European Society of Cardiology Congress: Stem Cells Help Heal Hearts

STOCKHOLM -- Injecting autologous bone marrow stem cells directly into the hearts of patients with chronic heart failure appears to improve ventricular performance, quality of life, and survival, according to an open-label, nonrandomized study.

 

Benefits of the stem cell treatment were apparent within three months -- and persisted for up to five years of follow-up, Bodo-Eckehard Strauer, of Heinrich Heine University of Düsseldorf, Germany, reported at the European Society of Cardiology Congress here.

 

Patients who did not receive a stem cell infusion and remained on optimal medical therapy continued to deteriorate throughout the follow-up period.

There were no side effects, Strauer said in a "Hot Line" session.

 

The findings were reported earlier this year in the European Journal of Heart Failure -- a journal of the ESC -- which led the society to bar Strauer from submitting abstracts for two years. Presenting previously-published data broke the rules for "Hot Line" data.

 

Strauer said at a press briefing that patients with more severe heart failure seem to fare better from the stem cell treatment.

"This therapy has almost no risk. It can only be beneficial in patients. So, in my opinion, it has real clinical importance for the treatment of heart failure," he said.

 

Rob Califf, MD, vice chancellor for research at Duke University, highlighted the limitations of the study in his comments to MedPage Today:

"God gave us two gifts for doing clinical research -- blinding and randomization," Califf said in an interview. "If you have done neither, your data are interesting but not definitive."

 

 

Strauer and his colleagues initially approached 391 patients with chronic heart failure resulting from an acute MI to participate in the study -- 191 agreed to receive an autologous bone marrow stem cell infusion, and 200 declined but agreed to participate as controls. The average period since patients experienced an MI was 8.5 years.

 

Although not randomized, the two groups had similar characteristics at baseline. Mean left ventricular ejection fraction was 29.5% in the treatment group and 36.1% in the control group, but the difference was not statistically significant.

 

All patients continued to receive optimal medical therapy.

 

For the bone marrow cell infusion, the researchers harvested stem cells from the patients' iliac crest. Mononuclear cells were isolated and rinsed with heparinized saline.

 

An average of 66 million stem cells per patient were infused into the infarct-related artery via an angioplasty balloon catheter. Inflation of the balloon simulated an ischemic condition, which prevented back-flow of the cells and provided time for cell migration to the infarct area.

 

At the three-month follow-up, there was significant improvement in left ventricular performance in the treatment group, reflected by improved cardiac index (by 22%), peak oxygen uptake (by 11%), and oxygen pulse (by 6.3%) (P<0.05 for all).

 

Exercise capacity increased by 15.4% from baseline, and left ventricular ejection fraction improved from 29.4% at baseline to 36% at three months (P<0.01 for both).

 

Both end-diastolic and end-systolic volume decreased from baseline in the treatment group (P<0.05 for both).

 

 

The benefits in the treatment group persisted through one and five years.

 

The control group continued to deteriorate through the follow-up points.

 

 

"The reason [for the mortality reduction] may be twofold; namely, a decrease in pump failure and a decrease in severe cardiac arrhythmias," Strauer and his colleagues wrote in their paper.