Joseph A. Hill, M.D., Ph.D. Answers Questions On: Heart Failure and Heart Regeneration

Heart failure is a huge and rapidly expanding problem around the world, and its prevalence is exploding for three main reasons.

The first is that the likelihood of dying from a heart attack has dropped dramatically in recent years. In fact, the likelihood of dying from heart disease overall has decreased 60 percent in the last 50 years, thanks to the hard work of many, many investigators and clinicians.

So we’ve had enormous successes in keeping people alive, but now many are living with damaged hearts that are more likely to fail over time.

Another cause for the increase in heart failure is that people are living longer, which increases the risk that their hearts will start to fail.

The third big reason heart failure is on the rise is the epidemic of obesity, which has really overtaken our society in the past 20 years, particularly in disadvantaged communities.

Although it’s not yet ready for use in patients, heart tissue regeneration has the potential for treating people with damaged hearts – particularly those with heart failure. Research being conducted in this area here at UT Southwestern is critical to advancing cardiac care.

Heart cells divide during fetal development, but after birth they might divide just once more before they exit the cell cycle and stop forever. Like brain cells (neurons), these cells are said to be post-mitotic.

Because heart cells don’t regenerate on their own, the ones we’re born with have to last our whole lives. That means if you have a heart attack that kills 20 percent of those cells, the remaining 80 percent have to carry the additional load forever.

One research focus is aimed at finding out how we can tell heart cells to re-enter the cell cycle and start dividing again.

Another research area is the stem cells that exist in tiny pockets of the heart and are, in fact, capable of regenerating and reproducing. The idea is to identify those little niches, harvest the stem cells, grow them up, and put them back in the heart.

Researchers also are looking at taking stem cells from elsewhere in the body (such as the bone marrow), transplanting them into the heart, and using drugs and blood products to make them become heart cells.

An additional area of research involves fibroblasts, the non-muscle cells that essentially just fill in the spaces of the heart. Investigators are working to figure out how to tell those fibroblasts to turn into heart-muscle cells like their neighbors.