Effects Of Angiotensin-converting Enzyme Inhibitors Or Angiotensin ? Receptor Blockers On Patients With Hypertension And Normal Renal Function Before And After Exposure To Contrast Medium

Background and Objective:Contrast medium induced nephropathy(CIN)is defined as an impairment in renal function(an increase in serum creatinine by>25%or 0.5 mg/dL[44.2?mol/L])occurring within 3 days after the intravascular administration of contrast media and the absence of an alternative cause.The influence of angiotensin-converting enzyme inhibitors(ACEIs)and angiotensin ? receptor blockers(ARBs)on contrast-induced renal injury is controversial.Some studies suggested that ACEIs or ARBs was renoprotection while some has the opposite statement that the RAS blocker was one risk factor of CIN.Nevertheless,it is a common practice in some centers to stop these drugs before coronarography.The objection of our study is to find whether renal function was affected by ACEIs or ARBs in patients with hypertension and normal renal function after exposure to contrast medium(CM).Methods:Two hundred and eithty-five patients with hypertension and normal renal function were enrolled before the examine which need to take CM,such as renal or coronary CTA or Adrenal enhanced CT.They were randomly assigned to treatment group(n=129)and control group(n=156).In the treatment group,the patients received ACEIs or ARBs with conventional dose for 3 days before and after the procedure.We record the baseline clinical,biochemical,and procedural characteristics before the examine,and measured the serum creatinine(Scr),blood urea nitrogen(BUN),cystatin C(Cys C),estimated glomerular filatration rate(eGFR)at baseline and 24h and 72h after exposure to CM.The eGFR were calculated by the Modified Diet in Renal Disease study(MDRD)formula.The incidence of CIN and the changes of Scr,BUN,Cys C,eGFR at baseline and 24h and 72h after the exposure to CM between the two groups were analyzed and compared,besides,the changes of renal function were also assessed according to safe dose range of CM in two groups divided into low-dose group(<70 ml),medium-dose group(70 ml?140 ml)and high-dose group(>140ml).Results:Patients were matched with no significant differences at baseline in all measured parameters between treatment group and control group.In the comparison between the two groups,there were no significant differences in Scr,BUN,Cys C and eGFR before and after exposure to CM.The incidence of CIN in treatment group was 1.6%,which was lower than 3.2%in the control group,but no significant difference between them(P=0.61).In the comparison within the group,there were no significant differences in Scr,Cys C and eGFR before and after exposure to CM in the two groups,but the BUN in the treatment group significantly decreased from the baseline(5.53±1.37)?mol/L to(5.09±1.21)?mol/L in 24h and(5.18±1.25)in 72h after the examine(P<0.01)and the BUN in the control group significantly decreased from(5.89±3.83)?mol/L to(4.83±1.30)?mol/L in 24h and(5.01±1.33)in 72h(P?0.01).Besides,compared with the baseline,the eGFR of control group decreased slightly and Cys C tend to increase in the 24h after the procedure while the eGFR of treatment group had a rising tendency.At last,according to safe dose range of CM,the differences of renal function were not statistically significant in the two groups divided into different groups.Conclusions:Using ACEIs or ARBs to treat patients with hypertension and normal renal function before exposure to CM is safe,and may have the potential protective effect on the renal function.There is no need to discontinue this treatment prior to the procedure.