Purpose: This study assessed the effect of different levels of tracer uptake in the infarcted area on improvement of left ventricular function in patients treated by intracoronary mononuclear bone marrow cell (BMC) transplantation during long-term (12-month) follow-up.
Methods: Thirty-seven patients with irreversible injury after their first acute myocardial infarction, as confirmed by dobutamine echocardiography and sestamibi single-photon emission computed tomography/fluorodeoxyglucose positron emission tomography underwent BMC transplantation (1 × 10(8) cells), whereas 36 similar patients were randomly assigned to a control group.
Results: In 16 BMC-treated patients with very low sestamibi uptake (<30% of maximum) in the infarcted area, the mean baseline left ventricular ejection fraction (LVEF) increased at 3- and 12-month follow-up by 3% and 4% only, and mean end-diastolic/end-systolic volumes (EDV/ESV) enlarged by 20/7 mL and 23/9 mL, respectively (P = NS vs. controls). In 21 BMC-treated patients with higher sestamibi uptake (31%-50% of maximum), the LVEF improved by 6% and 7%, and EDV/ESV decreased by 4/13 mL and 1/13 mL, respectively (P < 0.05 vs. BMC-treated subgroup with low uptake and control subjects). There was no statistically significant difference in LVEF, EDV, or ESV changes between controls with low versus higher sestamibi uptake.
Conclusion: During long-term follow-up, the post-transplant improvement of left ventricular function remained significant only in BMC-treated patients with higher sestamibi uptake.