Dilated cardiomyopathy occurs when the heart muscle stretches and becomes weakened, leading to less efficient pumping of the blood throughout the body. It is the most common form of non-ischemic cardiomyopathy (not due to coronary artery disease). Dilated cardiomyopathy may be associated with damage to the heart muscle from a variety of causes such as inflammation, infections, and toxic substances. Diastolic dysfunction seen in patients with dilated cardiomyopathy refers to insufficient relaxation and filling of the ventricles during the second part of the heart-pumping phase (leading to increased pressure in the ventricles).
A group of scientists previously showed that partial reversal of dilated cardiomyopathy is possible by introducing CD34+ hematopoietic stem cells to the heart muscle and coronary artery. This effect is thought to be due to ventricular remodeling and effects on the heart muscle microcirculation (small vasculature embedded within the heart muscle). Altered microcirculation also affects ventricular relaxation; therefore scientists conducted a study to determine if cell therapy with CD34+ cells can affect diastolic function in patients with dilated cardiomyopathy.
To conduct the study, CD34+ cells were isolated from the peripheral blood from two groups of patients based on level of diastolic dysfunction. The cells were then injected into the patients’ muscle tissue (trans-endocardial) where contractile function abnormalities were evident via a special technique to visualize the muscle anatomy (electro-anatomical mapping). The patients were monitored at various time points for up to a year. Various clinical evaluations were made including exercise tests and echocardiography. Electro-anatomical mapping was performed again at the end of the study to determine any changes in diastolic function.
In the group of patients with elevated ventricular filling pressures, there was significant improvement of this parameter after CD34+ cell therapy. This was not the case in the group with lower filling pressures. The magnitude of diastolic dysfunction decreased in the group with elevated ventricular filling pressures. The results suggest that the CD34+ cell therapy improved ventricular filling pressures, and therefore, diastolic function. Continued studies can help better define the mechanisms of CD34+ therapy in heart health improvement for potential application in other forms of heart failure.
Reference: Bervar M, e. (2017). Effects of Transendocardial CD34+ Cell Transplantation on Diastolic Parameters in Patients with Nonischemic Dilated Cardiomyopathy. - PubMed - NCBI . Ncbi.nlm.nih.gov. Retrieved 6 April 2017, from https://www.ncbi.nlm.nih.gov/pubmed/28296283