Acute effect of nitroglycerin on cyclosporine-induced hypertension after cardiac transplantation.

Abstract

Cyclosporine represents a milestone in immunosuppression following organ transplantation. Its use, however, comes at the cost of significant side effects, such as arterial hypertension which is rarely controllable by currently available anti-hypertensive drugs. The aim was to investigate the effect of acute administration of nitroglycerin in heart-transplanted patients with cyclosporine-induced hypertension. The sample included 18 cyclosporine-induced hypertensive patients (HTX group) scheduled for elective cardiac catheterization following heart transplantation, as well as 6-matched essential hypertensive patients (HT group). The blood pressure (BP) in the aorta and pulmonary artery, before and after administration of nitroglycerin, was measured simultaneously. After injection of 50 µg and 100 µg nitroglycerin, BP significantly decreased both in HTX (systolic (s) BP p = 0.0001; diastolic (d) BP p = 0.0001) and in controls (sBP p = 0.006; dBP p = 0.05). This reduction was more pronounced in HTX (sBP p = 0.022; dBP p = 0.018 for group-comparison). Following analysis of the data in relation to its individual baseline, a significantly higher reduction of the BP induced by 100 µg nitroglycerin was observed in the HTX group compared to the HT group (p = 0.02 for sBP and p = 0.03 for dBP). 8 +/- 3 minutes after the last nitrate infusion, BP remained significantly reduced compared to baseline in HTX (p <0.001), whereas it came back to baseline in controls. The reduction in sBP was correlated to cyclosporine A levels (p = 0.04 after 50µg nitroglycerin; p = 0.05 after 100 µg nitroglycerin). After application of nitroglycerin, sBP is reduced immediately in HTX with uncontrolled cyclosporine-induced hypertension. Further studies are needed to evaluate the long-term effect of nitrates in these patients.