No-react detoxification process: a superior anticalcification method for bioprostheses.
BACKGROUND
Glutaraldehyde pretreatment of bioprosthetic heart valves is the major pathogenic factor in their calcific degeneration. This comparative study investigates the merit of the No-React aldehyde detoxification process as an alternative modifier of xenograft tissues.


METHODS
Glutaraldehyde- and No-React-pretreated porcine aortic valve cusps were implanted subcutaneously in 6-week-old rats (n = 20). At 3, 6, and 14 weeks, randomly selected animals were sacrificed and the explants underwent mineral and morphologic analyses. Glutaraldehyde- and No-React-treated bovine pericardium and porcine aortic valve cusp were incubated in fibroblast cell culture plates. Cell viability was observed under reversed microscope at 6, 24, 48, and 96 hours. Erythrosin B dye exclusion test was used to validate percent cell death.


RESULTS
Pretreatment with No-React significantly inhibited calcification of aortic cusp subcutaneous implants throughout the 14-week period (mean tissue Ca2+ content = 1.3 +/- 0.7 micrograms/mg at 14 weeks.) Glutaraldehyde-treated cusps underwent protracted calcification (Ca2+ content = 190.6 +/- 89.5 micrograms/mg; p < 0.01). Morphologic findings correlated with mineral analyses. One-hundred percent of fibroblast cells survived in the presence of No-React-treated tissue, with a growth pattern indistinguishable from control cell culture (ie, in the presence of no tissue). The cells incubated with glutaraldehyde-treated tissue showed signs of nonviability by 6 hours, with 100% cell death by 48 hours. Dye exclusion tests validated these findings.


CONCLUSIONS
The No-React detoxification process completely abolishes the cytotoxicity of the xenograft tissue and inhibits calcific degeneration.
Abolhoda
A
A
UMDNJ-New Jersey Medical School, Department of Surgery, Newark 07103, USA.
Yu
S
S
Oyarzun
J R
JR
Allen
K R
KR
McCormick
J R
JR
Han
S
S
Kemp
F W
FW
Bogden
J D
JD
Lu
Q
Q
Gabbay
S
S
D000818:Animals; D001021:Aortic Valve; D001672:Biocompatible Materials; D001705:Bioprosthesis; D002114:Calcinosis / Q000517:prevention & control*; D002118:Calcium / Q000032:analysis; D002470:Cell Survival; D002478:Cells, Cultured; D005976:Glutaral; D006350:Heart Valve Prosthesis; D051379:Mice; D011475:Prosthesis Failure; D051381:Rats; D017207:Rats, Sprague-Dawley
D001672:Biocompatible Materials; D002118:Calcium; D005976:Glutaral