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Hope in Stem Cells for Thousands of Weak Hearts |
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By Mario Osava *
Brazilian doctors are beginning a pioneering study using stem cells in cardiac patients. If they are successful, in three years this new therapy could save as many as 200,000 lives in this South American nation.
RIO DE JANEIRO - Some four million people with serious cardiac disorders stand to benefit if a three-year Brazilian medical study of stem cell therapy proves successful.
The study aims to prove definitively the effectiveness of stem cells in the recovery of hearts affected by acute infarction, chronic ischemia (oxygen deficit from circulatory problems), dilation and Chagas disease.
Dozens of cardiac patients have already been treated using cell therapy in Brazil and other countries, with surprising positive results in the matter of weeks. But the initial phase in humans was focused primarily on verifying the safety of transplanting stem cells taken from bone marrow of each patient for recuperating the function of cardiac vessels and tissue.
Before it can be used more widely, this therapy must be tested on a greater number of patients for comparisons and to prove beyond a doubt that improvements are indeed the result of the stem cells, explained Bernardo Rangel Tura, cardiologist and researcher with the National Cardiology Institute of Laranjeiras (INCL), in Rio de Janeiro.
For this reason the Health Ministry decided to conduct the Multicentric Randomized Study for Cellular Therapy in Cardiopathies, involving 1,200 patients, with 300 from each of the four heart diseases studied. In each group, half will receive stem cells and the other half will receive the best available conventional treatments, and will serve as a basis for comparison.
Registration of volunteers has already begun, and the first operations will start in two months, said Tura.
In seeking results without subjective distortions, a randomized method was adopted, using lotteries to decide which patients would receive stem cell treatment. No one will know which patients are which until the end of the study, and only two of the researchers will be able to access that information in case of emergency, Tuna explained.
This way, the results will have statistical and comparative validity to determine whether the stem cells make a difference in treating heart diseases, he said.
It is the first study of its kind in the world with so many patients and ''all possible methodological safeguards,'' with no possibility to manipulate the outcome, the specialist added.
Once the new therapy is approved, the Health Ministry would make it available in Brazil's public health network, and could thus save 200,000 lives in three years, and save 15 million dollars a month in medical care. Each heart transplant, for example, costs eight times more than stem cell therapy, said Tura.
He stressed his ethical duty not to anticipate the study's conclusions, though he did venture to say that ''everything points'' to the effectiveness of the treatment.
Nelson Aguia is one of the sources of this optimism. Two heart attacks -- in 1983 and 1998 -- had weakened his heart despite seven bypass surgeries, forcing him to interrupt his work as a commercial representative. ''I was no longer able to walk up stairs... and was on the list for a heart transplant,'' he told Tierramérica.
Now, at 71, Aguia is retired, but he had returned to a normal work schedule ''through occupational therapy.'' He even has his doctors' approval to play football twice a month on small pitches. His recovery is seen as the result of therapy using stem cells taken from his own bone marrow.
Aguia was the first Brazilian to undergo the operation, in December 2001 at Rio de Janeiro's Pro-Cardiac Hospital. ''Three months later the result was excellent,'' he said.
At that time three other cardiac patients received the same treatment, ''improving their capacity for exertion and reducing ischemia,'' said André Souza, a doctor at the Pro-Cardiac Hospital, which treated 14 more patients in 2003 with similar results -- ''and the improvement is maintained two years later.''
One of the patients died 11 months after the operation from cerebral hemorrhage, and the autopsy of the heart ''indicated the formation of new cardiac muscle,'' said Souza. The transformation of marrow cells into muscle has not been proven, but experiments have made it ''quite clear that they do create blood vessels, promoting new vascularization,'' he said.
The objective of the Multicentric Study, in which the Pro-Cardiac is participating as a reference center, is not to prove this transformation or to reduce mortality, but rather to improve cardiac capacity and the quality of life of the patients, added the expert.
The same hospital was the scene in August 2004 of another unprecedented and promising event, when stem cells were introduced into the brain of Maria da Pomuceno, 54. The right side of her body was paralyzed as the result of a cerebral vascular rupture. Her recovery was exceptional: in less then three weeks she was able to walk again, understand what was being said to her, and to vocalize some sounds.
Similar experiments in Brazil are fuelling hopes for a cure or at least improvements for innumerable diseases, including diabetes, paralysis, Parkinson's, and many others that result from sclerosis or lesions of body organs.
* Mario Osava is an IPS correspondent.
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