Hydration Guided by Remote Dielectric Sensing (ReDS) System for Preventing Acute Kidney Injury in Elderly Patients With Renal Insufficiency for Coronary Angiography and Intervention

This trial is testing whether using a non-invasive device called a ReDS sensor — which measures fluid levels in the lungs — to guide hydration before and after a cardiac catheterization procedure can reduce the risk of kidney damage (contrast-induced acute kidney injury) in elderly patients who already have some kidney impairment. **You may be eligible if...** - You are 60 or older - You have unstable angina and are scheduled for coronary angiography (an X-ray procedure to look at the heart arteries), which may include a stent procedure - You have chronic kidney disease (estimated GFR below 90 ml/min) **You may NOT be eligible if...** - You have acute decompensated heart failure or cardiogenic shock (a heart emergency) - You have severe kidney failure (GFR below 30 ml/min) or malignant tumors - You have respiratory failure - You have received contrast dye within the past week - You are allergic to contrast dye Talk to your doctor to see if this trial is right for you.