Heart failure occurs when disease, injury, or years of wear and tear interfere with the heart's ability to pump as effectively and efficiently as it should. When that happens, a cascade of physiological changes is set in motion. The end result is that many body parts don't get the blood flow that they need.
Although the term "heart failure" conjures up the catastrophe of a suddenly lifeless heart, the condition is better described as a gradual decline in the heart's ability to pump.
Think if it this way: Imagine your heart as the central warehouse of a nationwide delivery system. The trucking fleet is your blood, ferrying vital supplies (oxygen and nutrients) to all corners of your body and picking up waste. Your arteries and veins are superhighways and secondary roads connecting cities and towns (cells and tissues) along the way. When the system is operating at prime efficiency, a steady stream of cargo-laden vehicles leaves the central hub at a rapid clip every day. Once their freight is delivered, they pick up the next load and return to the central warehouse.
If the warehouse falters, freight-filled trucks jam the cargo bays. Others are stranded in remote locations, unable to make deliveries or pick-ups. Customers along the routes struggle to survive without fresh supplies.
Once a slow but sure death sentence, heart failure for many people is now a chronic condition that can be coped with thanks to advances in medications, the development of heart-assisting devices, and the possibility of heart transplants.