Modified Blalock-Taussig shunt. Use of subclavian artery orifice as flow regulator in prosthetic systemic-pulmonary artery shunts.

Between April, 1975, and December, 1979, 99 modified Blalock-Taussig shunts (MBTSs) were carried out at The Hospital for Sick Children, Great Ormond Street. The operation consists of interposing between the subclavian artery and the pulmonary artery a prosthesis of greater diameter than that of the subclavian artery. The first 13 operations were performed with a prosthesis of woven Dacron. Conduits of expanded polytetrafluorethylene (PTFE) were used for 86 MBTSs, and these form the basis of this report. Forty-four (51.1%) shunts were performed in infancy, 25 in patients under the age of 1 month (29.0%). Prostheses of 4 mm were used in 34 cases, 5 mm in 14, and 6 mm in 38. There were five shunt failures (5.8%) documented at postmortem or angiocardiographic investigation. Including two late deaths for which postmortem examinations were not obtained, the overall failure rate was 8.1% (seven patients). All these patients were operated upon in infancy, four of them in the neonatal period. Although a longer follow-up is necessary to assess the validity of these shunts, the early results are encouraging. We believe we can now recommend MBTS as an alternative when the classical Blalock-Taussig shunt is considered unsuitable.