TUESDAY, Jan. 29 (HealthDay News) -- Implanting a stent in a clogged left main coronary artery appeared to give better short-term results than bypass surgery in a Polish study.

But American experts cast some doubt on the clinical value of the finding.

The study, led by cardiologists at the Medical University of Silesia, compared results of surgery versus stenting in 105 patients with serious blockages of the left main coronary artery, which is vital for heart function, because it feeds three other vessels.

There was a significant increase in the heart's blood-pumping ability over the next 12 months in the 52 participants who got the stent implants, but not in the 53 who underwent bypass surgery, said a report in the Feb. 5 issue of the Journal of the American College of Cardiology.

The incidence of major adverse events and the rate of survival was lower in the 30 days following the procedure for stent recipients than for patients who had surgery, the report said, "with a trend toward improved survival" in a two-year follow-up after stent implant.

"One of the limitations of this study is the very small number of patients," said Dr. Edward L. Hannan, assistant dean for research at the State University of New York at Albany, who recently reported at a meeting that surgery tended to be better than stenting for people with blockage of more than one heart artery.

And looking closely at the results, Hannan said he found "no significant difference" between the two methods in the incidence of major adverse events in the longer follow-up.

The Polish results differ from those of one he has done, which he is about to submit to a medical journal for publication, Hannan said. That study, which was not a controlled trial but looked at results reported in clinical practice, found an advantage for surgery over stenting.

But the report has yet to pass the peer review required by medical journals, he cautioned. "No one should trust the results until it has passed peer review," Hannan said.

The surgery-versus-stent question is important for the left main coronary artery, because it is not a blood vessel readily amenable to surgery, Hannan explained. Nevertheless, his research found that surgery "is used much more frequently than angioplasty in current practice, at least 10 times more often. So, we had only a small group of angioplasty patients in our study," he said.

Dr. Howard C. Herrmann, the director of the Interventional Cardiology and Cardiac Catheterization Laboratories at the University of Pennsylvania who has done studies on the subject, found a number of weaknesses in the Polish research, including the small number of patients.

One notable weakness is the relatively short follow-up period, Herrmann explained.

"Their survival time is out to about two years," he said. "Something as important as left main disease might not manifest itself for five years."

Accordingly, older studies that established surgery as the recommended treatment for the condition measured survival at five years or longer, Herrmann noted. "The bottom line from my standpoint is that this study shows that left main stenting is feasible," he said. "I don't think it answers the question about whether it is a better strategy than surgery, which is still considered the standard therapy."

Another report in the same issue of the journal questioned the growing use of a valved stent for aortic stenosis, a condition in which narrowing of a valve reduces the flow of blood from the heart to the aorta and onward to the rest of the body.

The study, by French cardiologists, of 35 cases in which a valved stent was implanted for severe aortic stenosis, found consistent misplacement of the device. "Premature failure of implanted valve stents... might be an important concern in the future," the report warned.

More information

You can learn more about why and how stents are used from the American Heart Association  .

MONDAY, Jan. 28 (HealthDay News) -- Diuretics appear to be as good or better than other blood pressure drugs for treating hypertension in patients with metabolic syndrome, especially black patients, according to a U.S. study.

People with hypertension and metabolic syndrome are at high risk for complications of cardiovascular disease.

Researchers at Case Western Reserve University and University Hospitals Cases Medical Center in Cleveland analyzed data from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT).

It included 42,418 people with hypertension and at least one other risk factor for cardiovascular disease who were randomly assigned to take either the diuretic chlorthalidone (15,255), the calcium channel blocker amlodipine besylate (9,048), the alpha-blocker doxazosin mesylate (9,061), or the ACE inhibitor lisinopril (9,054).

Each drug was used to start treatment, and other drugs were added if necessary to control blood pressure. The majority of patients were followed for an average of 4.9 years, but the alpha-blocker part of the trial was halted after an average of 3.2 years due to increased rates of cardiovascular disease.

