Study will examine treating heart damage with adult stem cells

Wednesday, November 8, 2006

Heart attacks most often result from obstructions on the vessels feeding the heart, the coronary arteries, and results in damage to the tissue of the heart. “Hardening” of the vessels (or atherosclerosis) is the main reason that the vessels become blocked. Risk factors are elevated cholesterol, obesity, smoking and high blood pressure.

Therapy with stem cells (e.g. for diseases like heart attack and stroke) derived from embyos is controversial. The use of the patient’s own stem cells, derived from his own bone marrow, could circumvene this problem. These cells are already used to regenerate bone marrow in patients who are given chemotherapy for leukemia and lymphoma, two types of cancer.

The UK Stem Cell Foundation (UKSCF) has made its first grant to support a unique project that promises hope for thousands of heart attack patients. The new procedure involves injecting the patient’s heart with his own bone marrow stem cells in the expectation that they will help repair the damaged heart and prolong the patient’s active life.

Two advantages claimed for this procedure are the overcoming of the ethical issues related to the use of embryonic stem cells and the reduction of the probability of tissue rejection.

The procedure will be carried out immediately after primary angioplasty, the opening up of blocked arteries, normally performed within the vital few hours after the heart attack.

The new procedure was designed by Dr Anthony Mathur, Senior Lecturer and Consultant Cardiologist, and Professor John Martin, British Heart Foundation Chair in Cardiovascular Sciences. The trial will involve about 100 patients and will be conducted at St Bartholomew’s Hospital.

Professor Peter Weissberg, Medical Director, British Heart Foundation welcomed research into the role stem cells may play in treating heart conditions and saw it as complementing the Foundation’s own research programme.

Some 600,000 patients survive heart attacks each year and the cost to the country may be as much as £7 billion taking into account not only hospitalisation and medical costs, but also the costs of lost working time. The bone marrow cell transplant is expected to improve the functionality of the damaged heart and increase greatly the capability of patients. It could have a significant economic effects also.

Nigel Hawkes in the Times today argues that it may be unwise to proceed when so little is understood about stem cells. Maybe it would be better to hold back until the science is better developed. He describes the procedure as coming from the “quick and dirty” school of medical research which has produced great benefits before the science has caught up. On the other hand he quotes Roger Pedersen, of the University of Cambridge as saying that we know little about what triggers cells to differentiate, and that “simple alchemy” will not work: “We’re going to have to do some science.” The feasibility and safety of the procedure has been tested in smaller studies, and the few reports available show a trend towards positive effects, but large clinical trials are still missing.