Effects of Transendocardial CD34 + Cell Transplantation on Diastolic Parameters in Patients with Nonischemic Dilated Cardiomyopathy

We sought to evaluate the physiological background and the effects of CD34 + cell transplantation on diastolic parameters in nonischemic dilated cardiomyopathy patients (DCM). We enrolled 38 DCM patients with NYHA class III and LVEF < 40% who underwent transendocardial CD34 + cell transplantation. Peripheral blood CD34 + cells were mobilized by G‐CSF, collected via apheresis, and injected transendocardially in the areas of myocardial hibernation. Patients were followed for 1 year. At baseline, estimated filling pressures were significantly elevated (E/e′ ≥ 15) in 18 patients (Group A), and moderately elevated (E/e ′< 15) in 20 patients (Group B). The groups did not differ in age (54 ± 9 years vs. 52 ± 10 years; p  = .62), gender (male: 85% vs. 78%; p  = .57), or LVEF (31 ± 7% vs. 34 ± 6%; p  = .37). When compared to Group B patients in Group A had more segments with myocardial scar (4.9 ± 2.7 vs. 2.7 ± 2.9; p  = .03), myocardial hibernation (2.2 ± 1.6 vs. 0.9 ± 1.1; p  = .02), and longer average local relaxation time on electroanatomical mapping (378 ± 41 ms vs. 333 ± 34 ms, p  = .01). During follow‐up there was an improvement in diastolic parameters in Group A (E/e′: from 24.3 ± 12.1 to 16.3 ± 8.0; p  = .005), but not in Group B (E/e′: from 10.2 ± 3.7 to 13.2 ± 9.1; p  = .19). Accordingly, in Group A, we found an increase in 6‐minute walk distance (from 463 ± 83 m to 546 ± 91 m; p  = .03), and a decrease in NT‐proBNP (from 2140 ± 1743 pg/ml to 863 ± 836 pg/ml; p  = .02). In nonischemic DCM, diastolic dysfunction appears to correlate with areas of myocardial scar and hibernation. Transendocardial CD34 + cell transplantation may improve diastolic parameters in this patient cohort. S tem C ells T ranslational M edicine 2017;6:1515–1521