The treatment, which was developed by British regenerative medicine company Celixir, involved injecting adult stem cells into heart muscle during bypass surgery. Heart failure is often caused by heart attacks, which permanently scar and weaken heart muscle, leaving the heart unable to pump blood effectively round the body. This is the first research to show reversal of that scarring and the apparent regeneration of the heart muscle.
Eleven patients with severe heart failure received the treatments in 2012 and 2013, which were carried out by surgeon Professor Steve Westaby of the John Radcliffe Hospital and specialists Dr Kryiakos Anastasiadis and Dr Polychronis Antonitsis of the General University Hospital of Thessaloniki.
Three years after the treatment, all 11 patients are still alive. 'Even in a small study you don't expect to see results this dramatic,' said Ajan Reginald, the co-founder of Celixir. 'The life expectancy for these patients is less than two years – we're excited and honoured that these patients are still alive.' Heart failure is incurable, and affects around 900,000 people in Britain. A third of patients admitted to hospital each year die within 12 months.
The cells, which go by the trademarked name Heartcel, are immuno-modulatory progenitor (iMP) cells, a type of adult stem cell that can differentiate into a variety of cell types – including muscle, bone and connective tissue. The cells also appear to reduce inflammation and promote regeneration. After the treatment, heart-muscle scarring was reduced by 40 percent, whereas typical drug therapies reduce scarring by only 5–10 percent. Patients also showed a 30 percent improvement in heart function and a 70 percent improvement in quality of life.
'We took these cells and put them into patients and had the most astonishing results. Scarred heart muscle doesn't really improve at all, so to see that happening was remarkable,' said Dr Westaby.
Jeremy Pearson, associate medical director at the British Heart Foundation, advised that a larger controlled trial is needed to clarify these results, noting that previous attempts to improve heart function through this method have largely failed. He cautioned: 'It is difficult to be sure that the cells had a beneficial effect because all patients were undergoing bypass surgery at the same time – which would usually improve heart function.'
The study was published in the Journal of Cardiovascular Translational Research. A larger trial will be carried out at the Royal Brompton Hospital in London later this year.