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Two-stage biventricular rehabilitation for critical aortic stenosis with severe left ventricular dysfunction.

OBJECTIVES
Critical aortic valve stenosis (CAS) in the newborn is treated by balloon or surgical aortic valve intervention with nearly equal success, but the subset of patients with severe left ventricular (LV) dilation and dysfunction present a significant mortality risk. We describe a two-stage surgical management approach for those infants who represent an unusually high failure risk for either aortic valvotomy or conventional stage 1 single ventricle (Norwood) palliation because of severe LV dysfunction at the time of presentation.


METHODS
A two-stage surgical palliation was undertaken consisting of surgical aortic valvotomy, bilateral pulmonary artery banding and atrial septectomy (stage 1), followed by patch closure of the atrial septal defect, ligation of the ductus arteriosus and removal of the pulmonary artery bands (stage 2) with prostaglandin infusion continued between stages to maintain right ventricular contribution to systemic perfusion via the ductus arteriosus.


RESULTS
Four neonates with CAS and severely depressed LV systolic function were treated using this strategy. LV dilation resolved and systolic function improved in three patients after 2, 2 and 4 weeks, enabling stage 2. LV dysfunction did not improve in one patient who expired before conversion to biventricular circulation. Of the three who proceeded to stage 2, one infant continued to have poor biventricular diastolic function that precluded conversion, and this patient also died. The remaining two infants are now alive and well at 34 and 44 months of age. These two had the most severe LV dilation (internal dimension Z-scores of 6.9 and 7.7) and the worst systolic function (fractional shortening 4 and 10%) at presentation, and both were born prematurely (32 and 35 weeks).


CONCLUSIONS
A two-stage surgical approach may improve the likelihood of survival in selected patients with CAS presenting with severely depressed LV systolic function. Relief of LV distention may have contributed to the improvement of LV function in these infants.