c-kit-positive, lineage-negative cardiac stem cells (CSCs) improve post-infarction
left ventricular (LV) dysfunction when administered to animals. We undertook a phase
1 trial (Stem Cell Infusion in Patients with Ischemic cardiOmyopathy [SCIPIO]) of
autologous CSCs for the treatment of heart failure resulting from ischaemic heart
disease.
In stage A of the SCIPIO trial, patients with post-infarction LV dysfunction (ejection
fraction [EF] ≤40%) before coronary artery bypass grafting were consecutively enrolled
in the treatment and control groups. In stage B, patients were randomly assigned to
the treatment or control group in a 2:3 ratio by use of a computer-generated block
randomisation scheme. 1 million autologous CSCs were administered by intracoronary
infusion at a mean of 113 days (SE 4) after surgery; controls were not given any treatment.
Although the study was open label, the echocardiographic analyses were masked to group
assignment. The primary endpoint was short-term safety of CSCs and the secondary endpoint
was efficacy. A per-protocol analysis was used. This study is registered with ClinicalTrials.gov,
number NCT00474461.
This study is still in progress. 16 patients were assigned to the treatment group
and seven to the control group; no CSC-related adverse effects were reported. In 14
CSC-treated patients who were analysed, LVEF increased from 30·3% (SE 1·9) before
CSC infusion to 38·5% (2·8) at 4 months after infusion (p=0·001). By contrast, in
seven control patients, during the corresponding time interval, LVEF did not change
(30·1% [2·4] at 4 months after CABG vs 30·2% [2·5] at 8 months after CABG). Importantly,
the salubrious effects of CSCs were even more pronounced at 1 year in eight patients
(eg, LVEF increased by 12·3 ejection fraction units [2·1] vs baseline, p=0·0007).
In the seven treated patients in whom cardiac MRI could be done, infarct size decreased
from 32·6 g (6·3) by 7·8 g (1·7; 24%) at 4 months (p=0·004) and 9·8 g (3·5; 30%) at
1 year (p=0·04).
These initial results in patients are very encouraging. They suggest that intracoronary
infusion of autologous CSCs is effective in improving LV systolic function and reducing
infarct size in patients with heart failure after myocardial infarction, and warrant
further, larger, phase 2 studies.
University of Louisville Research Foundation and National Institutes of Health.
Copyright © 2011 Elsevier Ltd. All rights reserved.