In the trial, cardiac stem cells were used to repair the severely damaged hearts of 16 patients. It was the first time this had ever been done in humans.
After one year the ejection fraction or “pumping efficiency” of the hearts of eight patients had improved by more than 12%. All patients whose progress was followed underwent some level of recovery.
The results tripled the 4% improvement researchers had expected to see.
Although this was an early stage trial and larger studies are needed, scientists believe the promise it shows has huge implications.
Professor Roberto Bolli, one of the research leaders from the University of Louisville in the US, said:
“If these results hold up in future studies, I believe this could be the biggest revolution in cardiovascular medicine in my lifetime.”
A total of 23 patients took part in the “Scipio” trial, all of whom had suffered heart failure due to a previous heart attack. Sixteen were assigned to the stem cell therapy while the other seven received standard care.
Heart failure occurs when a damaged heart is weakened and unable to pump enough blood around the body. It is commonly caused by a heart attack and can lead to serious disability and a shortened life.
The ground-breaking new treatment involved extracting cardiac stem cells (CSCs) — self-renewing cells that rebuild hearts and arteries — from patients during bypass surgery.
The cells were purified and grown in the laboratory before being injected back into damaged regions of the patients’ hearts four months later. A million CSCs were infused into each patient viaa balloon catheter, an expandable device used to open up arteries.
Heart pumping efficiency is assessed by measuring the fraction of blood expelled or “ejected” from the left ventricle with each beat.
Over a period of four months patients who underwent the treatment saw an 8.5% improvement in LVEF. After one year, this increased to 12.3%.