Abstract

Objective: To investigate the kinetics of myocardial engraftment of bone marrow-derived mononuclear cells (BMNCs) after intracoronary injection using ^99mTc-d,l-hexamethylpropylene amine oxime (^99mTc-HMPAO) nuclear imaging in patients with acute and chronic anterior myocardial infarction.

Design: Nuclear imaging-derived tracking of BMNCs at 2 and 20 h after injection in the left anterior descending (LAD) coronary artery.

Setting: Academical cardiocentre.

Patients: Five patients with acute (mean (SD) age 58 (11) years; ejection fraction range 33–45%) and five patients with chronic (mean (SD) age 50 (6) years; ejection fraction range 28–34%) anterior myocardial infarction.

Interventions: A total of 24.2×10⁸–57.0×10⁸ BMNCs (20% labelled with 700–1000 MBq ^99mTc-HMPAO) were injected in the LAD coronary artery.

Results: At 2 h after BMNC injection, myocardial activity was observed in all patients with acute (range 1.31–5.10%) and in all but one patient with chronic infarction (range 1.10–3.0%). At 20 h, myocardial engraftment was noted only in three patients with acute myocardial infarction, whereas no myocardial activity was noted in any patient with chronic infarction.

Conclusions: Engraftment of BMNCs shows dynamic changes within the first 20 h after intracoronary injection. Persistent myocardial engraftment was noted only in a subset of patients with acute myocardial infarction.