Abstract 18055: Induced Growth of Hypoplastic Cardiac Structures to Facilitate Repair of Congenital Defects
Introduction: Congenital heart defects (CHD) may include hypoplastic valves, ventricles and vessels which complicate repairs. Our hypotheses were that hypoplastic structures are developmental rather than primarily genetic in origin and the correct biomechanical signal would induce catch up growth. Our corollary hypothesis was that the growth signal is provided by flow, not pressure. First stage operations, therefore, were designed to increase flow and induce growth. Once growth was sufficient, a second operation would often complete the repair. We report our results using flow induced growth of hypoplastic structures to facilitate repair in 3 types of CHD.
Methods: Three groups of CHD patients with associated hypoplastic structures: unbalanced atrioventricular canal defects (UAVC); pulmonary atresia with intact ventricular septum (PAIVS); and coarctation of the aorta (CoA) were reviewed. Operations increased flow through the hypoplastic structures, such as creating restrictive septal defects to increase flow through the hypoplastic AV valves and ventricles (UAVC, PAIVS) or relieving obstruction (CoA) to enhance aortic valve and arch flow.
Results: On follow up, virtually all (85/90) hypoplastic structures reached normal size and the rest had nearly comparable growth (Table).
Conclusions: 1) Operations designed to increase flow through hypoplastic structures reliably induced catch up growth of UAVC, PAIVS and CoA lesions.
2) The growth response supported underdevelopment as the cause of hypoplasia and flow as the growth signal to reverse it.
3) Growth induction allowed two ventricle repairs in UAVC and PAIVS patients and avoided extended arch repairs in CoA; all with decreased operative risk.
4) Following catch up growth of the hypoplastic lesions, the outlook improved to that of patients with balanced AVCs, normal sized RVs in pulmonary atresia and well repaired CoA.
5) Once normal size was reached growth continued, producing a durable result.
Author Disclosures: D.F. Labuz: None. L.A. Pyles: None. J.A. Berry: None. J.E. Foker: None.
- © 2015 by American Heart Association, Inc.