Sleeping with a low heart rate may jeopardize heart function, brain function and kidney function. 1. Heart function: sleeping with a low heart rate can easily affect the heart function, bring chest tightness and shortness of breath, dizziness and swelling and other discomforts, and affect the blood supply of the heart to bring angina symptoms. 2. Brain function: Sleeping with a low heart rate can easily affect the normal functioning of the brain, and patients will have symptoms such as weakness, blackness, unsteadiness, insomnia, falling in the middle of the night, and even sudden fainting and coma. 3. Kidney function: Sleeping with a low heart rate may also lead to insufficient blood supply to the kidneys, low urine, affecting the normal metabolism of the body, resulting in swelling. Sleeping with a low heart rate may also be a normal phenomenon, if you sleep with a seriously low heart rate, you need to go to the regular hospital in time.