Effects of transendocardial CD34+ cell transplantation in patients with ischemic cardiomyopathy.

BACKGROUND We investigated the effects of transendocardial CD34(+) cell transplantation in patients with ischemic cardiomyopathy. METHODS AND RESULTS In a prospective crossover study, we enrolled 33 patients with ischemic cardiomyopathy with New York Heart Association class III and left ventricular ejection fraction <40%. In phase 1, patients were treated with medical therapy for 6 months. Thereafter, all patients underwent transendocardial CD34(+) cell transplantation. Peripheral blood CD34(+) cells were mobilized by granulocyte colony stimulating factor, collected via apheresis, and injected transendocardially in the areas of hibernating myocardium. Patients were followed up for 6 months after the procedure (phase 2). Two patients died during phase 1 and none during phase 2. The remaining 31 patients were 85% men, aged 57±6 years. In phase 1, we found no change in left ventricular ejection fraction (from 25.2±6.2% to 27.1±6.6%; P=0.23), N-terminal pro B-type natriuretic peptide (from 3322±3411 to 3672±5165 pg/mL; P=0.75) or 6-minute walk distance (from 373±68 to 411±116 m; P=0.17). In contrast, in phase 2 there was an improvement in left ventricular ejection fraction (from 27.1±6.6% to 34.9±10.9%; P=0.001), increase in 6-minute walk distance (from 411±116 to 496±113 m; P=0.001), and a decrease in N-terminal pro B-type natriuretic peptide (from 3672±5165 to 1488±1847 pg/mL; P=0.04). The average number of injected CD34(+) cells was 90.6±7.5×10(6). Higher doses of CD34(+) cells and a more diffuse distribution of transendocardial cell injections were associated with better clinical response. CONCLUSIONS Transendocardial CD34(+) cell transplantation may be associated with improved left ventricular function, decreased N-terminal pro B-type natriuretic peptide levels, and better exercise capacity in patients with ischemic cardiomyopathy. These effects seem to be particularly pronounced in patients receiving diffusely distributed cell injections and high-dose cell therapy. CLINICAL TRIAL REGISTRATION URL http://www.clinicaltrials.gov. Unique identifier: NCT01350310.