always be explained by poor surgical indications (irreversible pulmonary hypertension) or by problems of surgical technique. In our experience the conditions of cardiopulmonary bypass are of prime importance and we believe that the common factor in surgical failure is poor myocardial protection. This point of view is suggested by our present results in the correction of moderate and severe forms of Fallot's tetralogy under cardioplegia and seems to be reinforced by the results of extensive repair in forms with a Waterston shunt, said to be high risk procedures, that is to say with considerable asymmetry of the pulmonary vascularisation by stenosis of the right main pulmonary artery.