How can you mend a broken heart? As you might guess, I'm not going to talk about the BeeGees pop hit from the 70s, failed romance, or the latest Nicholas Spark's novel. Let's talk about heart failure. Heart disease is the leading cause of death in the United States, responsible for one in four deaths every year.[1]
One of the challenges is that current treatments for heart disease cannot fix the problem of the loss of heart tissue. Scientists have turned to stem cell research as a potential solution to this growing problem.[2]
There's good news from early results of several small clinical trials. The most successful of these trials used stem cells taken from the patient's own heart. Scientists are also investigating whether other stem cells, such as those found in fat or in bone marrow, could repair the heart after a heart attack.[3]
A heart attack is devastating. First, it can destroy as much as 25% of the muscle cells that make the heart contract. This leads to a large mass of scar tissue. The heart is forced to work harder to pump blood. To mend this heart, you need to replace the scar tissue with healthy cells, and improve the heart's ability to pump blood. That's where two other clinical trials, in Los Angeles[4] and Kentucky,[5] come in.
In these trials, stem cells were taken from a heart biopsy, grown in the lab, and returned to the diseased heart. The results? The stem cells went right to work, reducing scar tissue, and growing healthy heart muscle.[6] Every patient had some improvement, and not a single patient had a health setback.
In the Kentucky trial, the patients' hearts pumped as much as 8 percent more blood. It may not sound like much, but for one patient it meant the difference between having to stop for breath on the way to the restroom and being able to play basketball with his grandchildren.[7]
I want to point out that all the stem cells used in these clinical trials come from ethical sources: the patient's own body. No human embryos were destroyed to harvest their stem cells. My commentary today is more than a science update; it's a tribute to the amazing potential of moral medical research.
The Los Angeles and Kentucky studies, called phase 1 studies, examined just a few patients. The next phases are studies to see if there are negative side effects, and how well the stem cell therapy works for a larger group. A stem cell injection after a heart attack is not routine yet, but some day it could be.
This might be a game changer for treating heart failure. In fact, one of the researchers said it could be "the biggest advance in cardiology in [his] lifetime."[8] That's the best medical hope for a broken heart.
[1] "Heart Disease Facts," Centers for Disease Control and Prevention, http://www.cdc.gov/heartdisease/facts.htm (accessed August 27, 2012).
[2] Larry Husten, "Hype Aside, Hope for Stem Cell Therapy May Be Emerging From Hibernation," Forbes, November 11, 2011, http://www.forbes.com/sites/larryhusten/2011/11/15/hype-aside-hope-for-stem-cell-therapy-may-be-emerging-from-hibernation/ (accessed October 26, 2012).
[3] Leon M. Ptaszek, et al., "Towards Regenerative Therapy for Cardiac Disease," Lancet (379): 935-936.
[4] Raj R. Makkar, et al., "Intracoronary Cardiosphere-Derived Cells for Heart Regeneration after Myocardial Infarction (CADUCEUS): A Prospective, Randomised Phase 1 Trial," Lancet (379): 895-904. See also, "First-Of-Its-Kind Stem Cell Study Re-Grows Healthy Heart Muscle in Heart Attack Patients," ScienceDaily, February 13, 2012, http://www.sciencedaily.com/releases/2012/02/120213185441.htm (accessed October 25, 2012).
[5] Roberto Bolli, et al., "Cardiac Stem Cells in Patients with Ischemic Cardiomyopathy (SCIPIO): Initial Results of a Randomised Phase 1 Trial," Lancet (378): 1847-1857.
[6] Caleb Hellerman, "Studies: Stem Cells Reverse Heart Damage," CNN, November 14, 2011, http://www.cnn.com/2011/11/14/health/stem-cells-heart-damage-reverse/index.html (accessed August 27, 2012).
[7] Ibid.
[8] Ibid.