Abstract 11770: Cardiac Biomarker Elevation during Stem Cell Mobilisation, Apheresis and Intramyocardial Delivery is Common but does not Impact Incidence of Long-Term MACE: An Analysis from ACT34-CMI
Background: Cardiac biomarker elevation has been described in small studies of intramyocardial cell delivery for cardiovascular disease, but the impact on long-term outcomes is unknown. ACT-34-CMI represents the largest regenerative therapy trial to date utilizing intramyocardial cell delivery.
Methods: ACT34-CMI was a randomized double-blind study assessing the utility of intramyocardial delivery of G-CSF mobilized and apheresed autologous CD34+ cells for the treatment of refractory angina. Troponin and CK(MB) systematically were assessed at baseline, after mobilization and apheresis, and post-intramyocardial injection.
Results: Seven (4.3%) of 167 subjects had troponin levels above the upper limits of normal (ULN) at baseline. Thirty-four (22.2%) and 11 (7.2%) subjects had troponin levels > ULN or >3x ULN after cell mobilization and apheresis, while 72 (46.1%) and 39 (25.2%) subjects had troponin elevations > ULN or > 3x ULN after intramyocardial injections. The interrelationship of troponin and CK(MB) elevation was poor. Peri-procedural troponin elevation either after apheresis (>ULN) or intramyocardial injection (>3x ULN) was largely asymptomatic (87%), associated with age but no other pre-procedural factors, and appeared to be associated with an increased risk of MACE in control, but not cell therapy-treated patients (Figure).
Conclusions: Troponin elevation in refractory angina patients occurs at baseline, is common after G-CSF mobilization, apheresis and intramyocardial administration, is usually asymptomatic, and does not appear to be associated with long-term MACE in those receiving cell therapy.
- © 2012 by American Heart Association, Inc.