Among the patients in the study, 23,077 met the criteria for metabolic syndrome, which is defined as hypertension plus at least two of the following factors: diabetes or pre-diabetes; a body-mass index (BMI) of at least 30; high triglyceride levels; or low levels of high-density lipoprotein ("good" cholesterol).

"No differences were noted among the four treatment groups, regardless of race or metabolic syndrome status for the primary end point (nonfatal myocardial infarction [heart attack] and fatal coronary heart disease)," the study authors wrote.

Among patients with metabolic syndrome, those taking the diuretic had a lower rate of heart failure than those taking the other three drugs. Patients who took the ACE inhibitor and the alpha-blocker also had an increased risk of combined cardiovascular disease.

"The lack of benefit of the agents with the most favorable metabolic profile [i.e., ACE inhibitors and alpha-blockers] was especially marked in black participants with metabolic syndrome," the researchers wrote.

"The magnitude of excess risk of end-stage renal [kidney] disease [70 percent], heart failure [49 percent] and stroke [37 percent] and the increased risk of combined cardiovascular disease and combined coronary heart disease strongly argue against the preference of ACE inhibitors over diuretics as the initial therapy in black patients with metabolic syndrome. Similar high risk was noted for those randomized to the alpha-blocker versus the diuretic."

The researchers concluded that the findings "fail to provide support for the selection of alpha-blockers, ACE inhibitors, or calcium channel blockers over thiazide-type diuretics to prevent cardiovascular or renal outcomes in patients with metabolic syndrome, despite their more favorable metabolic profiles."

The study, which received support from Pfizer Inc., was published in the Jan. 28 issue of the Archives of Internal Medicine.

More information

The American Academy of Family Physicians has more about metabolic syndrome  .

THURSDAY, Jan. 24 (HealthDay News) -- A study of the new anti-clotting drug idraparinux for preventing strokes was stopped early because of excess bleeding, a problem that has plagued the medication.

But the researchers said the trial could open the way to at least limited use of the drug.

The bleeding problem seems to occur primarily in two groups of people -- those over 70 and those with kidney impairment, said study lead author Dr. Harry R. Buller, chairman of the department of vascular medicine at the Academic Medical Center in Amsterdam, the Netherlands.

"We have started a new study in which we have adapted the dose for persons with renal [kidney] impairment," Buller said. "This is another chance to show that this concept is alive."

Idraparinux is one of a number of anti-clotting agents being tested as possible replacements for the current standby warfarin (Coumadin), which is highly effective but difficult to manage, requiring frequent blood tests.

Buller is an idraparinux enthusiast. "Its beauty is twofold," he said. "It uses the body's natural defenses, and it can be given once a week. But much to our regret, particularly in persons over 70 or with some kind of renal impairment, the concentration of the drug builds up, and there is excessive bleeding."

The new study was stopped after enrollment of 4,576 people with atrial fibrillation -- an irregular heartbeat -- after excess bleeding occurred in 19.7 percent of those given weekly injections of idraparinux, compared to 11.3 percent of those taking other anti-clotting agents.

The findings were published in the Jan. 26 issue of The Lancet.

To outside observers, that was a depressing repeat of studies, reported last September, that showed the drug to be effective against deep vein thrombosis and long-term prevention of blood clots but with a high rate of serious bleeding complications.

"This is clearly a setback," said Dr. Alan Go, associate director for clinical research at Kaiser Permanente of Northern California, co-author of an accompanying editorial in the journal.

Go, like other experts in the field, acknowledged that "we are eager to find a replacement for warfarin. It is a remarkably effective drug but challenging to deliver and challenging to take."

Buller said that if all turns out as well as he hopes, idraparinux could be a useful alternative for many people who could get the needed anti-clotting activity with a single weekly injection, while forgoing the constant blood tests required for warfarin users.

"That might lead to some effective agent," Go said. "It's certainly possible, and I wouldn't rule it out. But we would need another large trial to prove it."

