Renal artery stenosis is a narrowing of arteries that carry blood to one or both of the kidneys. Most often seen in older people with atherosclerosis (hardening of the arteries), renal artery stenosis can worsen over time and often leads to hypertension (high blood pressure) and kidney damage. The body senses less blood reaching the kidneys and misinterprets that as the body having low blood pressure. This signals the release of hormones from the kidney that lead to an increase in blood pressure. Over time, renal artery stenosis can lead to kidney failure. In this study, the effects of viscous heating in renal artery stenosis under peristaltic wall motions were investigated. Renal artery stenosis usually does not cause any specific symptoms. Sometimes, the first sign of renal artery stenosis is high blood pressure that is extremely hard to control, along with worsening of previously well-controlled high blood pressure, or elevated blood pressure that affects other organs in the body.