world's first clinical trial using patients' own cardiac stem cells to repair
heart damage has produced surprising results. The preliminary trial was designed
simply to test the safety of the procedure, but doctors observed an unexpected
improvement in heart function in patients receiving the treatment.
Professor Roberto Bolli, the lead researcher from the
University of Louisville in the US, said: 'The results are striking. If these
results hold up in future studies, I believe this could be the biggest
revolution in cardiovascular medicine in my lifetime'.
The trial included 14 patients that were undergoing
heart bypass surgery following a heart attack. During the surgery a section of
tissue from a healthy region of the heart was removed and the cardiac stem
cells extracted. The cells were cultured in a dish until there were around a million of them before being injected back into
Four months after the injection, the average heart
function of the 14 patients (measured as the percentage of blood pumped out of
the heart with every beat) had risen from 30.3 percent before treatment to 38.5
percent. There were also reductions in tissue damage and patients reported
improvements in their quality of life. Seven control patients who did not receive
the stem cell injection did not show any improvement.
Professor Bolli said: 'We believe these findings are
very significant. Our results indicate that cardiac stem cells can markedly
improve the contractile function of the heart'.
This is the first human trial to use stem cells from a
patient's own heart tissue to repair damage. Several studies have previously
shown that stem cells derived from bone marrow can have a similar effect on
heart function, and trials using these cells are at a much more advanced stage.
However Professor Bolli believes that using cardiac stem
cells is preferable as 'their natural function is to replace the cells that
continuously die in the heart due to wear and tear'.
Professor Peter Weissberg, medical director at the British
Heart Foundation added: 'Unlike many previous studies, this research has used
cells derived from the patients' own hearts, rather than from blood or bone
marrow. Their preliminary findings, in a small number of patients, showed a
modest improvement in heart function - this is similar to those reported in
other cell therapy studies'.
'This is positive, but the crucial next steps are to
see whether this improvement is confirmed in the final completed trial, and to
understand whether the cells are actually replacing damaged heart cells or are
secreting molecules that are helping to heal the heart'.
The research was conducted in conjunction with Harvard
Medical School and is published in The Lancet.