Femoral vein homograft as Sano shunt results in improved pulmonary artery growth after Norwood operation

Abstract

ObjectiveTo evaluate differences in interstage growth of pulmonary arteries between use of polytetrafluoroethylene and femoral vein homograft as Sano shunt during stage-I Norwood palliation.MethodsA retrospective review of all patients who survived to the second stage following Norwood–Sano operation at two institutions was performed. Either polytetrafluoroethylene or the valved segment of femoral vein homograft was used for construction of the Sano shunt. The size of pulmonary arteries was compared at pre-Glenn catheterisation.ResultsA total of 48 neonates with the diagnosis of hypoplastic left heart syndrome or its variants comprised the study population. Femoral vein homograft of 5–6 mm diameter was used in 14 and polytetrafluoroethylene graft of 5 mm was used in 34 patients. The two groups were comparable in terms of preoperative demographics and age at time of pre-Glenn catheterisation (3.9±0.7 versus 3.4±0.8 months, p=0.06). Patients who received femoral vein homograft demonstrated a significantly higher pre-Glenn Nakata index [264 (130–460) versus 165 (108–234) mm2/m2, p=0.004]. The individual branch pulmonary arteries were significantly larger in the femoral vein group (right, 7.8±3.6 versus 5.0±1.2, p=0.014; left, 7.2±2.1 versus 5.6±1.9, p=0.02). There were no differences in cardiac index, Qp:Qs, ventricular end-diastolic pressure or systemic oxygen saturations.ConclusionsUtilisation of a valved segment of femoral vein homograft as right ventricle to pulmonary artery conduit during Norwood–Sano operation confers better interstage growth of the pulmonary arteries. Further studies are needed to evaluate the impact of femoral vein homograft on single ventricle function.

Impact of a Composite Valved RV-PA Graft After Stage 1 Palliation

“…We acknowledge that there are a number of technical variations on homograft use, and many centers do not use a composite RVPAS or enshroud the homograft within a constricting stent, and these differences may in part explain our negative results regarding pulmonary arterial growth. However, as suggested by other groups [11], we found that short-term postoperative hemodynamics were somewhat more favorable in the presence of a homograft, including a higher SaO 2 and a lower serum lactic acid concentration. The incidence of extracorporeal membrane oxygenation use and ICU lengths of stay were similar between the groups.…”

“…The use of a SVH [8][9][10] or FVH [11,12] as part of the S1P has been well described. However, the cumulative published experience with SVHs has been limited to single patient case reports or small case series [9,10,16].…”

“…Even in these small case series, it was suggested that time to S2P may be shorter (3 months) among patients after SVH than after a synthetic RVPAS (4 to 6 months) [10]. The use of FVH has been described in a series of 15 neonates undergoing S1P [11,12], concluding that PA growth (ie, increase in RPA and LPA z score) was higher in patients treated with a FVH than with a PTFE-only RVPAS. In contrast, a series of 100 patients treated with primarily aortic and pulmonary arterial homografts as part of S1P reported no difference in PA growth compared with a contemporaneous cohort of nonvalved RVPAS [13].…”

“…In addition to the possibility of augmenting PA growth, use of a valved RVPAS may reduce right ventricular volume loading. The use of a femoral vein homograft (FVH) as an RVPAS as part of S1P has been reported to significantly increase in branch PA size compared with the use of a PTFE-only RVPAS [11,12]. Another group described that PA growth among 100 neonates with a heterogeneous combination of valved homografts did not significantly differ from those with PTFE-only RVPAS [13].…”

Hypoplastic left heart syndrome and the allure of a valved conduit

“…5 A noticeable omission is the lack of branch pulmonary artery size data at the time of cardiac catheterization before bidirectional cavopulmonary shunt. Showing better pulmonary artery growth with a valved RV-PA conduit, as others have, 6 would certainly enhance the argument for its use. Finally, the rate of intervention on the conduit is high in comparison with current techniques of nonvalved conduit implantation.…”