Results of 546 Blalock-Taussig shunts performed in 478 patients

Abstract

Between 1983 and 1995, 546 Blalock-Taussig shunt procedures were performed in 472 patients: 128 (23-0%) were classical shunts, 90 of them on the same side as to the aortic arch, and 418 (77.0%) were modified shunts, 182 on the same side of the arch. At the time of surgery, 78 patients were aged below one week, 270 from one week to 12 months, and 198 patients were over one year of age. The mean pre-operative arterial saturation (71.7%± 16.5%) was significantly increased to 83%±17.9% immediately after the procedure (p=0.017). The overall hospital mortality rate was 2.9% (16/546), with rates of 2.3% (3/128) for the classical, and 3.1% (13/418) for the modified shunts (p= not significant). The rate was significantly higher, however, for classical shunts when the pulmonary arterial diameter was less than 4 mm (15.4% versus zero; p=0.047), though this relationship was reversed for modified shunts (zero versus 3-6%; p=0.338). Early mortality was significantly influenced by the age at surgery, 5/78 (6.4%) in patients aged below 1 week, 3.7% between 1 week and 1 year, and 0.5% over 1 year (p=0.019). Early mortality was also significantly increased in patients weighing 3kg or less, 8/156 (5.1%), versus 3/303 (1.0%), p=O.O37. Overall, 51 shunts failed (9.3%), 10 early and 41 late. Early failure was significantly increased in patients weighing 3kg or less, 8/156 (5.1%) versus 3/303 (1.0%), p=0.0l6. The overall early failure rate was 1.4% (3/215) when heparin was administered intra-operatively and for 48 hours postoperatively, in contrast to an early failure rate of 3.4% (7/203) when heparin was not used (p = 0.294). Overall rates of failure during follow-up were 9-1% (17/188) in heparinized patients versusl3-6% (24/177), (p=0.173) in non-heparinized patients. Failure of classical shunts was 10.2% (13/128), compared with 6.7% (28/418) for modified shunts (p=0.195). Failure was more common overall if the pulmonary arterial diameter was less than 4 mm, 14.7% (9/61), as opposed to 8.7% (26/300) when the diameter was 4 mm or greater, (p=0.l44). Administration of aspirin during follow-up after the modified shunt procedure reduced failure from 11 % (18/163) to 6.7% (10/150), p=0.176. Classical or modified Blalock-Taussig shunts, either on the same side or opposite to the aortic arch, can be performed on patients of any age with minimum postoperative complications and low operative mortality. The use of intra-and post-operative heparin appears to reduce the overall rate of failure, and the administration of aspirin during follow-up appears to reduce failure of modified Blalock-Taussig shunts.

Prevention and Treatment of Thrombosis in Pediatric and Congenital Heart Disease

“…In the Al Jubair et al 71 retrospective review, patients who received heparin intraoperatively and for 48 hours after surgery had a rate of early shunt failure of 1.4% compared with 3.4% in patients who did not receive heparin (P=0.29). It is worth noting that the use of early postoperative heparin in neonates who often have transthoracic intracardiac lines is not without risk.…”

“…Shunt thrombosis in infants has been reported to be 8% to 12% in different series and is usually life-threatening unless quickly resolved. 71,72 In addition, the placement of mechanical heart valves in children requires long-term oral anticoagulation equaling considerable patient-years. [73][74][75] Likewise, many patients with single-ventricle palliation or a history of vascular thrombosis require long-term oral anticoagulation.…”

“…241,242 Thrombosis is a significant cause of or contributor to polytetrafluoroethylene systemic to pulmonary shunt failure both in the immediate postoperative period and between phased palliation or corrective operations. 71,[242][243][244] Risk of shunt occlusion is associated with but not limited to conditions that cause intravascular volume depletion, persistently draining pleural effusions, or infection. Partial shunt occlusion commonly manifests as the inability to correct hypoxemia with increasing inspired oxygen delivery.…”

“…241,242 Al Jubair et al 71 reported their nonblinded retrospective findings of a large cohort of shunt-palliated cyanotic heart disease patients. The study group included patients with either classic (native arterial) or polytetrafluoroethylene systemic to pulmonary shunts.…”

“…In the same retrospective series noted above, patients receiving low-dose aspirin experienced a 6.7% rate of shunt failure compared with 11% in those who did not receive aspirin (P=0.18). 71 Recently, the results of a large multicenter observational trial in which infants palliated with aortopulmonary shunts who were prospectively monitored for clinical outcome demonstrated that those receiving low-dose aspirin were found to have a reduced risk of shunt thrombosis (P=0.008) and death compared with those infants not receiving aspirin. 72 The antiplatelet effect of other pharmacological agents has contributed favorably to outcome in various adult cardiovascular diseases.…”