Interest of Remote Ischemic Preconditioning for Prevention of Contrast Medium-induced Nephropathy in High Risk Patients

Study design :

Prospective, single-center, randomized, controlled, single-blind, with RIPC procedure (Pre-CI) versus "SHAM" ischemic preconditioning (SHAM Pre -CI) (control). This test will follow the CONSORT Statement (http://www.consort-statement.org/).

This is a randomized, controlled, single-blind trial, assessing the incidence of NPCI (after a CTA ) between two group of patients, one receiving RIPC procedure and the other group receiving a "SHAM" RIPC (control group).

RIPC is accomplished by performing 4 cycles of alternating 5-minute inflation and 5-minute deflation of a standard upper-arm blood pressure cuff, to induce transient and repetitive arm ischemia and reperfusion.

RIPC will be started just before the CTA, and the time between the last inflation cycle and the beginning of the CTA will be less than 45 minutes. The "SHAM" RIPC will be carried out with the same number of cycles that the RIPC but cuff will be inflated to the diastolic pressure of the subject and the cuff will be deflated to10 mmHg in order to maintain a non- ischemic compression (blind patient protocol).

Main objective :

To assess the efficacy of remote ischemic preconditioning (RIPC) in preventing contrast-induced nephropathy (NPCI) after injected CT scanner in patients at high risk of NPCI.

Secondary objectives :

• To assess the effects of RIPC on a second marker of renal failure (Cystatin C ) ;
• To determine the pathophysiological mechanisms involved in the RIPC (role of oxidative stress ; for the first 40 patients) ;
• To assess the effect of RIPC on renal function after a second injection of contrast-medium during coronary angiography performed 2 to 4 days after the injected CTA ;
• To assess the tolerance of RIPC procedure ;
• To assess the impact on mortality at 6 months.

Inclusion criteria

• Age greater than 18 years, no upper age limit ;
• Patient which may hospitalized for a medical check-up before a percutaneous aortic valve implantation (CTA and coronarography);
• Patient at risk for NPCI defined by a Mehran risk classification system ≥11 (Annexe 2) ;
• Willing to provide free and informed written consent

Exclusion criteria

• Pathology of the upper-limbs limiting the use of the cuff (bilateral amputation, arteriovenous fistula);
• Critical renal disease requiring hemodialysis ;
• Person who is not affiliated to a health care system insurance
• Inability to understand the instructions of the study;
• Absolute contraindication to of iodinated contrast medium injection (anaphylactic shock history to contrast media, especially Xenetix, clearance (MDRD) less than 30mL/min/1.73m2) ;
• Pregnancy
• Simultaneous participation in other protocol;
• Person with legal protection, person deprived of liberty.