Sir.—It is reassuring to learn from Vet and Ottenkamp1 that their surgical results in repairing complete atrioventricular septal defects in patients with Down syndrome are good enough to warrant doing this surgery on infants with these diagnoses, although other studies2 indicate an expected surgical mortality of 0.3% to 8%. However, in trying to explain why the authors' surgical mortality was so high in infants with complete atrioventricular septal defect who did not have Down syndrome, much more data are required before the statistics can be used in formulating management strategies. The following comments in particular are noted:
No information is available about the pulmonary pressures and pulmonary vascular resistances in any of the patients despite the great influence these factors exert on operative morbidity and mortality.
The causes of death listed in Vet and Ottenkamp's Table 4 are not specific enough to guide one in