Your heart has the ability change itself. In the same way your biceps muscles will grow if you lift weights, your heart muscle can also grow. Unfortunately, your heart was already set at the perfect proportions, and changes in the muscle mass of your heart aren’t necessarily a good thing.
If you have high blood pressure, scar tissue on your heart muscle from a previous heart attack or from some other cause, a valve or artery disease, your heart may need to work harder to push blood around your body. This extra work makes the heart muscle get bigger. However, it isn’t getting stronger. It’s getting weaker, the bigger it gets. Often the left ventricle (the one that has the job of pumping blood through the the body) grows inward as well as outward with the extra workload, meaning that there’s now less room for the blood that needs to get pumped out. Because there’s less room for blood, the heart has to pump more often to pump the same volume of blood around the body.
As you might expect, this makes the muscle even bigger, making the volume of blood perfused with each beat even less. You can see how this becomes a vicious cycle, resulting in aberrant conduction of electrical signals among other serious problems.
The good news is that while the heart can make itself larger, it can also make itself smaller. This changing in the heart’s structure is what is called remodeling. For those suffering from congestive heart failure, a prescription for a beta blocker, which can slow heart rate and lower blood pressure, might be all that’s needed to ease the burden on the heart, making it easier to pump. The reduction in workload will allow the muscle mass in the heart to decrease, the heart remodeling itself to adjust to the new, less strenuous demands. Just like if you stop curling the 50 pound dumbbells and switch to the 20 pounders.
With less muscle mass there’s now more room for blood in the ventricles, which means more blood is pumped per beat, allowing the heart to further reduce the number of times it beats per minute, decreasing it’s workload even more. In time this may result in a heart that is capable of pumping normal amounts of blood (as measured by ejection fraction) at a normal heart rate.
