When the kidneys don't work well, more stress is put on the heart. When someone has CKD, their heart needs to pump harder to get blood to the kidneys. This can lead to heart disease, the leading cause of death in the United States. Change in blood pressure is also a CKD complication that can lead to heart disease.
Relatively recent research has shown that heart failure is a significant risk factor for kidney disease. When the heart is no longer pumping efficiently it becomes congested with blood, causing pressure to build up in the main vein connected to the kidneys and leading to congestion of blood in the kidneys, too.
Urinary system and Circulatory systems work together: The urinary system cleans the blood in the circulatory system. Blood traveling back to the heart passes through the kidneys in the urinary system. The kidneys clean the blood and control the amount of salt, water, and other substances in the blood.