How does nitroglycerin treat congestive heart failure?

Congestive heart failure occurs when your heart cannot do its job of pumping enough blood to the rest of your body. Nitroglycerin can help the heart do this by opening up the coronary arteries, allowing oxygen-rich blood to flow with less resistance. More oxygen to the heart muscle helps it to work more efficiently. Nitroglycerine also helps to open up the blood vessels in the rest of your body, reducing the pressure of the blood as it enters your heart and reducing the work it has to do to pump blood.