Initial shunt type at the Norwood operation impacts myocardial function in hypoplastic left heart syndrome

Eur J Cardiothorac Surg. 2017 Aug 1;52(2):234-240. doi: 10.1093/ejcts/ezx102.

Abstract

Objectives: We investigated the impact of initial shunt type, a Blalock-Taussig (BT) shunt versus a right ventricle to pulmonary artery conduit (RV-PA) on myocardial function at different stages of surgical palliation in patients with hypoplastic left heart syndrome (HLHS).

Methods: A population-based cohort of 63 Finnish children with HLHS (BT n = 23, RV-PA n = 40) born between 2003 and 2010 were studied retrospectively by echocardiography prior to Stages 1, 2 and 3 palliation and 0.5-3 years after Stage 3. For comparison of systolic myocardial function, we evaluated the RV fractional area change (FAC), strain, strain rate and mechanical synchrony from the apical 4-chamber view by velocity vector imaging.

Results: There were no intergroup differences in demographics during the study period. At baseline, no intergroup differences were detected in RV systolic myocardial function. Before Stage 2, RV FAC was higher ( P = 0.03) in the RV-PA conduit group. At Stage 3, an increase in all systolic myocardial functional parameters was observed in the BT shunt group. After Stage 3, the BT shunt group had better RV systolic function. In multiple regression analysis, the shunt type and the stage of palliation had an impact on myocardial function.

Conclusions: Although patients with HLHS initially palliated with a BT shunt demonstrate lower RV FAC after Stage I, RV FAC improves after Stage 2 with better systolic performance after Stage 3 compared with those initially palliated with an RV-PA conduit.

Keywords: Blalock–Taussig shunt; Fractional area change; Hypoplastic left heart syndrome; Right ventricle to pulmonary artery conduit; Velocity vector imaging.

MeSH terms

  • Blalock-Taussig Procedure / statistics & numerical data*
  • Cardiac Catheterization
  • Child, Preschool
  • Echocardiography
  • Female
  • Heart / diagnostic imaging
  • Heart / physiopathology*
  • Humans
  • Hypoplastic Left Heart Syndrome / diagnostic imaging
  • Hypoplastic Left Heart Syndrome / epidemiology*
  • Hypoplastic Left Heart Syndrome / surgery*
  • Infant
  • Infant, Newborn
  • Male
  • Norwood Procedures / instrumentation
  • Norwood Procedures / statistics & numerical data*
  • Palliative Care
  • Retrospective Studies