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Major Bleed Risk Falls with Bivalirudin vs Heparin en Route to PCI for STEMI: EUROMAX.

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The 30-day risk of death or major bleeding fell significantly in ST-elevation MI (STEMI) patients treated with bivalirudin (Angiomax, the Medicines Company) compared with heparin-based management, both initiated prior to arrival at a hospital for primary PCI, in a large randomized but open-label study[1].

The bivalirudin benefit for that composite end point in the European Ambulance Acute Coronary Syndrome Angiography(EUROMAX) trial was driven by a significant drop in major bleeding, the definition of which excluded bleeding related to CABG surgery.

The heparin-based strategy consisted of either unfractionated heparin (UFH) or the low-molecular-weight heparin enoxaparin(Lovenox, Sanofi). Both groups could receive a GP IIb/IIIa inhibitor provisionally.

EUROMAX was published today in the New England Journal of Medicine with lead author Dr Philippe Gabriel Steg (Hôpital Bichat, Paris, France) to coincide with his presentation of the trial here at TCT 2013 .

http://img.medscape.com/news/2013/ih_131030_Steg_Philippe_Gabriel_TCT2013_120x156.jpg

Dr Philippe Gabriel Steg

Bivalirudin’s 40% primary-end-point relative risk reduction included a >50% drop in risk for non-CABG major bleeding. On the other hand, the relative risk of stent thrombosis with bivalirudin was nearly threefold what was seen in the heparin group, although absolute rates were very low.

At a media briefing on the trial, Steg said the excess stent thromboses with bivalirudin were driven by events in the acute phase, within 24 hours of PCI. And, he observed, they didn’t translate into more reinfarctions or ischemia-driven revascularization.

Still, “acute stent thrombosis . . . while rarely fatal and not outweighing the advantages of bivalirudin, is the only troubling issue with bivalirudin in STEMI, and we do need strategies to reduce this complication,” according to Dr Gregg W Stone (New York-Presbyterian Hospital/Columbia University Medical Center New York, NY), the assigned discussant following Steg’s formal presentation of EUROMAX.

Shades of HORIZONS AMI

The trial’s findings are reminiscent of the HORIZONS AMI trial 30-day outcomes reported about six years ago and covered then by heartwire . That trial, Steg et al observe, preceded some important changes in STEMI management and PCI technique that likely affected bleeding risk, changes that were a part of EUROMAX. These included the expansion of radial-artery PCI access, newer antiplatelet agents, reduced GP-IIb/IIIa-inhibitor use, and progressively earlier initiation of IV anticoagulants.

In the >3600-patient HORIZONS AMI, anticoagulation wasn’t started early during transport. But both it and EUROMAX with its nearly 2200 patients saw a decreased bleeding risk and increased stent-thrombosis risk with bivalirudin compared with heparin. But in contrast to EUROMAX, the earlier trial also showed a reduced risk of cardiac death in bivalirudin patients.

The two studies taken together have more to say than either alone. “I think the results of EUROMAX will heavily impact clinical use of bivalirudin in Europe,” Steg said to heartwire . “The results are very consistent wih HORIZONS AMI, even to the point of the stent-thrombosis signal” and are “reassuring enough to embrace [bivalirudin] in the prehospital setting.” That is, he added, “If you want to. [The EUROMAX results] are not mind-blowing because we don’t see a mortality reduction. But they suggest that the benefits seen in HORIZONS AMI can be extended to the contemporary prehospital setting. “

At the media briefing, Dr Bernard Gersh (Mayo Clinic, Rochester, MN), who wasn’t involved in the trial, said, “It’s not that often that you see trials that really will change clinical practice, and I think this will.”

The Role of Prehospital Diagnosis and Treatment

Gersh also said, “I’ve never seen really anything that suggests that prehospital administration [of anticoagulants] and [STEMI] diagnosis is not beneficial.”

But whether they are achievable in the field varies by country, even within Europe. Interviewed, Steg pointed out that at most participating centers, there were no physicians in the ambulances. It does take some expertise to interpret the ECGs, unless the tracings can be transmitted to a center for remote reading. But, he said, “It’s been shown in other trials if you have good trained paramedics, they do just as well if not better than physicians.”

Also speaking at the briefing as a EUROMAX observer, Dr Philippe Généreux (NewYork-Presbyterian Hospital/Columbia University Medical Center, New York, NY) said prehospital STEMI diagnosis and treatment initiation could make the most difference in countries like Canada, “where there aren’t cath labs on every corner” and it might take 45 to 60 minutes for an ambulance to reach a PCI center.

