Implantation of skeletal myoblasts into scarred myocardium improves symptoms but not heart function

April 1, 2008 By Vijayalakshmi Kunadian MBBS MD MRCP [mailto:vkunadian@perfuse.org]

 SCAI-ACCi2 08-Chicago, IL: The SEISMIC study demonstrates that administration of skeletal myoblasts improves symptoms in patients with heart failure with no effect on left ventricular function and dimensions.

Final results of a phase I/II randomized open-label trial to evaluate intramyocardial autologous skeletal myoblast transplantation in congestive heart failure patients: The SEISMIC (Safety and Effects of Implanted (Autologous) Skeletal Myoblasts (MyoCell) using an Injection Catheter) trial was presented by Dr. Patrick Serruys at the SCAI-i2 summit Annual Scientific Sessions in Chicago today.

The SEISMIC study was a prospective, randomized, multicenter study to assess the safety and efficacy of autologous myoblast implantation (MyoCell™, Bioheart) using a catheter delivery system in patients with congestive heart failure.

The autologous skeletal myoblast cells were obtained from patients' own quadriceps muscles and cultured. These cultured cells (up to 586 ± 193 x109 cells) were implanted into patient’s scarred myocardium using a specialized catheter called the MyoCath® catheter.

The primary endpoints of this study consisted of the incidence of device and procedure related adverse events. The efficacy endpoints consisted of changes in global left ventricular ejection fraction assessed by MUGA scans, changes in the NYHA classification of heart failure and in the distance patients were able to walk during the 6 minute walk test. This study consisted of 47 patients with congestive heart failure randomized in a 2:1 fashion to treatment with autologous cell therapy (n=31) and to the control treatment (n=16). There were 15 instances of sustained arrhythmias in the treatment group and there were 14 instances in the control group. The six minute walk test improved in the cell treatment group compared with the control group, although the result was not significant (60.3 ± 54.1 vs. 0.4 ± 185.7 meters). There was a difference in the improvement in the NYHA class between the treatment and control groups (17.6% vs. 8.3%). More patients in the control group had deterioration of NYHA class (41.7% vs. 5.9%).

At six month follow-up, the LVEF (29.2% vs. 32.9%) and the LVESD (54.5 ± 7.1 vs. 39.4 ± 2.7mm) did not differ between the treatment group and the control groups respectively.

The investigators demonstrated that implantation of skeletal myoblasts into the scarred myocardium is feasible. Although this technique improved symptoms significant benefit was not demonstrated in terms of improvements in the global ejection fraction or left ventricular dimensions at six months.

Source
Late Breaking Clinical Trials Session: SCAI Annual Scientific Sessions in partnership with ACC i2 summit, April 1, 2008 Chicago