Sternotomy approach for the modified Blalock-Taussig shunt

Since 1990, sternotomy has been the preferred approach for construction of a modified Blalock-Taussig shunt (MBTS) at Children's Hospital, Boston, Mass. In retrospect, we sought to test the hypothesis that this approach yields less mortality and morbidity than the traditional thoracotomy approach.

One hundred four primary MBTSs with polytetrafluoroethylene grafts were constructed in patients from January 1988 through December 1992. Fifty-two shunts were constructed by thoracotomy approach and 52 by sternotomy approach. Fifteen of the thoracotomy patients were less than one month of age (8 less than 7 days), while 36 of the sternotomy patients were less than 1 month of age (20 less than 7 days). There were 10 shunt failures and 3 hospital deaths in the thoracotomy group and 4 shunt failures with 6 hospital deaths in the sternotomy group. The overall hospital mortality rate for the group was 8.7% (9 of 104). The operative route was not a significant predictor of hospital mortality (P = .30). However, there was a significant difference between the two operative approaches in shunt failure, with shunts that were created by thoracotomy four times more likely to fail than those created by the sternotomy route (odds ratio, OR, 3.88; 95% CI, 1.01 to 15.03; P = .049). The side of the shunt was also a significant predictor of failure with left-side MBTSs foru times more prone to failure (OR, 4.02; 95% CI, 1.19 to 15.25; P = .025).

The sternotomy route is technically less challenging and is associated with fewer shunt failures than the classic thoracotomy approach. The potential theoretical disadvantages of this method for future sternal reentry for subsequent procedures was not apparent but requires prospective analysis.