Idraparinux is not the only anti-clotting medication in the race to supplant warfarin, Go noted. "At least two oral inhibitors are being tested," he said. "There are different approaches to affecting clotting factors, and there is a very aggressive drive to find something to replace warfarin."

Buller said: "The primary question is, can this drug replace warfarin in preventing stroke? The answer, I think, is yes, but not in subgroups of individuals."

More information

You can learn about the role of anti-clotting drugs in preventing strokes from the Heart Rhythm Society  .

THURSDAY, Jan. 17 (HealthDay News -- Some patients with heart failure may stand to benefit from therapy which modifies the body's immune response.

A study in the Jan. 19 issue of The Lancet found that patients with no history of heart attacks, as well as those in a milder stage of heart failure, had a reduced rate of death and of subsequent hospitalizations with such a treatment.

But the novel therapy is far from hitting hospitals or doctors' offices any time soon, experts said.

"It had absolutely no improvement [in the general study population]," noted Dr. Norbert Moskovits, director of the Heart Failure Program at Maimonides Medical Center in New York City. "The subgroup analysis is more or less a way to come up with a new study. If they show improvements in certain subgroups then next time they can look at that in a larger trial. You cannot draw any conclusions from this, really. It was a very good trial and it still showed nothing."

According to the American Heart Association, some five million Americans have heart failure. "There are half a million new cases each year. It is the number one discharge diagnosis for Medicare patients," Moskovits said. "It's a huge problem, and that's why everyone is looking for a new angle."

Heart failure is commonly treated with drugs, including ACE inhibitors, beta blockers and diuretics. "Most improve patient survival, symptoms and lifestyle," Moskovits said.

Some experts believe that inflammation plays a role in chronic heart failure. Logic would dictate, then, that interfering with the immune system and related inflammatory processes could impact the course of the disease.

But interventions that have targeted specific inflammatory cytokines (signaling chemicals central to the immune system) have not met with much success.

This has led scientists to hypothesize that affecting the immune system more generally might have a benefit.

This study involved more than 2,400 heart failure patients who were randomly assigned to receive non-specific immunomodulation therapy (IMT) or a placebo. They also had left ventricular systolic dysfunction and had undergone hospitalization for heart failure or IV drug therapy in an outpatient setting within the past 12 months.

In this case, IMT involved taking blood from patients with congestive heart failure, exposing the blood to oxidative stress for 20 minutes, then injecting the blood back into the muscle on days 1, 2 and 14, and then every 28 days for at least 22 weeks.

"Certain blood cells in these samples were more or less killed off and, by injecting them, you attenuate the immune response," Moskovits explained. "It's a very cumbersome process."

But after a mean follow-up of more than 10 months, patients in the IMT group showed only an 8 percent reduction in risk of death or hospitalization, which essentially translates into no difference.

However, the results were more impressive in two subgroups of participants: Those with no previous history of heart attack had a 26 percent reduction in risk while those classified with New York Heart Association functional class II heart failure - meaning they had only slight or mild limitations in their activities -- had a 39 percent reduction in risk.

Both of these subgroups were younger and had less severe disease than the entire group of participants.

There was also a trend toward a lowering in C-reactive protein (CRP) concentrations in the IMT arm. CRP is a marker of inflammation and this finding, the authors said, indicates that the concept of treating heart failure with immunomodulation is not yet dead.

But long-term affects also need to be investigated. "By attenuating the immune response, do you subject patients to a higher risk for infections, for cancer?" Moskovits asked. "There are a lot of questions."

Moskovits also pointed out that many therapies for heart failure are counterintuitive. Beta blockers, for instance, were thought for many years to be contraindicated for heart failure. Similarly, a medication to improve heart muscle function in heart failure patients ended up worsening their survival.

The current study was funded by Canadian biotech company Vasogen. Employees of Vasogen were involved with the trial. Authors received an honorarium or travel support or both from the company.

More information

There's more on heart failure at the American Heart Association  .