Adult Stem Cells for Heart Regeneration
By John Fauber, Milwaukee Journal Sentinel, March 19, 2007
University of Wisconsin basketball games make Steve pop nitroglycerin tablets to relieve his chest pain. He is such a huge fan, that the games cause his angina to flare up, and each missed basket or lost possession is painful for him to watch; literally.
"A good basketball game is a three-nitro game for me," said Steve, 68.
His doctors however, haven’t told him to stay away from the TV set. If the Badgers are causing him to think twice about watching basketball games, then the Badgers want to do something about it.
Using a patient’s own cells to treat heart disease, Steve became the first patient to enter a new stem cell clinical trial at the University of Wisconsin.
So they could be injected into several blood-deprived areas of Steve’s heart, doctor’s at the University of Wisconsin Hospital and Clinics harvested adult stem cells from Steve’s bone marrow. With the expectation of restoring proper blood flow, the stem cells should be able to expand existing vessels and also form new ones.
“Heart cells cannot be replaced, and what we are born with is what we get for the rest of our lives.” This has been the gloomy belief overhanging cardiology for decades. But this new trial could put an end to the bleak thought.
As researchers have begun an assortment of human experiments using growth factors, genes, and adult stem cells to fix damaged hearts, the field of regenerative medicine has gained promise over the last several years.
About 10 patients will be treated at the University of Wisconsin Hospital, but a total of approximately 150 people will be treated around the country as part of the trial.
Conventional therapies such as angioplasty or bypass surgery are often powerless to treat the blockages of blood vessels that are associated with chronic myocardial ischemia since they are frequently too small. An estimated 125,000 to 250,000 people develop the condition each year nationally.
Drugs such as nitroglycerin are the only option left for alleviating the chest pain in patients.
Steve takes nitroglycerin tablets that dissolve under his tongue for eight hours a day, but the other 16 require him to wear a time-release nitroglycerine patch.
The mere act of walking only a block, causes his chest pain to erupt.
"I used to love to walk," he said. "I would do anything to get rid of this. If they could snip these two (blocked) blood vessels, even if it killed a little bit of the heart muscle, I'd do it in a minute."
Failing to relive his chest pain, Steve already tried angioplasty and coronary bypass surgery.
A placebo or control group of patients must be used for a clinical trial to be truly accurate.
For Steve’s trial, one-third will be injected with a placebo saline solution, another third will get 10 million stem cells, and the last third will be injected with about 50 million stem cells.
None of the patients will be aware of which group they are in, and the doctors will be left in the dark in regards to this specific information as well.
Two days prior to his treatment Steve says, “I feel optimistic that I'm going to get the stem cells and that it is going to work.”
Steve and his wife, Dagny, have enthusiasm for him to be in the trial. And this is even if it turns out that he is among the placebo group that is receiving the saline injection.
Born with a serious congenital heart defect, the couple’s 9-year-old granddaughter could someday benefit from a breakthrough in stem cell research says Steve’s wife.
"That's what we hope," she says.
A sensor is threaded up through an artery in Steve’s groin all the way up to his left ventricle. It is late in the afternoon and Steve lies in the cardiac catheterization lab with the sensor in the main pumping chamber of his heart.
Electrical impulses and movement in the heart tissue are both indicators of blood flow, and the sensor is designed to detect these very signals.
"No signal is dead (tissue)," says cardiologist Matthew. "Strong is normal. Weak is viable but impaired blood flow. That's where we want to go."
After a couple of hours, Matthew and another cardiologist named Amish create a multicolored map of the blood flow in Steve's heart.
In the lower back section of the chamber, the two doctors zero in on an approximately 1-inch by ¼-inch oblong area. It is into 10 different spots in this area, that the syringes will inject the clear treatment fluid.
Measuring in at 8 millimeters at its thinnest point, is the wall of Steve’s ventricle. Amish removes the injection catheter from its packaging and sets the length of the tip.
"We need to go half of that," Amish says.
One of the several tiny but serious risks in the procedure is puncturing the wall.
The injection sites are selected by Matthew and Amish.
Each injection lasts anywhere from 30 to 40 seconds, and the first one is administered at 4:40 p.m.
Steve moves on the table. He is awake but has been sedated.
"Keep your arm down, Steve," Amish says. "You can't move."
"Can I get another nitro?" Steve asks.
A nurse puts a nitro tablet in his mouth.
The final injection is made at 5:11 in the afternoon.
Amish says that any lessening of the angina won’t be noticeable for at least a few months if the treatment proves to be successful.
Steve is feeling well, but is still just a bit tired two days following the procedure.
"I'm bruised and full of holes," he jokes.
A cruise of the Greek islands is on the agenda for Steve and his wife in August.
"I'd love to be able to go up the steps of the Parthenon," he says. "But if I have to, I'll just sit on the beach with a novel."
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