Prospects for prehospital management in the US seem more remote, observers agreed. Dr James B Hermiller, Jr (St Vincent Hospital/The Heart Center of Indiana, Indianapolis,) said at the briefing, “The barrier to this in the US is very great. It’s difficult just to  get ECGs in the field, let alone administer anticoagulants, but we need to get there because this is very important.”

The Open-Label Randomization

EUROMAX randomized patients at centers in nine European countries presenting within 12 hours of onset of symptoms from electrocardiographically defined STEMI, on an open-label basis, to the bivalirudin or heparin strategies. Treatment was initiated in the ambulance or at a non-PCI hospital with subsequent transport to a PCI center.

For the 1089 patients who received bivalirudin, the drug was started as a 0.75-mg/kg bolus followed by an infusion of 1.75 mg/kg/h continued for at least four hours after PCI. The 1109 control patients received UFH at either 100 IU/g or 60 IU/kg with a GP IIb/IIIa inhibitor or were allowed to have enoxaparin at 0.5 mg/kg. Adjuvant GP IIb/IIIa inhibitors were allowed at physicians’ discretion. All patients received aspirin plus a P2Y12 inhibitor.

Relative Risk (95% CI) for Outcomes, Bivalirudin vs Heparin Strategies for STEMI Initiated During Emergency Transport to Primary PCI

End points

RR (95% CI)

p

30-day death from any cause or non-CABG major bleedinga

0.60 (0.43–0.82)

0.001

30-day death from any cause, reinfarction, or non-CABG major bleeding

0.72 (0.54–0.96)

0.02

Non-CABG major bleeding

0.43 (0.28–0.66)

<0.001

Major bleeding (TIMI definition)

0.62 (0.32–1.20)

0.15

Severe or life-threatening bleeding (GUSTO definition)

0.61 (0.22–1.68)

0.33

Definite stent thrombosisb

2.89 (1.14–7.29)

0.02

a. Primary end point 
b. Academic Research Consortium criteria

No significant differences were seen at 30 days for the composite of death, reinfarction, ischemia-driven revascularization, or stroke, or for any stroke or ischemic stroke. A committee blinded to treatment assignment adjudicated bleeding episodes and clinical events.

As discussant, Stone pointed out that PCI via the radial artery, rather than the femoral artery, was done in only 6% of cases in HORIZONS AMI but in 47% of EUROMAX patients. Some predicted that the greater proportion of radial procedures would lead to a much lower major bleeding rate and make it hard for bivalirudin to show an effect. A EUROMAX subgroup analysis found, however, that the benefits of bivalirudin over the heparin-based strategy were consistent for different kinds of patients, including whether their PCI was by the radial or femoral routes.

“Therefore, bivalirudin is beneficial regardless of the access site, and this is because most bleeding in the STEMI and ACS setting is not access-site related,” he said. It’s the non–access-site bleeds to pose the greater threat to later outcomes. So, he said, “the advantages of bivalirudin are present in patients undergoing radial as well as femoral intervention, and radialists should pay attention to this.”

Stone said EUROMAX raises the question of whether using cangrelor (the Medicines Company) as part of the accompanying antiplatelet therapy might help prevent stent thrombosis with bivalirudin, and that’s being addressed in HORIZONS-AMI-2, which is starting soon.

Scientists Officially Link Processed Foods To Autoimmune Disease.

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The modern diet of processed foods, takeaways and microwave meals could be to blame for a sharp increase in autoimmune diseases such as multiple sclerosis, including alopecia, asthma and eczema.

A team of scientists from Yale University in the U.S and the University of Erlangen-Nuremberg, in Germany, say junk food diets could be partly to blame.

‘This study is the first to indicate that excess refined and processed salt may be one of the environmental factors driving the increased incidence of autoimmune diseases,’ they said.

Junk foods at fast food restaurants as well as processed foods at grocery retailers represent the largest sources of sodium intake from refined salts.

The Canadian Medical Association Journal sent out an international team of researchers to compare the salt content of 2,124 items from fast food establishments such as Burger King, Domino’s Pizza, Kentucky Fried Chicken, McDonald’s, Pizza Hut and Subway. They found that the average salt content varied between companies and between the same products sold in different countries.

U.S. fast foods are often more than twice as salt-laden as those of other countries. While government-led public health campaigns and legislation efforts have reduced refined salt levels in many countries, the U.S. government has been reluctant to press the issue. That’s left fast-food companies free to go salt crazy, says Norm Campbell, M.D., one of the study authors and a blood-pressure specialist at the University of Calgary.

