Retrograde delivery of stem cells: promising delivery strategy for myocardial regenerative therapy.

Heart failure is a leading cause of morbidity and mortality worldwide. The current strategies for treatment are limited, and new therapeutic approaches are needed. Experimental studies and clinical trials suggest that stem cell transplantation may improve cardiac function and prevent cardiac remodeling of the injured heart. Although the results of the studies were exciting, many problems remain to be resolved such as the best method of delivering the targeted cells. Direct injection into the myocardium and intracoronary artery infusion are the two most used methods of delivery in clinical settings. However, in a portion of patients with occluded coronary arteries and poor collaterals, transplanted cells may not reach the target ischemic lesion. To resolve this problem, we hypothesize that retrograde coronary venous delivery of stem cells may be a promising therapeutic strategy for the patients with occluded coronary arteries and poor collaterals.