Two Stem Cell Studies Show Heart Tissue Regeneration Following Infarcts
Evidence that bone-marrow stem-cell transplantation could regenerate damaged cells in the heart after myocardial infarction is demonstrated by separate research among teams in Germany and China.
Dr. Gustav Steinhoff and colleagues from the department of cardiac surgery, University of Rostock, Germany, injected six patients with bone-marrow stem cells into areas of the heart which had died as a result of myocardial infarction. These patients had also received conventional coronary artery bypass grafting (CABG). All patients were alive and well after surgery, and five of them had strikingly improved blood flow to the heart, suggesting that the stem cells may have induced angiogenesis in previously damaged areas.
Dr. Steinhoff and colleagues said that while they have shown that local bone-marrow stem-cell implantation for myocardial regeneration together with CABG is safe, “whether a larger number of cells than that which we used will be tolerated is unclear.”
“We emphasize that all reported attempts of clinical cell transplantation for myocardial regeneration, including our study, have been done in association with surgical or interventional revascularisation, so that the effectiveness of cell transplantation alone cannot be readily assessed,” they write. “Controlled studies are needed to clarify the role of cell transplantation in myocardial regeneration.”
In the second study, Dr. Hung-Fat Tse and colleagues at the division of cardiology, University of Hong Kong, implanted autologous mononuclear bone marrow cells into the ischaemic myocardium of eight patients with severe ischaemic heart disease. The procedure was guided by electromechanical mapping with a percutaneous catheter procedure. At three months follow-up there was improvement in symptoms, myocardial perfusion, and function at the ischaemic region on magnetic resonance imaging.
Dr. Tse and colleagues stated that they “have demonstrated that catheter-based percutaneous delivery of the patient’s own bone-marrow stem-cells into the heart muscle for blood-vessel regeneration is a safe and feasible procedure for patients with coronary heart disease which cannot be treated by medical or interventional therapy.”
“We have observed an improvement in blood flow to the heart after the procedure, and further studies are planned to evaluate the clinical impact of this therapy in larger, controlled populations,” they write. “Furthermore, the exact type of marrow stem-cells effective in heart-tissue regeneration will need to be defined.”
Lancet 2003; 361:45-46;47-49.
