Background: Transplantation of circulating progenitor cells (CPC) improves left ventricular function after successful recanalisation of chronic total occlusions at short-term follow-up. Cardiac magnetic resonance imaging (CMRI) is an excellent tool for serial assessment of underlying structural changes in perfusion, left ventricular function, and infarct size.
Methods: Twenty-eight patients with reperfused chronic total occlusion were randomised to CPC or inactive serum (control) infused into the target vessel. Serial CMRI was performed at baseline, after 3 and 15 months.
Results: Serial CMRI revealed an increase in ejection fraction in CPC (from 51+/-12% to 58+/-11% and 59+/-11%; p<0.01 versus baseline) and a decrease in endsystolic volume (from 74+/-30 ml to 65+/-30 ml and 63+/-31 ml; p<0.05 versus baseline). Infarct size decreased from 14.4+/-9.3% to 11.6+/-8.9% and 10.3+/-8.9% left ventricle (p<0.01 versus baseline). Myocardial perfusion revealed an improvement in affected segments from 1.50+/-0.17 to 1.76+/-0.16 and 1.82+/-0.20 (p<0.001). In control ejection fraction showed no increase at 3 (p=0.99) and a trend towards improvement at 15 months (p=0.07), whereas perfusion improved at 3 (p=0.01) and 15 months (p=0.004) follow-up.
Conclusions: Analysis of serial CMRI suggests that CPC application after chronic total occlusion recanalisation is associated with improved myocardial perfusion, reduction in infarct size and subsequent improved recovery of left ventricular function as compared to control at short- and long-term follow-up.