Effect of warfarin on calcification of spontaneously degenerated porcine bioprosthetic valves.
Synthesis of a calcium-binding amino acid, gamma-carboxyglutamic acid, is a vitamin K-dependent enzymatic process. Warfarin inhibits gamma-carboxyglutamic acid synthesis and, therefore, might diminish the calcification of porcine bioprosthetic valves. To evaluate this, we studied 40 porcine bioprosthetic valves removed because of spontaneous degeneration; 17 patients were treated with warfarin (prothrombin time greater than or equal to 1.5 control) and 23 were untreated. Gross visualization of calcification corresponded closely to x-ray visualization of calcification in explanted valves. No grossly visible calcification or only a single localized nodule was shown in 11 of 17 valves (65%) in treated patients and in only five of 23 valves (22%) in untreated patients (p less than 0.02). Histologic examination showed no calcium or only fine specks of calcium in nine of 13 valves (69%) among warfarin-treated patients and three of 19 valves (16%) from untreated patients. Warfarin, therefore, administered in usual clinical doses, appeared to diminish calcification in spontaneously degenerated porcine bioprosthetic valves.
Stein
P D
PD
Riddle
J M
JM
Kemp
S R
SR
Lee
M W
MW
Lewis
J W
JW
Magilligan
D J
DJ
D015055:1-Carboxyglutamic Acid / Q000096:biosynthesis; D000328:Adult; D000368:Aged; D001021:Aortic Valve / Q000601:surgery; D001705:Bioprosthesis; D002114:Calcinosis / Q000378:metabolism / Q000473:pathology* / Q000517:prevention & control; D019735:Carbon-Carbon Ligases; D005260:Female; D005971:Glutamates / Q000378:metabolism; D018698:Glutamic Acid; D006350:Heart Valve Prosthesis; D006801:Humans; D008025:Ligases / Q000502:physiology; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery; D014859:Warfarin / Q000494:pharmacology / Q000627:therapeutic use*
D005971:Glutamates; D018698:Glutamic Acid; D015055:1-Carboxyglutamic Acid; D014859:Warfarin; D008025:Ligases; D019735:Carbon-Carbon Ligases; C020660:glutamyl carboxylase