What Is the Difference Between Left- and Right-Sided Heart Failure? October 22, 2014

We often discuss heart failure as if it is a single type of phenomenon. In reality, the two sides of the heart can fail independently of each other, and each event has its own causes and effects. So what is the difference between the two?

Understanding how the Heart Works

To see the difference between heart failure on the left and right side, it’s important to understand where the heart is located and how it works. The heart has two jobs: to collect returning, “used” blood and pump it into the lungs to be enriched with oxygen, and to take oxygen-rich blood from the lungs and pump it out to the rest of the body. The heart’s left and right sides are each responsible for one of these two crucial jobs.

Prevention and treatment of heart failure

We often think of the heart as being located in the center of the chest, but in reality the heart sits off slightly to the left side. This is the ideal position to allow it to do both its jobs. From this location, the left side of the heart is close to the top of the left lung, and this placement determines the respective jobs of the left and right ventricles of the heart.

The left ventricle is by far the larger of the two halves of the heart, because it does the difficult job of pumping blood out to the entire body. It draws the blood from the left lung where it has been filled with fresh oxygen. The pumping of this side of the heart sends the blood out to all the body’s organs and extremities, which need the oxygen to live and work.

As oxygen is depleted from the blood, it returns to the heart on the right side. The right ventricle pumps the blood back to the lungs to start the process over. Both the left and right ventricles‘ jobs are necessary for people to live—and either or both can be interrupted by heart failure.

Causes of Heart Failure

Heart failure occurs when one or both sides of the heart have difficult pumping (or difficulty relaxing between pumps). This can be caused by many things, from a blood clot or heart attack to congenital factors. However, heart failure has different effects, depending on which side it strikes.

In left-sided heart failure, the heart can no longer adequately bring in fresh blood from the lung and pump it out to the body. This causes blood to back up and pool in the left lung. Shortness of breath, heaviness in the chest and difficulty breathing are common signs of left-sided heart failure.

Right-sided heart failure often occurs in response to left-sided failure. The right ventricle becomes overworked and fails in turn. If right-sided heart failure occurs on its own, blood returning from the body becomes backed up.

Both versions of heart failure are extremely serious and need to be treated immediately. The earlier that heart failure treatment is administered, the more likely it is that the patient can survive and recover.