Long-term outcome of fetal cell transplantation on postinfarction ventricular remodeling and function.

OBJECTIVES

The purpose of this study was to determine the long-term outcome of fetal cell transplantation into myocardial infarction on left ventricular (LV) function and remodeling.

BACKGROUND

While neonatal cell transplantation improved function for acute myocardial infarction, long-term data on the effects of cell-transplant therapy using a more primitive cell on ventricular remodeling and function are needed.Methods. - Therefore, we injected 4 x 10(6) Fischer 344 fetal cardiac cells or medium into 1-week old infarcts in adult female Fischer rats to assess long-term outcome.

RESULTS

Ten months after transplantation histologic analysis showed that cell implants were readily visible within the infarct scar. Infarct wall thickness was greater in cell-treated at 0.69 +/- 0.05 mm (n = 11) vs. medium-treated hearts at 0.33 +/- 0.01 mm (n = 19; P = 0.0001). Postmortem LV volume was 0.41 +/- 0.04 ml in cell-treated vs. 0.51 +/- 0.03 ml in medium-treated hearts (P < 0.04). Ejection fraction assessed by LV angiography was 0.40 +/- 0.02 in cell-treated (n = 16) vs. 0.33 +/- 0.02 in medium-treated hearts (n = 24; P < 0.03) with trends towards smaller in vivo end-diastolic and end-systolic volumes in cell-treated vs. medium-treated hearts. Polymerase chain reaction analysis of the Sry gene of the Y chromosome was positive in four of five cell-treated and zero of five medium-treated hearts confirming viability of male cells in female donors.

CONCLUSION

Over the course of 10 months, fetal cardiac cell transplantation into infarcted hearts increased infarct wall thickness, reduced LV dilatation, and improved LV ejection fraction. Thus, fetal cell-transplant therapy mitigated the longer-term adverse effects of LV remodeling following a myocardial infarction.