The Revitalize Study A record of my experiences and the results of my participating in a cardiac stem cell research project.
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I'd barely woken up in the hospital room after having My Heart Attack, when my cardiologist walked in and asked if I'd be interested in participating in an experimental cardiac stem cells study. Stem cells harvested from my bone marrow could be injected into the damaged area of my heart in the hope that they would attach and grow into new cardiac muscle and/or blood vessels. As a retired research engineer I couldn't resist the temptation to become a lab rat so I immediately volunteered and became test subject number 5 of 30.
The study is being conducted out of the Cedars-Sinia Medical Center in Los Angeles, California, and is called The Revitalize Study. It is a repeat of a successful study in Germany that reported improvements in the cardiac ejection fraction of 7 to 10 points for 30 human test subjects. Since my ejection fraction following the attack was 45, a 7 to 10 point improvement would put me back into the low normal zone for a healthy person. The contact point at Cedars-Sinia is Mr. Robert Godfrey, telephone: 310-423-3977.
The process took a day and a half and was about as uncomfortable as a couple of visits to the dentist to get cavities filled. It began in the morning with my having blood drawn and being fitted with two IVs. Next came an EKG followed by an MRI of my heart with and without a chemical stressor to make my heart work harder. Through the use of images taken before and after the injection of a dye, the MRI provided accurate mappings of which areas of the heart were operating normally and which had died as the result of the attack.
The next step was to have 50 cubic centimeters of bone marrow extracted from my left hip, a process that was uncomfortable, but tolerable. (By the way, bone marrow looks just like blood, though perhaps slightly darker and thicker.)
It takes four hours for the marrow to be centrifuged to collect the stem cells. These turned out to appear to be a few cubic centimeters of golden fluid.
Once that step was completed, a balloon catheter was inserted through my femoral artery up into the same cardiac artery that had been blocked during my attack. The balloon was inflated for three minutes and 1/3 of the stem cells injected. (Inflating the balloon to block the artery insured that the stem cells weren't immediately washed away by circulating blood.) This was repeated two more times with a few minutes of rest between each treatment. The process was almost painless. Toward the end of a three-minute blockage I felt something in my chest similar to swallowing a chunk of apple that got stuck part way down my esophagus.
After that I was requested to remain flat on my back and as motionless as possible for 4 hours to let the opening in the femoral artery heal. The following day I had an echocardiogram (ultrasound), more blood drawn, and after demonstrating that I could walk around safely I was released.
As subject number 5 of 30, I was in the first group of 15 and as such received the stem cells collected from 50 cubic centimeters of bone marrow. The second group of 15 will have twice as much marrow collected and consequently, twice as many stem cells injected into the heart. The goal will be to determine what effect the number of stems cells has.
Throughout the process I was extended first class treatment in every way. I was in constant contact with doctors, not just physician assistants, and was even given a private room. At every turn I felt that I was being treated as an important and valued participant in the study.
Progress and Results:
As part of the study, the health of my heart will be re-evaluated many times during the following year to see how much of the heart regenerated as a result of stem cells growing into new heart muscle or blood vessels. The primary measurement used to determine this will be the ejection fraction, the ratio of the amount of blood pumped out to the body by the left ventricle relative to the maximum amount it holds. This fraction varies from 50 to as high as 64 percent with an average around 55. (Note: the average varies depending on the reference quoted.)
The ejection fraction can be measured with an MRI with an error of plus or minus 2 points or with an echocardiogram (ultrasound) with an accuracy of plus or minus 4 points.
With an echocardiogram the process involves estimating the minimum and maximum area of the left ventricle at two different angles (plains) and using a computer program to calculate the maximum and minimum volumes. The problem is that the images produced by echocardiograms are not razor sharp so there is some question as to where the inside surface of the ventricle is located. Small errors in tracing this surface can lead to large errors in the volume. I do not know if the error of plus or minus 4 points includes tracing errors or if it's just the error associated with the calculations.
The results so far suggest that the stem cell therapy is helping my heart regain a considerable amount of it's function. Immediately after my heart attack my ejection fraction, measured with an MRI, was 47 percent. Three weeks after the stem cell procedure it was measured with an echocardiogram at 50 percent. At five weeks an echocardiogram put it at 51 percent. Although these numbers suggest an improvement they could still be within the error limits. More measurements have to be made to eliminate any systematic problems such as tracing errors.
Also promising is the result from Germany on a 200-subject randomized experiment. This time a number of the subjects went through the entire procedure but were not injected with stem cells to measure the placebo effect. In this study the average person receiving stem cells increased their ejection fraction by 7.5 points over the placebo group.
At the four-month point I went in for my final stress-MRI test to get hard numbers on how much my heart function had improved. While one subject in the study had a 6-point improvement and another a 20-point improvement, mine was only a 5-point increase from 47-percent to 52-percent in the ejection fraction or a 13-percent increase. That puts me back in the low-normal zone. I can live quite well at this level for decades so it's really not bad news. Still, I confess to hoping to be one of the big winners in the study.
The researchers explained that the ejection fraction is not the only measure of my heart's health. They also looked at the heart's vascular system, which also showed some improvement, and the condition of the area of the heart wall that was damaged during the attack. In an echocardiogram (heart ultrasound) dead scar tissue appears white whereas live muscle tissue appears gray. The area of my heart wall that was damaged would normally be mostly white because of the severity of the attack. In my case the only white area was a paper-thin layer on the inside of the heart wall. The rest of it was healthy muscle. They are theorizing that the stem cells helped repair the heart wall, though they can't explain why this didn't translate into a larger increase in the ejection fraction.
Two years after the heart attack I had a second echocardiogram. This one measured an ejection fraction of 55-percent. Additionally, motion analysis of my heart's function showed almost no trace of residual damage. It would seem that the heart has continued to heal, whether as a normal process or from the stem cell therapy could not be determined.
NEW!!! Ultimate Verdict:
In 2009 I got the verdict for the Revitalize Study: it was a failure. While several participants showed significant improvement an equal number realized little or no benefit. The results from harvesting bone marrow stem cells and using them to grow new heart muscles cells was too inconsistent to be a viable treatment. However, the concept was proven to be sound, only the use of marrow stem cells was judged unacceptable. In 2009 Cedars-Sinia began a follow-up study in which a small piece of heart tissue is removed from the subject and used, over a three day process, to grow several tens of millions of heart stem cells, which are then injected into the damaged area as in the Revitalize Study. The hope is that using heart stem cells, which are already primed to grow into heart muscle cells, will produce greater and more consistently positive results.
That ends my participation in the Revitalize Stem Cell study. My days as a lab rat are over. To date mine was the smallest improvement they've seen so on average this is a successful procedure.
The last century could rightly be called the century of immunization because that great medical innovation resulted in the conquest of many illnesses that had plagued mankind for countless millennia. In the same way, the current century could very well be remembered by future generations as the century of the stem cell breakthrough. This technology holds promise to cure so many medical conditions that every effort must be made to support it. I encourage anyone living in southern California who has had a very recent heart attack, or knows of anyone who has, to contact Cedars-Sinia and inquire if they can assist in the new study.
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