title: High energy phosphate depletion in leaflet matrix cells during processing of cryopreserved cardiac valves.
abstract: Preimplantation preparation of cardiac valves includes three major steps: (1) harvesting with accompanying ischemia (warm time from cessation of donor heart beat), (2) antibiotic disinfection, and (3) controlled-rate cryopreservation. To define the interdependent injury effects of these manipulations on leaflet matrix cells and specifically the potential for prolonged harvest-related ischemia to predispose greater injury by the subsequent steps, 96 semilunar valves were harvested from pigs in a manner analogous to human heart valve retrievals and randomly allocated to study groups as follows: 48 control valves were exposed to increasing harvested-related ischemic times, (2, 6, 12, 24 hr) and immersed in liquid nitrogen to arrest metabolic activity (i.e., prior to cryopreservation) and conclude the ischemia; another 48 were similarly harvested, subjected to identical ischemic times, then disinfected in 4 degrees C RPMI medium with standard antibiotics for 24 hr and dimethylsulfoxide cryopreserved at -1 degrees C/min to -170 degrees C (i.e., formal cryopreservation protocol). At thawing, each valve was extracted in 12% trichloroacetic acid and assayed by high performance liquid chromatography for components of the adenine nucleotide pool including ATP, lower energy nucleotides (total adenine nucleotides, [TAN] = [ATP] + [ADP] + [AMP]), adenosine, and the diffusible purines. Results are reported as nanomoles metabolite/milligram of leaflet cell protein (Lowry) and reflect a maintenance of total high energy phosphates in the control groups (5.41 +/- 0.29 nmole TAN at 2 hr; 8.34 +/- 0.67 nmole TAN at 24 hr), which fell significantly in all cryopreserved groups (1.27 +/- 0.33 nmole TAN at 2 hr; 0.34 +/- 0.22 nmole TAN at 24 hr).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Surgery, Medical College of Virginia, Richmond.
authors.forename: R H
authors.initials: RH
authors.lastname: Messier
authors.forename: P W
authors.initials: PW
authors.lastname: Domkowski
authors.forename: H M
authors.initials: HM
authors.lastname: Aly
authors.forename: A S
authors.initials: AS
authors.lastname: Abd-Elfattah
authors.forename: D G
authors.initials: DG
authors.lastname: Crescenzo
authors.forename: R B
authors.initials: RB
authors.lastname: Wallace
authors.forename: R A
authors.initials: RA
authors.lastname: Hopkins
mesh_terms: D000227:Adenine Nucleotides / Q000378:metabolism; D000244:Adenosine Diphosphate / Q000172:deficiency*; D000249:Adenosine Monophosphate / Q000172:deficiency*; D000255:Adenosine Triphosphate / Q000172:deficiency*; D000818:Animals; D015925:Cryopreservation; D004058:Diffusion; D005260:Female; D006351:Heart Valves / Q000166:cytology / Q000378:metabolism*; D009243:NAD / Q000378:metabolism; D011687:Purines; D013048:Specimen Handling; D013552:Swine
chemical_list: D000227:Adenine Nucleotides; D011687:Purines; D009243:NAD; D000249:Adenosine Monophosphate; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate