Lipoprotein(a) and apolipoprotein changes after cardiac transplantation

Abstract

Although lipoprotein changes after cardiac transplantation have been documented, the effects of transplantation and subsequent immunosuppressive therapy (particularly the combination of prednisone, azathioprine and cyclosporine) on apolipoprotein levels and lipoprotein(a) have not been reported. Fasting cholesterol, triglycerides, high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol, apolipoprotein A-1 and B-100 and lipoprotein(a) were evaluated in 69 consecutive patients during the waiting period before cardiac transplantation. There were 28 deaths before donor organ identification and 41 patients received a cardiac allograft. The lipoprotein levels of transplant recipients were again assayed 3 months postoperatively. Mean (± SEM) values increased for total plasma cholesterol (from 180 ± 8 to 228 ± 8 mg/dl, p ≤ 0.001), triglycerides (from 126 ± 11 to 207 ± 14 mg/dl; p ≤ 0.001), HDL cholesterol (from 39 ± 2 to 49 ± 3 mg/dl; p ≤ 0.002) and LDL cholesterol (from 119 ± 7 to 138 ± 7 mg/dl; p < 0.02). Apolipoprotein A-1 and B-100 also increased, but lipoprotein(a) decreased from 11.7 ± 1.7 to 6.8 ± 1.1 mg/dl; p ≤ 0.0001) after transplantation. Although total cholesterol, triglycerides, LDL cholesterol, apoliprotein A-1 and B-100 increased dramatically after cardiac transplantation, so did HDL cholesterol, thereby keeping the LDL HDL cholesterol ratio constant. The surprising decrease in lipoprotein(a) after cardiac transplantation suggests that metabolism of lipoprotein(a) is independent of LDL cholesterol and that immunosuppressive drugs either decrease the synthesis or increase catabolism of lipoprotein(a). © 1991.