Abstract 17537: Long-Term Improvement of Left Ventricular Function and Infarct Size After Cardiac Stem Cell Therapy: 5-Years Follow-Up of the MYSTAR Study
Background. Combined (intramyocardial and intracoronary) delivery of autologous bone marrow mononuclear cells (BM-MNC) (MYSTAR study, n=60) resulted in a moderate but significant increase in global left ventricular ejection fraction (LV EF) in patients with recent acute myocardial infarction (AMI) and LV EF between 30-45%. The long-term (5 years) effect of the cardiac stem cell therapy was evaluated on the clinical outcome, size of myocardial infarction and LV EF.
Methods. MACCE was defined as all-cause mortality, re-AMI, target vessel revascularization of the infarct-related artery (TVR) and stroke) and implantation of automatic cardioverter-defibrillators (AICD). LV function was investigated by transthoracic echocardiography, and by cardiac magnet resonance imaging (CMR) in a subgroup of patients. Infarct size was evaluated by myocardial scintigraphy (SPECT).
Results. Four patients were lost to FUP. MACCE occurred in 16.1% of the 56 patients. Five patients (8.9%) died 46±18 month post cardiac BM-MNC therapy due to pulmonary embolism, aortic valve insufficiency, or heart failure, 3 patients underwent TVR and 5 patients received AICD. LV EF increased significantly from pre-BM-MNC therapy (baseline) to 1-year and 5-year FUP (39.2±9.3% to 41.5±8.3 and 44.8±10.3%, p=0.001 between baseline and 5-year FUP), while trend towards decrease in LV end-diastolic volume was measured. Infarct size decreased from 27.4±10.7% to 24.3±11.6% and 20.1±11.8%, respectively (p=0.002 between baseline and 5-year FUP). Patients with MACCE had a significantly lower baseline unipolar voltage value (UPV) of the intramyocardially injected area (6.3±2.4 vs 8.2±3.0 mV, p=0.042) assessed by NOGA endocardial mapping. Mortality was associated with lower baseline 99m-Tc-Sestamibi tracer uptake (44.2±15.4% vs 58.4±15.6%, p=0.042), UPV (4.8±1.2 vs 8.3±2.7 mV, p=0.002) and local linear shortening (index of segmental wall motion disturbance) (7.4±3.2% vs 11.1±3.7%, p=0.021) in the injected area.
Conclusions. Combined delivery of BM-MNC leads to a stably improvement of LV EF and size of infarction over 5 years with favorable event-free survival rate in patients with a low (30-45%) EF post-AMI.
- © 2012 by American Heart Association, Inc.