ACE and heart failure: 3,5,6 Chronic RAS is often asymptomatic and discovered incidentally. It may be suspected when serum creatinine rises after the initiation of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs), in cases of resistant or sudden-onset hypertension, progressive CKD, or recurrent heart failure. 1,5 Acute RAS is less common, usually resulting from embolism, dissection, or plaque rupture. 7) Symptoms may range from flank pain, AKI, and flash pulmonary edema to nonspecific findings such as fever or hematuria, often delaying diagnosis. 7,8