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.