Nitrate and Hypertension in Heart Transplanted Patients

Background: Cyclosporine represents a milestone in immunosuppression after organ transplantation. Its use, however, comes at the cost of significant side effects, such as arterial hypertension. Our aim was to investigate the effect of acute administration of nitroglycerin in heart-transplanted patients with cyclosporine-induced hypertension. Methods: We included 18 hypertensive patients (HT) scheduled for elective cardiac catheterization after heart transplantation and treated with cyclosporine, as well as 6-matched HT. Simultaneous measurements of BP in the aorta and pulmonary artery before and after administration of nitroglycerin were done. Results: After injection of 50μg and 100μg nitroglycerin a significant BP decrease was observed both in heart-transplanted patients (sBP p=0.0001; dBP p=0.0001) and in controls (sBP p=0.006; dBP p=0.05). This reduction was more pronounced in heart-transplanted patients (sBP p=0.022; dBP 0.018 for group comparison). 8±3 minutes after the last nitrate infusion BP remained significantly reduced vs baseline in heart-transplanted patients (p\<0.001) while it comes back to baseline in controls. The reduction in sBP (p=0.04 after 50μg nitroglycerin; p=0.05 after 100μg nitroglycerin) but not dBP correlated to cyclosporinemia. Conclusions: This study indicates that nitroglycerin reduces sBP in heart-transplanted patients with cyclosporine-induced hypertension. Further studies are needed to evaluate the long-term effect of nitrates in these patients.