Early failure of the Shelhigh pulmonary valve conduit in infants.
BACKGROUND
The ideal valved conduit for right-sided (pulmonary) reconstruction in infants and children remains elusive. Desired characteristics include availability, ease of implantation, and longevity. Cryopreserved homografts are most commonly used, but availability of small sizes and limited durability remain problematic. The Shelhigh porcine-valved conduit (SPVC) with its No-React anticalcification properties was developed as a potential alternative to homografts.


METHODS
During a 10-month period, 8 patients underwent seven successful SPVC implantations. Median age was 9.5 days. Six conduits were less than 12 mm in diameter (range, 9 to 19 mm).


RESULTS
The early and late survival rates were 100%. During a mean follow-up of 18 months, five conduits were replaced at 6, 10, 12, 12, and 13 months for severe obstruction. Actuarial conduit failure at 12 months was 72%. Explanted SPVCs demonstrated marked pseudointimal peel formation along the original intima with an intense granulomatous inflammatory reaction. The intimal reaction was severely fibrogenic, but calcification was not present. For comparison, we retrospectively reviewed the cases of 23 infants receiving cryopreserved homografts during an overlapping period. Twelve patients, 6 of them neonates, were less than 90 days old. Mean homograft size was 13 mm (range, 8 to 15 mm), with nine less than 13 mm. During a mean follow-up of 26 months, six conduits were replaced at 7, 12, 12, 16, 20, and 35 months (sizes 13, 17, 14, 12, 10, and 12 mm, respectively). Only three of nine homografts less than 13 mm in size were replaced during a mean follow-up of 12 months. The overall homograft replacement rate was 17% at 22 months (p = 0.005) compared with the SPVC).


CONCLUSIONS
Although the SPVC appears to resist calcification, a marked foreign-body type of reaction results in pseudointimal peel formation and early conduit stenosis. In its present configuration, the SPVC in not a suitable valved conduit for use in infants. Although not ideal, the cryopreserved homograft has superior longevity to the SPVC.
Pearl
Jeffrey M
JM
Department of Pediatric Cardiothoracic Surgery, Cincinnati Children's Hospital Medical Center, Ohio 45229, USA. pearj0@chmcc.org
Cooper
David S
DS
Bove
Kevin E
KE
Manning
Peter B
PB
D001705:Bioprosthesis; D015925:Cryopreservation; D005500:Follow-Up Studies; D006330:Heart Defects, Congenital / Q000601:surgery*; D006350:Heart Valve Prosthesis; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D011475:Prosthesis Failure; D011664:Pulmonary Valve / Q000637:transplantation*; D012189:Retrospective Studies; D013997:Time Factors