Frequency of urination and heart failure

In the earlier stages of heart failure, some people need to urinate more frequently during the night than during the day. This happens because during the day, fluid and blood can pool in your legs while you are standing, resulting in less blood in the circulation and, as a result, less blood flow to the kidneys.

At night when you lie down, blood and fluid in your legs reenter the circulation and therefore increase the blood flow to your kidneys and the amount of urine produced.

If your heart failure gets worse, your kidneys receive less and less blood, both during the day and at night. As a result, the kidneys produce less urine. If you are urinating infrequently or not at all, tell your doctor right away because it may mean that the amount of blood your heart is pumping is critically low.