Friday, June 06, 2008

V-Bloc - new hope or old spin?


Several years ago, they did a study on a device developed, I believe, in Switzerland called the "gastric pacer". Several US Weight loss surgery surgeons jumped on the bandwagon. What this device (implanted in the back - and similar in function to a heart pacemaker) did was send electrical impulses to the vagus nerve of the stomach. No intestines were rearranged, the stomach was not otherwise disturbed and it seemed a really great idea. One surgeon wrote to a listserve "I am testing a device now which will outdate all weight loss surgery in five years!"

I followed the studies on gastric pacing and even interviewed some patients. Unfortunately the results, weightloss-wise, were extremely poor. One patient out of the three studies in one area, lost 70 lbs. One patient lost 100 lbs but became very ill from several things including cancer, partially from the side effects of the device and had to have it removed. The rest in the three studies, either lost very little weight or no weight at all. All of the patients except the two previously mentioned, ended up getting other procedures, either gastric bypass or lap band which they all, down to the man, found not only far more effective with weight loss but also, far more comfortable than the gastric pacer.

But worse yet, this "totally non invasive device" (as it was _heavily_ advertised) had a set of co morbidities of its own, some of which I understand are also true of the heart pacemaker but to a lesser degree.

First, it could travel around in the body causing problems getting where it didn't belong (like heavily inflaming surrounding tissue). The one patient who had to have it removed in an emergency situation, had it travel halfway down her back.

Secondly, the amount of current required to block the vagus nerve turned out to be about 10 times the amount of current required in a heart pacemaker. When the device was working, many patients complained of tingling uncomfortable feelings in their arms.

Third, patients were told it stopped the appetite. But the way it stopped the appetite was to keep the stomach from emptying into the small intestine, a condition well known to GERD patients. What they didn't tell the patients was that if the food just sits in the stomach, it starts to rot and can cause a horrendous case of upset stomach (and burping up, rotten food - I know because I have GERD myself). It can also cause too much stomach acid which splashes into the esophagus and can cause not only heartburn but also a condition of ulcers and sores in the esophagus called "Barrett's Esophagus" which can lead to esophageal cancer - a rather distressing type of cancer.

Fourth, patients were told the battery on the gastric pacer would require changing every 2-9 years which are the statistics on heart pacemakers. But what patients found out was that, because the amount of electrical current required for blocking the vagus nerve, was about 10 times what a heart requires, gastric pacer batteries generally had to be changed every 9 months to a year and that required a small surgery.

And finally, for many patients, disturbing the emptying of the stomach did not cause a great deal of weight loss just like the discomfort (and even stricture) associated with GERD doesn't necessarily cause weight loss either. (Again I can attest to that one - I easily managed a BMI of 44 for years until I found Weight Watchers, even with GERD, and a stricture of the esophagus).

Needless to say, the gastric pacing listserve was closed, the studies of this "utterly hopeful" device having been ended but not without a few lawsuits from sick or upset patients.

But ........

As they say in "infomercials"... but wait! Because the gastric pacer came back in 2005, with a new name, new studies and more heavy advertising! That's right.

In 2005, a small company named EnteroMedics in Minnesota announced that they were working on a type of gastric pacer. The press release included the following:

The company says cutting off the nerve supply may slow down digestion because the stomach doesn't register the food and start the digestive process.
Well, apparently they had begun trials of this device in several cities and like the gastric pacer, they claimed it's totally non invasive. Interestingly enough, the TV blurb on it used a gastric bypass patient to show how great losing weight is and claimed the new gastric pacer (the V-Bloc) "may" work just as well as the gastric bypass.  (Which they soon found out to be not as true - in some studies the weight loss in the controls equaled or exceeded that of the people using the v-Bloc.

So you'd think the second time around, they would have gotten the message.  But apparently they didn't because in Jan 2015, guess what's back!

None other but the V-bloc dolled up with a new name but it's the same old, same old.  They opened a new website for it at: http://www.enteromedics.com/vbloc/

Look quickly because after two or three go-arounds with this device, I suspect the website will be as long lived as the last websites were.  But not until they've sold patients with huge promises of its success.  People cannot remember as far back as 2005, I guess they are reasoning (or hoping?)

The following is from my research in 2005 - I'm quite certain this device has the same issues despite the new name! :)

It was difficult to research the V-bloc. Both the EnteroMedics website and the research study website were very vague about how the device works.

So I called a phone number which stated: "For more information about VBLOC Therapy and the EMPOWER clinical research study, please call the nurse-staffed information line at ......"

