Patients at moderate and high risk for contrast induced nephropathy (CIN) should receive sufficient hydration before application of contrast to prevent CIN, but hydration could obviously increase the preload for congestive heart failure (CHF) patients. Isosorbide Dinitrate could reduce cardiac preload and afterload by expanding vein and artery.so adequate hydration therapy combined with intravenous infusion of isosorbide dinitrate could better prevent contrast-induced nephropathy theoretically.This prospective, randomized, double-blind, comparative clinical trial randomly selected 264 patients with estimated glomerular filtration rate, (eGFR) <60 ml/min per 1.73 m2 and CHF undergoing coronary angiography to receive either the convention hydration (n=200) or the hydration therapy combined with intravenous infusion of isosorbide dinitrate(n=200).

Investigators enroll 400 patients from February 2016 to February 2017, the principal inclusion criterion included CHF: left ventricular eject fraction (LVEF) <= 50%; moderate to severe chronic kidney disease(CKD) was diagnosed as an eGFR 15 to 59 mL/min per 1.73 m2, calculated via the abbreviated Modification of Diet in Renal Disease (MDRD) study equation from SCr obtained within 72 hours of enrollment, patients were scheduled to undergo diagnostic cardiac angiography or percutaneous coronary interventions. We randomly assigned eligible patients in a 1:1 ratio to either the hydration therapy combined with intravenous infusion of isosorbide dinitrate or a standard hydration administration protocol. hydration therapy combined with intravenous infusion of isosorbide dinitrate refer to give intravenous infusion of isosorbide dinitrate on the basis of fully hydration to reduce cardiac preload.afterload and increase the the tolerance degreen of hydration in chronic heart failure patients. both study groups received intravenous fluids for the same hydration dose. All study participants received intra-arterial Visipaque(320 mg I/ml; GE Healthcare) iso-osmolar contrast medium.

Primary end point of the study was the incidence of CIN: The median peak increase in serum creatinine concentration between day 0 (when contrast was administered) and day 7. Definition of CIN was an absolute increase in serum creatinine (SCr) >0.5 mg/dl or a relative increase >25% compared to baseline SCr. Definition of non-Q-wave myocardial infarction was a creatine kinase-myocardial band enzyme elevation 3 times the upper normal value without new Q waves on the electrocardiogram. Definition of Q-wave myocardial infarction was presence of new pathologic Q waves on an electrocardiogram in conjunction with an elevation in creatine kinase greater than 3 times the normal value. All adverse clinical events as well as study end points were monitored and adjudicated by the independent event committee. Each patient was contacted in every week after administration of the contrast, investigated if dialysis or main cardiovascular events (myocardial infarction,acute heart failure and death), and record any adverse events.

Inclusion Criteria:

1. congestive heart failure: objective evidences for decreased left ventricular eject fraction (LVEF) <= 50%;
2. moderate to severe chronic kidney disease was defined as an eGFR 15 to 59 mL/min per 1.73 m2, calculated via the abbreviated Modification of Diet in Renal Disease (MDRD) study equation from SCr obtained within 72 hours of enrollment;
3. patients were scheduled to undergo diagnostic cardiac angiography or percutaneous coronary interventions.

Exclusion Criteria:

1. hemodialysis-dependent patients;
2. complicated with severe short-term progressive disease;
3. Patients < 18 years;
4. pregnancy;
5. emergency cardiac catheterisation (eg, primary percutaneous coronary intervention for ST-segment elevation myocardial infarction);
6. exposure to radiographic contrast media within the previous 7 days;
7. acute decompensated heart failure.