Multi-modality imaging in the patients with myocardial infarction after coronary artery bypass graft and autologous bone marrow stem cell transplantation

Objective To evaluate the value of multi-modality imaging (PET/CT+ CAG+ CMRI) in post myocardial infract (MI) patients followed coronary artery bypass graft (CABG) and autologous bone marrow stem cell (BMSC) therapy. Methods A total of 43 patients with MI (27 males, 16 females, age range: 47-72 years) were prospectively enrolled in the year 2012 between January and December. All patients underwent CABG+ BMSC transplantation and were divided into 3 groups according to the time interval between two treatments (group 1: 0-3 d; group 2: 4-14 d; group 3: 15-30 d). All patients were orderly scanned with CMRI, PET/CT (13N-NH3·H2O/18F-FDG) and CAG at different time-points pre-/post- treatment. The quantitative parameters included vascular stenosis degree(VSD), LVEF, percentage size of infarction (PSI), the number of segments in mismatched myocardial perfusion/metabolic and the K value for radioactive distribution grading. One-way analysis of variance and the least significant difference t test were used to compare parameters before and after treatment in the same group and among three different groups. Results Regarding PET/CT diagnostic efficacy of abnormal myocardial segments, the sensitivity, specificity, positive predictive value and negative predictive value were 95.4%(540/566), 87.3%(144/165), 96.3%(540/561) and 84.7%(144/170), respectively. After CABG and BMSC transplantation treatments for 12 months, VSD decreased significantly((69.1±9.5)%; F=12.854, P 0.05). PSI of patients in group 2 decreased greatly after 12 months treatment ((35.70±12.59)%; F=3.792, t values: -2.916-4.059, all P 0.05). Conclusions Multi-modality imaging may be used for accurately detecting abnormal myocardium and predicting prognosis. CABG+ BMSC therapy during day 4-14 post-MI may temporarily improve perfusion and metabolism in viable myocardium, but the long term prognosis seemed not be improved. Key words: Myocardial infarction; Stem cell transplantation; Transplantation, autologous; Coronary artery bypass; Position-emission tomography; Tomography, X-ray computed; Coronary angiography; Magnetic resonance imaging