Many low-fat foods rely on salt–and lots of it–for their flavor. One packet of KFC’s Marzetti Light Italian Dressing might only have 15 calories and 0.5 grams fat, but it also has 510 mg sodium–about 1.5 times as much as one Original Recipe chicken drumstick. (Feel like you’re having too much of a good thing? You probably are.

Bread is the No. 1 source of refined salt consumption in the American diet, according to the Centers for Disease Control and Prevention. Just one 6-inch Roasted Garlic loaf from Subway–just the bread, no meat, no cheeses, no nothing–has 1,260 mg sodium, about as much as 14 strips of bacon.

How Refined Salt Causes Autoimmune Disease

The team from Yale University studied the role of T helper cells in the body. These activate and ‘help’ other cells to fight dangerous pathogens such as bacteria or viruses and battle infections.

Previous research suggests that a subset of these cells – known as Th17 cells – also play an important role in the development of autoimmune diseases.

In the latest study, scientists discovered that exposing these cells in a lab to a table salt solution made them act more ‘aggressively.’

They found that mice fed a diet high in refined salts saw a dramatic increase in the number of Th17 cells in their nervous systems that promoted inflammation.

They were also more likely to develop a severe form of a disease associated with multiple sclerosis in humans.

The scientists then conducted a closer examination of these effects at a molecular level.

Laboratory tests revealed that salt exposure increased the levels of cytokines released by Th17 cells 10 times more than usual. Cytokines are proteins used to pass messages between cells.

Study co-author Ralf Linker, from the University of Erlangen-Nuremberg, said: ‘These findings are an important contribution to the understanding of multiple sclerosis and may offer new targets for a better treatment of the disease, for which at present there is no cure.’

It develops when the immune system mistakes the myelin that surrounds the nerve fibres in the brain and spinal cord for a foreign body.

It strips the myelin off the nerves fibres, which disrupts messages passed between the brain and body causing problems with speech, vision and balance.

Another of the study’s authors, Professor David Hafler, from Yale University, said that nature had clearly not intended for the immune system to attack its host body, so he expected that an external factor was playing a part.

He said: ‘These are not diseases of bad genes alone or diseases caused by the environment, but diseases of a bad interaction between genes and the environment.

‘Humans were genetically selected for conditions in sub-Saharan Africa, where there was no salt. It’s one of the reasons that having a particular gene may make African Americans much more sensitive to salt.
‘Today, Western diets all have high salt content and that has led to increase in hypertension and perhaps autoimmune disease as well.’

The team next plan to study the role that Th17 cells play in autoimmune conditions that affect the skin.
‘It would be interesting to find out if patients with psoriasis can alleviate their symptoms by reducing their salt intake,’ they said.

‘However, the development of autoimmune diseases is a very complex process which depends on many genetic and environmental factors.’

Stick to Good Salts

Refined, processed and bleached salts are the problem. Salt is critical to our health and is the most readily available nonmetallic mineral in the world. Our bodies are not designed to processed refined sodium chloride since it has no nutritional value. However, when a salt is filled with dozens of minerals such as in rose-coloured crystals of Himalayan rock salt or the grey texture of Celtic salt, our bodies benefit tremendously for their incorporation into our diet.

“These mineral salts are identical to the elements of which our bodies have been built and were originally found in the primal ocean from where life originated,” argues Dr Barbara Hendel, researcher and co-author of Water & Salt, The Essence of Life. “We have salty tears and salty perspiration. The chemical and mineral composition of our blood and body fluids are similar to sea water. From the beginning of life, as unborn babies, we are encased in a sack of salty fluid.”

“In water, salt dissolves into mineral ions,” explains Dr Hendel. “These conduct electrical nerve impulses that drive muscle movement and thought processes. Just the simple act of drinking a glass of water requires millions of instructions that come from mineral ions. They’re also needed to balance PH levels in the body.”
Mineral salts, she says, are healthy because they give your body the variety of mineral ions needed to balance its functions, remain healthy and heal. These healing properties have long been recognised in central Europe. At Wieliczka in Poland, a hospital has been carved in a salt mountain. Asthmatics and patients with lung disease and allergies find that breathing air in the saline underground chambers helps improve symptoms in 90 per cent of cases.

Dr Hendel believes too few minerals, rather than too much salt, may be to blame for health problems. It’s a view that is echoed by other academics such as David McCarron, of Oregon Health Sciences University in the US.

He says salt has always been part of the human diet, but what has changed is the mineral content of our food. Instead of eating food high in minerals, such as nuts, fruit and vegetables, people are filling themselves up with “mineral empty” processed food and fizzy drinks.

Source: preventdisease.com