Biomedical Engineering Reference
In-Depth Information
safety and effectiveness of this procedure has yet to be established by randomized
controlled trials.
Smits et al. reported on the procedural and 6-month results of the first percutane-
ous and stand-alone study (
n
=5) on myocardial repair with autologous skeletal
myoblasts [
80
]. All cell transplantation procedures were uneventful, and no serious
adverse events occurred during follow-up. One patient received an implantable
cardioverter-defibrillator after transplantation because of asymptomatic runs of
non-sustained ventricular tachycardia. Compared with baseline, the left ventricular
ejection fraction (LVEF) increased from 36 ± 11 to 41 ± 9% (3 months,
p
= 0.009)
and 45 ± 8% (6 months,
p
= 0.23). Regional wall analysis by MRI showed significantly
increased wall thickening at the target areas and less wall thickening in remote areas
(wall thickening at target areas vs. 3 months follow-up: 0.9 ± 2.3 mm vs. 1.8 ± 2.4 mm,
p
= 0.008). The authors concluded that this pilot study was the first to demonstrate
the potential and feasibility of percutaneous skeletal myoblast delivery as a stand-
alone procedure for myocardial repair in patients with post-infarction heart failure.
More data are needed to confirm its safety and explain the phenomenon. Ince et al.
stated that transcatheter transplantation of autologous skeletal myoblasts for severe
left ventricular dysfunction in post-infarction patients is feasible, safe, and promis-
ing. These authors further stated that scrutiny with randomized, double-blinded,
multicenter trials appears warranted [
81
]. This is in agreement with the observation
of Siminiak et al. who stated that autologous skeletal myoblast transplantation for
the treatment of post-infarction heart failure is feasible, and that further research is
needed to validate this method in a clinical practice [
82
] .
Wollert et al. reported that injection of autologous bone marrow stem cells into
the coronary arteries improved heart function in patients (
n
= 60) who have suffered
a myocardial infarction. Patients who had undergone successful percutaneous coro-
nary intervention (PCI) were randomized to receive bone marrow stem-cell transfer,
injected into the artery supplying the damaged area of the heart, 5 days after PCI or
optimal conventional therapy. After 6 months, improved recovery of LVEF was
more evident in patients who received stem-cell transfer therapy than in patients
treated with standard post-infarction medical care. Mean global LVEF increased by
7% in the stem-cell transfer group compared with 0.7% in the medical group. The
improvement was still evident 6 months after the treatment [
78
] . The authors sug-
gested that autologous bone-marrow cells can be used to enhance left-ventricular
functional recovery in patients after acute myocardial infarction (AMI). However,
larger trials are needed to address the effect of bone-marrow cell transfer on clinical
endpoints such as the incidence of heart failure and survival. In a pilot study (
n
= 4),
Obradovic et al. reported that transplantation of bone marrow-derived progenitor
cells into the infarcted area (3-5 days after infarct) was safe, and feasible, and might
improve myocardial function. Follow-up period for these patients ranged from 30 to
120 days after infarct. This protocol is not based upon mobilization. The reason for
that is the statement that stem cell concentration caused by mobilization in poor
mobilizers is not high enough to ensure efficient homing and engraftment of stem
cells in infarcted area. On the other hand, that non-physiological leukocytosis might
cause occlusion of myocardial arteries. These investigators also concluded that
