Healing a broken heart with stem cells?

The IMPACT-CABG (implantation of autologous CD133+ stem cells in patients undergoing coronary artery bypass grafting) protocol evaluates this experimental procedure, which is destined for patients suffering from ischemic heart disease, in which the blood supply to the heart is decreased and associated with heart failure. These patients undergo open-heart coronary bypass surgery, performed by the medical team to improve perfusion of the heart muscle. A few weeks ago, the first patient received progenitor CD133+ stem cells isolated from his bone marrow and enriched at the Cell Therapy Laboratory of the MRH, and has been doing very well ever since. Already, improvement has been noted in the contraction capacity of his heart, which has improved its ability to pump blood.

Objective of the intervention

The IMPACT-CABG study targets a group of patients who suffer heart muscle failure due to coronary heart disease. The goal is to add another treatment option to coronary bypass to promote healing and regeneration of the damaged heart muscle. This new procedure is less invasive and less expensive than heart transplant, the only treatment now available for patients with severe heart failure. The researchers plan to recruit a total of 20 patients throughout Québec in the first phase. A second Canadian centre, at the General Hospital of the University of Toronto, will also take part in the trial. In 2007, the CRCHUM, in collaboration with the MRH, began the COMPARE-AMI clinical trial, to evaluate the safety and feasibility of intramyocardial injection of stem cells (injecting them into the heart through a catheter) in a different group of patients who have suffered their first infarction.

Before the IMPACT-CABG trial, previous studies in other countries had also evaluated the safety and feasibility of injecting different stem cells in the hearts of patients with cardiac dysfunction. This is a first study in Canada evaluating intramyocardial injection of stem cells. "Also, no research team in the country had implemented such a complete treatment process, going from harvesting stem cells in the patient, treating them, and injecting them directly into the myocardium," states Dr. Nicolas Noiseux, cardiac surgeon at the CHUM and principal investigator in the study.

To prepare for the intervention, cells from the bone marrow harvested at the CHUM are transferred to the cell therapy laboratory of the MRH to isolate the most immature stem cells, which will be injected directly into the patient's heart.

The IMPACT-CABG protocol research team is composed of the following CRCHUM investigators and professors from the Université de Montréal's Faculty of Medicine: Drs. Nicolas Noiseux, Samer Mansour, and Louis-Mathieu Stevens, and from HMR, Dr. Denis-Claude Roy.

This research protocol was made possible through a collaboration of the CRCHUM, the Maisonneuve-Rosemont Hospital's Cell Therapy Laboratory, Miltenyi Biotech, the CHUM's Cardiology and Cardiac Surgery Services, the Radiology Department, Health Canada and the Fonds de la recherche en santé du Québec.