Calcium antagonists in heart transplant recipients: effects on cardiac and renal function and cyclosporine pharmacokinetics

Can J Cardiol. 1993 Jun;9(5):398-404.

Abstract

Objective: Cyclosporine increases transmembrane calcium flux in mesangial and vascular smooth muscle cells, which may explain cyclosporine-induced decreases in renal bloodflow and glomerular filtration rate. Calcium antagonists, thus, may play a role in the prevention/reversal of cyclosporine nephrotoxicity.

Design: In a single-blind, randomized, cross-over study the authors evaluated the effects of a one-week treatment with nifedipine 20 mg bid, diltiazem 120 mg bid or placebo on cardiac and renal functions of six stable heart transplant recipients treated chronically with cyclosporine.

Results: Both calcium antagonists lowered blood pressure compared with placebo, but only nifedipine increased cardiac output and, therefore, decreased total peripheral resistance significantly more than diltiazem. Nifedipine induced a significant increase in effective renal plasma flow and an insignificant increase in glomerular filtration rate, whereas diltiazem caused a reduction in these parameters. Cyclosporine pharmacokinetics were not affected by either calcium antagonist to a clinically significant extent.

Conclusions: Nifedipine and diltiazem exert distinctly different cardiac and renal hemodynamic effects in cardiac transplants, which may have clinical consequences.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cyclosporine / pharmacokinetics*
  • Cyclosporine / therapeutic use
  • Diltiazem / therapeutic use*
  • Heart Transplantation*
  • Hemodynamics / drug effects*
  • Humans
  • Hypertension / drug therapy*
  • Immunosuppression
  • Kidney / drug effects*
  • Kidney Function Tests
  • Male
  • Middle Aged
  • Nifedipine / therapeutic use*

Substances

  • Cyclosporine
  • Diltiazem
  • Nifedipine