when your heart isn't pumping hard enough
when your heart isn't able to pump blood normally. When you have CHF there isn't enough blood flow to supply your body's organs with oxygen and nutrients. "Heart failure" doesn't mean that your heart stops beating, but that your heart isn't working properly.
therapy that involves putting a small device into your heart, to manage heart failure symptoms. It helps your heart work by sending tiny electrical impulses to your heart muscle. This may help your heart pump blood through your body.
open heart surgery
heart disease, disease of the blood vessels that bring blood to your heart
a build-up of plaque in your coronary arteries that occurs over time