A Randomized Study of Autologous Bone Marrow Derived Stem Cells in Pediatric Dilated Cardiomyopathy

This pilot study is of a randomized, crossover, placebo controlled design. The Consolidated Standards of Reporting Trials (CONSORT) statement was used to guide the development of the protocol. Ethical Approval was obtained for this project in April 2008.

A CONSORT flow diagram was produced and a project plan for a crossover study designed. Although the primary end point of the study was safety and feasibility the investigator aimed to look at functional outcome as a secondary endpoint. Statistical review of the available literature indicated a 3% change in ejection fraction (EF) as measured by magnetic resonance imaging (MRI) would represent a meaningful change and calculated 10 patients would be sufficient to detect this mean change in EF, assuming a SD of difference of 3% with 80% power and 5% significance. For all calculations it was assumed that the distribution of differences was Normal. Calculation of a sample size for the crossover study required a definition of the minimum difference to be detected.

Children aged 1 year to 16 years at review, either attending Heart Failure Clinic at Great Ormond Street Hospital (GOSH) or referred for admission and management of their heart failure at GOSH will be invited to participate in the study. The lower age limit was selected to permit coronary artery catheterisation to be feasibly performed taking into account the size of the patient.

On recruitment all patients have impaired systolic function as determined by reduced shortening fraction on echocardiogram (more than 2 SD below normal). The functional status of the recruited patients was class 2-4 as defined by the NYHA or Ross classification.

Exclusion criteria were the need for high dependency or intensive care and congenital heart disease, viral infection that would preclude the use of hospital Cell Therapy Laboratory facilities, active malignancy and unstable cardiac drug therapy.