Valvular and Vascular Repair and Regeneration
To treat cardiovascular diseases, clinicians and researchers are developing biological heart valves, identifying new stem cells, and finding ways to enhance blood vessel growth and repair.
Medication and surgery, which today are used to treat cardiovascular diseases such as valvular heart disease, peripheral artery disease and ischemic vascular disease, can often sufficiently manage patients' symptoms.
But as is the case with other complex conditions, even patients who receive the best available treatments are at risk of future complications, so there is a significant need for new regenerative therapies that treat the underlying sources of cardiovascular diseases.
Center for Regenerative Medicine clinicians and researchers led by Robert D. Simari, M.D., and Amir Lerman, M.D., both of Mayo Clinic in Rochester, Minn., are creating biological heart valves, identifying new stem cells, and developing ways to enhance blood vessel growth and repair.
Autologous biological heart valves. People with valvular heart disease may require surgery to repair or replace the damaged heart valve. While many mechanical and biological replacement options exist today, each has its drawbacks.
Center for Regenerative Medicine researchers plan to develop biological heart valves using a patient's own cells. After cells are removed from a donor heart — a process called decellularization — the cell-free tissue "scaffold" that remains would be populated with adult progenitor cells or induced pluripotent stem cells derived from the patient's cells.
These specially engineered cells would regrow within the scaffold, creating a new, patient-specific heart valve that would replace the patient's damaged valve, providing a living alternative to existing biological valve options.
Vascular progenitor cells. Blood vessels are often perceived as simple conduits or pipes through which blood flows. Recently, Peter J. Psaltis, MBBS, Ph.D., a research fellow in Dr. Simari's laboratory, discovered that blood vessels can make blood. Within the vessel wall, stem and progenitor cells were identified that have the capacity to generate white and red blood cells in adults.
The identification of these cells opens new avenues of research, such as better understanding their role in disease and determining if they can be targeted to prevent disorders in which blood cells play a role, including atherosclerosis and aneurysm formation.
Cardiovascular stem cell therapy. People with advanced cardiovascular disease have many unmet needs. Revascularization procedures are one option for restoring blood flow in people with ischemic heart disease and peripheral artery disease. In cases where revascularization is not possible or advisable, researchers are studying how stem cell therapy might be used to repair injured muscle or stimulate blood vessel growth (angiogenesis).
Some of the Center for Regenerative Medicine's research in this area is done in collaboration with the Cardiovascular Cell Therapy Research Network, a National Institutes of Health-sponsored group investigating the use of stem cell therapy for heart disease. Dr. Simari chairs the network.