Serum aminoterminal propeptide of type III procollagen after cardiac transplantation and the effect of rejection

The present study examines serum concentrations of the aminoterminal propeptide of type III procollagen (S-PIIINP), a marker of type III collagen synthesis, after heart transplantation, and assesses changes induced by rejection. Fourteen transplant patients were included with 12 coronary artery bypass patients serving as controls. Mild to moderate rejection was found in 44 biopsies, and severe rejection in 6. Two severe rejection incidents occurred before postoperative day 10, the remainder at postoperative days 23 to 57. S-PIIINP was elevated in transplant patients at postoperative days 1 to 7 (p ≤ 0.01), with return to baseline at postoperative day 60 (p = 0.14, n = 6). S-PIIINP remained unchanged after mild to moderate rejection, but increased 1 to 2 weeks following severe rejection occurring after postoperative day 10. S-PIIINP was elevated in bypass patients from postoperative day 2 throughout the study period of 360 days (p ≤ 0.01). Thus, type III collagen turnover after heart transplant and coronary artery bypass grafting resembles wound healing. Collagen synthesis after severe rejection is reflected by SP-IIINP approximately 2 weeks after transplant. The findings may prove to be significant concerning the prognosis of heart transplant patients.