Arterial switch operation: progress in approaching a zero mortality rate

Results A total of 163 ASO procedures of all types were identified. The diagnoses were; TGA/IVA 88, TGA/VSD 53, TGA/ arch 5, TGA/VSD/arch 4, Taussig Bing 10, Taussig Bing/ arch 9, for a total of 169, ten patients underwent a staged repair in preparation for ASO of which 4 died. One died before intervention, one did not undergo ASO operation at our institution. Total mortality for all ASO procedures was 23% (38/163). Mortality over time decreased from 100% in 1996 to 0% in 54 consecutive patients between June 2009 and December 2012. A linear relationship in mortality was noted over time, with a correlation coefficient of 0.88. Analysis of other factors including; coronary anatomy, type of ASO, cross-clamp time did not reveal significant differences. The ASO/VSD operation was initially a risk factor with an overall mortality of 28% (15/53), however this disappeared over time. Conclusion A significant learning curve is required to achieve low mortality in the ASO. Early failure should not discourage pursuit of improved results.