Clinical Outcomes after Biologic Graft Use for the Creation of Blalock-Taussig Shunt in Critically Ill Patients with Thrombophilia
Authors: Azboy Davut , Temiztürk Zeki 
Published: October 2020

Background: The modified systemic to pulmonary artery shunt (mSPS) is an effective palliative procedure in children with cyanotic congenital heart disease (CCHD) who are not suited for total correction. Early graft failure related to hereditary thrombophilic disorder is one cause of mortality. The aim of this study is to compare the clinical outcomes and rate of graft failure after mSPS in cyanotic infants with hereditary thrombophilia using bovine mesenteric venous graft (BMVG) and polytetrafluoroethylene (PTFE).
Methods: 60 cyanotic patients (28 neonates, mean age 19 ± 11.3 days; range 1 to 27) who had thrombophilic risk factors were divided into 2 groups: BMVG (n = 30) and PTFE (n = 30). Preoperative thrombophilic factors were measured for each patient. The most common thrombophilic factors were protein C and S deficiency and Factor V Leiden mutation. We also investigated D-dimer, positivity of prothrombin G20210A, factor XII and antithrombin III deficiency, and homocysteinemia in both groups. The mean age of patients was 4.6 ± 1.09 months (range 1 day to 6 months) in the BMVG group and 3.9 ± 1.02 months (range 2 days to 9 months) in the PTFE group (P = .67). mSPS procedures were performed via left thoracotomy (n = 19 in the BMVG group and n = 22 in the PTFE group) or right anterior thoracotomy (n = 3 in the BMVG group and n = 3 in the PTFE group). Median sternotomy was performed to create a central shunt in 8 neonates in the BMVG group. In the PTFE group, we performed a central shunt in 5 patients via median sternotomy. Low molecular weight heparin in combination with acetylsalicylic acid (aspirin) were administered after surgery in both groups. The patients received aspirin combined with warfarin (Coumadin) after being discharged from hospital. We performed revision surgery to observe whether any patient had a significant drop in saturation with inaudible mSPS murmur.
Results: 7 patients died early after surgery (n = 2 in the BMVG group [6.6%] and n = 5 in the PTFE group [16.5%]; P = .022). 53 patients were discharged home in good clinical condition. Early graft thromboses were observed in 2 patients in the BMVG group (6.6%) and 8 patients in the PTFE group (26.6%) (P = .001). In a case from the BMVG group, the reason for graft thrombosis was entanglement of the graft. Revision surgery was performed successfully without any complication. Cil et collegues has been reported a successful percutaneous balloon angioplasty after an acute thrombosis of BMVG previously [Cil 2010]. In another patient who had acute BMVG thrombosis, we performed transluminal graft angioplasty using successful thrombolytic administration in the catheterization laboratory. There were no complications due to graft materials such as hematoma, seroma, or infection in the BMVG group. Bleeding from the needle hole was seen in 1 patient in the BMVG group. PTFE thrombosis developed in 3 patients within 24 hours (10%). We detected total or partial PTFE graft thrombosis in 5 patients during the follow-up period (20%). Revision surgeries in 3 patients were performed immediately after diagnosis. Transluminal balloon angioplasty combined with thrombolysis was performed in infants with partial or total PTFE occlusion in 5 patients. In the PTFE group, perigraft seroma (n = 5 [16.6%)] and hematoma (n = 2 [6.6%]) were detected. We performed revision surgery because of bleeding from the needle hole in 3 patients in the PTFE group (10%) in the early period after surgery. We detected a graft infection in 1 patient (3.3%) 6 months after surgery in the PTFE group. The rate of overall complications including pseudoaneurysm, seroma formation, graft infection, or partial or total graft occlusion in the early and follow-up periods was 6.6% in the BMVG group and 53.3% in the PTFE group (P = .0001). The rate of freedom from shunt failure was 92.6% ± 2.1% and 76.2% ± 4.8% during follow-up in BMVG and PTFE groups, respectively (P = .034). The rate of shunt-related mortality was 10.7% (n = 3) in the BMVG group and 20% in the PTFE group (P = .01). Regular physical examinations, transcutaneous oxygen saturation, and echocardiographic study were performed for shunt control during follow-up. Shunt occlusion or thrombosis was not seen in the BMVG group; 5 patients in the PTFE group (20%) had shunt occlusion during follow-up (P = .001).
Conclusion: Our study shows that BMVG, as a biological material, may be used as an alternative material for creating mSPS. It decreases postoperative life-threatening complications after shunt procedures, including graft thrombosis, bleeding from the needle hole, perigraft hematoma, and seroma in patients with hereditary thrombophilia. To our knowledge, we report the first clinical comparison of the 2 grafts in our case series with thrombophilic risk factors.