Heart disease is the leading cause of death in the United States and responsible for almost 1 in 4 deaths in the country.
An adverse cardiovascular event, such as a heart attack, typically damages the cells that make up the heart muscle.
These cells are called cardiomyocytes, and losing them puts people at risk of heart failure — a condition wherein the heart cannot pump blood effectively to the rest of the body.
The scientific consensus is that adult hearts can no longer create new cardiomyocytes. This inability is why the heart cannot regenerate itself after a heart attack when huge numbers of cardiomyocytes are lost.