Abstract
Objective
Infants born with multilevel left heart obstructive lesions (Shone’s complex), especially with mitral valve stenosis (MS), often require multiple surgeries and have a guarded prognosis. We aim to describe the characteristics of this cohort, with emphasis on echocardiographic and hemodynamic features associated with poor outcomes after biventricular repair.
Methods
Retrospective study of infants with Shone’s complex and MS between January 2016 – January 2021, who underwent biventricular surgical repair. Demographic data, cardiac catheterization and surgical reports were collected and longitudinal echocardiograms were re-analyzed. Poor outcomes were defined as death, heart transplantation or chronic mechanical ventilation.
Results
The cohort consisted of 12 patients, 8/12 with prenatal diagnosis, 11/12 male, 8/12 underwent cardiac catheterization and 7/12 had poor outcomes (5 deaths, 1 heart transplant, 1 chronic mechanical ventilation). Prenatal left to right foraminal flow (1/8) and retrograde flow in the distal aortic arch (3/8) were associated with poor outcome. Presence of a ventricular septal defect (5/12), more than mild residual mitral stenosis (5/12) or left ventricular outflow tract obstruction (3/8), and persistent pulmonary hypertension after repair (7/12) were also associated with poor outcomes. The prenatal and early postnatal size of the left heart structures and their growth were not associated with patient outcome.
Conclusion
Predictors of poor outcome in infants with multilevel left heart obstruction are related to the functional inability of the left heart to accept venous return and not to the size of the left heart structures. These findings may help family counselling and inform surgical management in the future.