Occlusion of the modified Blalock-Taussig shunt: unique methods of treatment and review of catheter-based intervention.

OBJECTIVE:To report unique methods of treatment and review catheter-based intervention for occluded modified Blalock-Taussig shunts (BTS). METHODS:Case reports and articles involving children undergoing catheter-based treatment for occluded modified BTS were reviewed. RESULTS:Literature review detailed 38 patients in whom occluded modified BTS were treated with 39 catheter-based interventions. Thrombolytics alone were delivered by catheter in 13 cases. Balloon angioplasty was performed in 23 cases, 5 with stent implantation. Both thrombolytic delivery and angioplasty were performed in 3 cases, 2 with stent implantation. Intervention was initially successful at re-establishing modified BTS patency in 35/39 (90%) of cases. Patency could not be established in 2 patients who then proceeded to the operating for surgical shunt revision. Two deaths occurred during the procedures. Three cases at Emory University demonstrate uncommon or unique instances of catheter-based intervention: (1) declotting of a shunt in a patient supported by extracorporeal membrane oxygenation (ECMO); (2) declotting of a shunt via a right axillary arterial approach; and (3) declotting of a shunt using a carotid arterial (ECMO) cannula for percutaneous access. CONCLUSIONS:The use of catheter-based techniques for the treatment of BTS occlusion is highly successful, and potentially avoids high-risk re-operative intervention. ECMO can provide for a stable patient during the procedure. Hopefully, with improved technology and innovative procedures, more children in the future with BTS occlusion can be served by successful percutaneous intervention.