I spoke to 2 nurses, one of whom got short with me when I was apparently asking too many questions. She said "really this phone number is merely to identify and qualify patients for the study". To which I answered "well that's NOT what you stated on the website" and I quoted the above. Then I reminded her that as soon as they have advertised the device on TV, then the public has a right to know the details. By the time I spoke to the second nurse (a different lady from the first nurse so they apparently are paying no small fee for having nurses to answer phones!), I had a specific question and was prepared with an answer when she told me the line was just to qualify patients.

I did find out that the chest belt part of V-bloc is the battery pack so apparently one improvement V-Bloc has over the gastric pacer is that to change the battery you don't need the small surgery.

But something else on the EnteroMedics website about what the V-Bloc really does (and this website is not given on the Empower study website either - I had to google it) is a bit unsettling. They admitted that they don't really know how the Vagus nerve interfaces with the appetite but listed the functions of the vagus nerve and it's more than just stopping the peristalsis (the muscular action of the stomach to digest the food and send it to the small bowel). Here is the list of vagus nerve functions which the V-Bloc supposedly stops (from their website) :

The mechanisms responsible for obesity and the role played by the vagal nerves are not yet fully understood. Vagus nerve function appears to play a significant role in enabling multiple mechanisms including:
  • Expansion of the stomach as food enters.
  • Stomach contractions that break food into smaller particles.
  • Release of gastric acid to continue food processing.
  • Emptying of the stomach contents into the small intestine.
  • Secretion of digestive pancreatic enzymes that enable absorption of calories.
  • Sensations of hunger, satisfaction or fullness
In plain terms, the V-bloc not only gives you a horrendous case of indigestion but also can induce a  simulation of "gastroparesis" (stomach not emptying due to partial paralysis), and can interfere with the pancreatic enzymes as well as with stomach acid which will not only affect fat digestion but also protein digestion and vitamin digestion!

In another place on the same website, it stated that the idea for the V-bloc (and probably the gastric pacer also) was that before they had the medication to stop the stomach acid for ulcers, the so called PPIs, they would go in and cut the vagus nerve to help ulcers.

Before the availability of proton pump inhibitors (drugs that reduce the amount of gastric acid released into the stomach for persons with ulcers), surgeons routinely cut the vagus nerves near the stomach to treat ulcers. This procedure is called a "vagotomy." For a period of time following surgery, many of the people who underwent this procedure absorbed fewer calories from fat, lost weight and had decreased appetite.

Notice for a "period of time after surgery". That is, it did not work indefinitely to stop the appetite.

Other than the battery pack (it's carried on a case the size of a compact disc, one nurse told me) worn around the chest (which I suspect might be inconvenient at times) which is an improvement over surgery every nine months to change the battery, it seems the V-bloc is pretty much the "same dog, different fleas" as the devastatingly unsuccessful and risky in its own way, gastric pacer. And something which the TV said has been added i.e. wires in the esophagus (I don't know how accurate the TV report is but since the Enteromedics folks are not giving much information, it's all we have).

The new device might have a smaller battery....

"He who does not study history, is doomed to repeat it" and "doing the same thing repeatedly hoping for a different result is insanity" (said Albert Einstein) so take a tip from those who struggled and suffered with the gastric pacer a few years ago, and consider waiting on the V-Bloc! Its predecessors interfered with digestion as much as the gastric bypass but did not even produce good weight loss results for most people.

At best scenario, the weight loss promised is 15-20 percent of the bodyweight in the first year. Doing the math, 15 percent of 300 lbs is 45 lbs. And likely the real results will be more like 10 percent or less. (as they were with all trials on the gastric pacer).

Surely a horrendous case of indigestion, food rotting in the stomach, heartburn and nausea may slow the appetite but at what price? You can do that without expensive electrical devices and multiple wires implanted in your body.

If you did not come here from the new blog - it's been re-introduced in 2015 ... click here to see the new blog on it...

2 comments:

vesta44 said...

This is another case of something sounding too good to be true (permanent weight loss without horrendous side effects). Any time I see something that says "this will help you lose weight" and involves ANY kind of surgery, I take it with a whole shaker of salt (a grain of salt just isn't enough).
Cynic that I am, I just don't think that they'll ever come up with any way for people to have any kind of significant, permanent weight loss without some kind of awful side effects. But we're supposed to deal with all that because it's just so much better to be thin (even if you're dealing with a shitty life because of the way you got thin) than to be fat, healthy, and happy.

violet_yoshi said...

Rotten food as a weight loss aid you say? I was just imagining Oscar the Grouch trying to create a weight-loss scam, by selling food from his trash can as a sure fire way to put off appetite. And in the end, it wouldn't work, and Oscar would be even more bitter than usual. LoL