Injecting patients’ own stem cells directly into their heart muscle may be a safe new treatment for heart failure.
In patients with severe ischemic heart disease, or coronary artery disease, the gradual buildup of waxy plaque in the heart’s arteries can lead to chest pain, heart attack, and heart failure. This is the number one cause of death in the U.S., and while treatments exist, sometimes scar tissue interferes with heart function, and many patients continue to suffer symptoms.
In a placebo-controlled, double-blind, randomized trial (MSC-HF Trial, phase II), a type of stem cell called mesenchymal stromal cells were directly injected into the heart muscle of patients with chronic ischemic heart failure.
The cells were first isolated from bone marrow extracted from the patients themselves beforehand, and then cultured. Using a catheter inserted in the groin (which required only local anesthesia), the researchers were able to use sensors to track heart movement and voltage, the combination of which “can give you a feeling of what is the normal heart tissue and what is the scarred tissue," lead researcher Anders Bruun Mathiasen of the Rigshospitalet University Hospital Copenhagen tells U.S. News and World Report.
Then, for the bone marrow-derived stem cells, the researchers ran a long needle up the catheter and made about a dozen small injections into portions of the heart that were scarred. By injecting between the living and dead heart muscle, they hoped to extend the amount of living muscle while reducing the scarring that’s already there.
Six months later, those who received the stem cell injections had improved heart pump function, compared with those who got a placebo (of saline). By the end of the 59-person trial, treated patients showed an 8.2-milliliter decrease in end systolic volume -- the lowest volume of blood in the heart during the pumping cycle. It’s a key measure of the heart's ability to pump effectively. The placebo group showed an increase of 6 milliliters in end systolic volume.
The treatment likely works because it facilitates the growth of new blood vessels and new heart muscle, Mathiasen explains in a news release. Scar tissue was also reduced in the treated patients, though the amount wasn’t statistically significant.
The team will continue to monitor the patients in the long term. This was the second largest randomized trial to test stem cell injection in treating heart disease, but a larger, phase III clinical trial is needed before the treatment will be approved.
The findings were presented this week at the American College of Cardiology’s 63rd Annual Scientific Session in Washington. “Hallway Buzz” videos about the MSC-HF trial here and here.
Image: BruceBlaus via Wikimedia