Posted on 09/11/2002 7:16:24 AM PDT by NYer
Researchers have created a ``biological pacemaker'' in guinea pigs by slipping a gene into their hearts _ a first step in what could lead to alternatives to the electronic devices now implanted in hundreds of thousands of people each year.
The healthy human heart already contains a small number of specialized ``pacemaker'' cells, which initiate the muscle's beat and determine its rate and rhythm of contraction. But old age or disease can cause the cells to malfunction, and mechanical pacemakers are needed to fix the trouble.
In their study, researchers at Johns Hopkins University used a virus to deliver genes to cells in the guinea pigs' ventricles _ places in the heart where the animals have no natural ``pacemaker'' cells. Three or four days later, some of the animals' ventricle cells had been converted into ``pacemaker'' cells _ able to generate spontaneous, rhythmic electric activity on their own. Researchers speculated that this triggering capacity exists in all regions of the heart, but is suppressed in most cells. ``We effectively lifted the anchor, freeing muscle cells to re-establish ability they last held in the developing embryo,'' said Eduardo Marban, a molecular cardiologist and member of the research team. The study was published in Thursday's issue of the journal Nature.
The researchers said the added gene worked by blocking a mechanism that stifles a heart cell's ability to fire on its own. Marban said that research marks a significant step in what could lead to new treatments for people who require electronic pacemakers. Roughly 250,000 Americans are implanted with the devices each year. ``We can now envision a day when it will be possible to recreate an individual's pacemaker cells or develop hybrid pacemakers, part electronic and part biologic,'' he said.
The study did not aim to find out the effect of the genetically altered cells on the guinea pigs' overall health or survival. Marban's team is conducting a study now on pigs to determine that. He said trials on humans are at least a few years away. David Faxon, chief of cardiology at the University of Chicago, called the study interesting but said it would take further research to show whether the transformed cells would work properly without causing trouble, and give long-lasting help. ``There are lots and lots of things that would have to be done to show serious potential here,'' Faxon said, ``but it's intriguing, no question.''
AP-ES-09-11-02 0749EDT
Best of all ... no batteries needed!
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I've been wrestling with the problem for several years.
When I posted this article, I was hopeful that someone who might potentially benefit, would read it. Thought the procedure is not yet tested on humans, it certainly sounds like a promising alternative to the present "electronic" methods. Good Luck and keep us posted.
Have you had to take anti-coagulants all that time? I'm on Digoxin to regulate the heart rate which actually went back to normal the day after I started it, which tells me it didn't really have anything to do with it. According to the website of the folks who make the Digoxin, it takes about a month for it to work. I'm also taking 5mgs of Warfarin (generic Coumadin) so any pooling blood won't form clots and give me a stroke (I almost had one in the doc's office when he said that!)
The cardio guy is going to do some research to see if I really need to stay on the Warfarin. I haven't developed any side effects from either meds so that's good.
My sincerest sympathy. My daugther is 16. Will keep you and your family in my prayers. Hopefully, a cure will come soon. I just checked the AP Wire again, thinking they might have posted a link to a web site, but there was nothing. If I find one, I'll pass it along to you.
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