Bone marrow stem cell therapy in cardiovascular disorders

Bone marrow stem cell therapy in cardiovascular disorders

Bone marrow stem cell therapy in cardiovascular disorders: It has been over a decade since Strauer BE and colleagues used intracoronary human autologous bone marrow derived stem cell transplantation for myocardial regeneration following myocardial infarction to treat left ventricular failure [Strauer BE, Brehm M, Zeus T, et al. Intracoronary human autologous stem cell transplantation for myocardial regeneration following myocardial infarction Dtsch Med Wschr 2001;126:932-938].

Purified bone marrow stem cells were used intramyocardially following coronary artery bypass grafting to improve heart failure in the same year by Stamm C and associates [Autologous bone-marrow stem-cell transplantation for myocardial regeneration Lancet 2003;361:45-46]. Since then it has been tried in the treatment of dilated cardiomyopathy and ischemic heart failure. Bone marrow stem cells can proliferate and differentiate into various types of cells. The advantage of bone marrow derived stems cells is that it is a renewable source and easily accessible. There are no ethical issues involved either. Currently automated systems are available, which do away with the disadvantages of a manual processing system.

Methods of delivery of stem cells to the heart

• Intravenous injection
• Intracoronary injection under balloon occlusion
• Injection through the coronary sinus
• Transarterial endocardial injection
• Per operative intramyocardial injection either during cardiac surgery or with a mini lateral thoracotomy or an epicardial collagen/stem cell patch

The cardiac retention rate of bone marrow stem cells is low, of the order of two to three percent only. In intracoronary application, the stem cells are infused during PTCA (percutaneous transluminal coronary angioplasty) which prevents back flow and facilitates migration into the infarcted zone. Better migration occurs into injured and ischemic myocardial tissue. Stem cell specific adhesion molecules may also aid this process. Transendocardial delivery uses NOGA injection catheter introduced retrogradely from the arterial route into the left ventricular cavity for injection into the subendocardial region. This technique has its inherent risks including potential for ventricular arrhythmias and cardiac tamponade. An updated review on the topic is available in JACC [J Am Coll Cardiol, 2011; 58:1095-1104].