Heart failure occurs when the heart is not strong enough to fill up with blood and then pump the blood out to the rest of the body. This condition is thought to affect over 20 million people world-wide including over 5 million in the United States alone. Unfortunately, there are usually few warning signs indicating imminent heart failure.
Cardiac Fibrosis and Heart Failure
Scientists at the National Institutes of Health (NIH) recently published research regarding a protein called galectin-3 which is associated with cardiac fibrosis. This protein can predict which people are at increased risk of severe cardiac failure. Cardiac fibrosis occurs when scar tissue replaces heart tissue. A certain amount of cardiac fibrosis seems to occur with normal aging; however, how much of this fibrosis is normal in healthy, elderly people with normal blood pressure is unknown. Increased cardiac fibrosis is commonly associated with increased blood pressure and as a result of such conditions as scleroderma and sarcoidosis. It can also be a result of radiation and certain drugs, viral myocarditis, or some inherited genetic mutations.
What is Galectin-3 and Why is it Important?
Galectin-3 is a mid-size protein within a group of 15 proteins called galectins. Galectins have been found to play a significant regulatory role in immunologic responses, inflammation and cancer. Galectin-3 is widely found in tissues and in epithelial cells, inflammatory cells, dendritic cells and fibroblasts. In 2010, Galectin-3 became a FDA-cleared blood test.
NIH researchers found that in research based on the Framingham Heart Study that the people with the highest levels of galectin-3 had an annual rate of heart failure of 12 per 1000 people compared to 3 per 1000 people for those with the lowest levels of galactin-3. Additionally, according to galectin-3.com, currently 2 out of 3 hospitalized patients admitted due to heart failure have galectin-3 mediated heart failure. These patients rapidly lose cardiac function and are at an increased risk of hospitalization and death.
So I Have High Levels of Galectin-3, Now what?
The point of getting a blood test for Galectin-3 is high levels of the protein will tell the physician the patient requires more aggressive management in order to prevent death. There will need to be closer patient monitoring by the physician including more frequent outpatient visits at much closer intervals than someone with low levels of galectin-3 would have. Additionally, since patients with high levels of galectin-3 are at high risk of re-hospitalization, thorough discharge planning with the goal of preventing re-admission to the hospital will be a priority.
Though the risk of death from galectin-3 mediated heart failure is significant, death is not a foregone conclusion as there are now advanced heart failure treatments. Patients with high levels of galectin-3 would be closely looked at for suitability for one or more of these treatments. These treatments range from cardiac resynchronization therapy to ventricular assist devices to cardiac transplantation.