Role of cardiopulmonary bypass and arrested heart status in the early cell distribution after intracoronary infusion of bone marrow stromal cells.

Systemic distribution of bone marrow stromal cells (BMSCs) after intracoronary infusion (ICI) and the role of cardiopulmonary bypass (CPB) in cell distribution still remain unclear. This study was designed o analyze the cell distribution after ICI in variations of heart status in a swine myocardial infarction model.After inducing a myocardial infarction, iron oxide labeled male cells (1 x 10(8)) were infused through the coronary artery of the beating swine heart in Group 1. In Group 2, CPB was set up and then the same volume of cells was infused after cardioplegic arrest. In Groups 3 and 4, the animals underwent either beating or arrested ICI with the same volume of saline. Three days later, cell distribution was assessed by T2* change with magnetic resonance imaging and sex-determining region on Y-chromosome with quantitive polymerase chain reaction.Only a few transplanted cells were localized in the heart and no difference was found between Groups 1 and 2. The majority of BMSCs would be trapped in extracardial organs, and more cells resided in the spleen in arrested heart status.The majority of BMSCs transplanted by ICI would be entrapped by the extracardial organs. The arrested heart with CPB during ICI does not favor more cell retention in the injured myocardium. The optimal approach of delivery of BMSCs still needs further investigation.