How a Heart Fails

When a person goes from a weak heart to heart failure, what happens in that transition? Finding an answer may help slow down the process or perhaps even reverse it.

Recently scientists identified a protein, called RBFox2 that appears to be important in heart health. The protein helps to regulate a process important in the maintenance of muscles.

Researchers noticed very low levels of RBFox2 in the heart of mice suffering a condition similar to heart failure. When they genetically engineered mice lacking this protein, the mice developed symptoms of heart failure. Both cases suggest there's a connection between the levels of this protein and heart muscle decline.

When the heart first weakens, it compensates by expanding to work harder and blood pressure rises to increase blood flow to the heart. As the heart continues to weaken, people enter the decompensatory phase and face fatigue and shortness of breath. This is where RBFox2 levels really decline so that instead of repairing which the heart can do, it weakens further. Researchers found that lower levels of the protein leads to changes in the way genes are used that resemble heart failure.

Just why this happens we don't yet know. We also don't know if it's possible to raise RBFox2 levels and if so whether that would slow heart decline. About half of people diagnosed with heart failure die within five years.

Even though there are medicines to help with symptoms, they don't actually make the heart stronger. In the end only a heart transplant can offer a cure but that's not an option for most people suffering heart disease since they're usually older. Finding a way to treat this disease would offer hope to millions.