The 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 the heart.
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.