Medical Device Daily National Editor

The use of stents to treat blockages of vessels supplying blood and oxygen to the heart was the major, most publicized development in the cardiovascular sector and the device sector as a whole at the end of the 20th century. And it was given a further booster shot at the century's close with the development of drug-eluting stents (DES) that reduced the necessity to redo initial stenting.

The result has been continuing sector skirmishing between drugs and devices, with the balloon/stenting combination (or PCI for percutaneous coronary intervention) frequently presented to patients as a quickly assumed treatment offering the best path to recovery and longer life compared to the use of drugs.

Over time the enthusiasm for stents so enthusiastic for DES, in particular, that the Centers for Medicare & Medicaid Services provided reimbursement for these devices immediately upon FDA approval has eroded as a routine choice, especially with increased emphasis on more careful patient selection of patients for PCI.

That erosion may continue with a just-released report revising previous assumptions.

The researchers conclude that PCI offers no particular advantage over drug therapy for those patients who receive delayed treatment for a myocardial infarction (MI), or heart attack. This category of patients may do just as well on optimal drug therapy, they conclude, though one of the lead researchers, Daniel Mark, MD, is not sure what impact the findings will have on actual interventional practice.

The study appearing in the current issue of the New England Journal of Medicine — reverses the conclusions of earlier analysis of the Occluded Artery Trial (OAT), issued two years ago. That study found that patients who receive delayed treatment for a heart attack did just as well with drugs alone as they do with a drug/PCI combination to open blocked arteries.

Now, further analysis of a smaller number of that population indicates that the drug option is cheaper and that there is no meaningful long-term difference in quality of life between the two strategies.

This is a different study than the SYNTAX trial whose results were reported on in a p. 1 story in last Friday's MDD, but that study which compared the impact of coronary-artery bypass graft surgery and PCI likewise seemed to support alternatives to the use of DES.

Mark, a member of the Outcomes Research Group at the Duke University Clinical Research Group (Durham, North Carolina), and lead study author, said the revision of the earlier finding "is just one more reason to question the use of routine stenting in late-treatment patients when cheaper, less-invasive options are just as effective."

The study population receiving drug/PCI therapy received mostly bare metal stents, just 8% DES devices. But Mark said he did not feel that broader DES use would have made any difference in the conclusions, since the impact of that technology has not been lengthened life but only on reducing the need for redo procedures.

Importantly, the new analysis, besides offering a look at longer-term outcomes, takes a close look at quality-of-life issues and overall costs.

Besides concluding that the use of drugs for these patients costs less, the study found that patients receiving stents enjoyed a no better quality of life, over time, than those treated by drug therapy alone.

The study population consists of patients who began receiving therapy beyond the optimal treatment window for those with arterial blockage, considered within two hours or less following the appearance of first symptoms. But in actual practice one-third of all patients receive initial treatment more than 12 hours or more following the onset of symptoms, the study notes.

Mark said that it has been considered fairly obvious that opening a clogged artery with a stent would benefit these patients, but that cardiologists have been seeking some clear direction that this is, or is not, the case.

With catheterization of these patients, many are found to have a 100% blockage in one of their arteries.

But if a patient survives with this amount of blockage, and is generally stable, with no great angina, what's primarily needed, he said, is "to halt the progress of atherosclerosis that causes these heart attacks in the first place" and can be done with drugs and without stenting.

He added, more succinctly: "You can't make them feel better by messing around with their plumbing."

In the initial OAT trial, Mark and Judith Hochman, MD, of New York University, presented findings from a study of 2,166 patients showing that the two strategies, were equally effective in stable heart attack patients and that the drug/PCI group had some "modest" benefit over the drug-alone group, but not over a longer term.

In their follow-up analysis of 951 patients of the OAT trail, the investigators examined how patients felt about their lives and the cost of the two approaches, including patients who had suffered a heart attack anywhere from three to 28 days prior to enrollment who had a completely blocked artery but who were clinically stable and experiencing no chest pain.

Investigators found that at four months, patients in the drug/PCI group reported less chest pain and scored higher on quality of life measures. But those differences were small and disappeared over time. And by the end of the study, patients in the medical therapy group appeared to be doing just as well as those in the stented group.

Quality-of-life measures included the Duke Activity Status Index (DASI), which reflects cardiac function; the Medical Outcomes Study 36-Item Short-Form, assessing pain, physical limitations, social function and vitality; and the Mental Health Inventory, which assesses psychological well-being. The questionnaires were administered face-to-face or by telephone upon study enrollment, and at four, 12, and 24 months following.

The researchers also compared the costs of the two treatments and the use of healthcare resources among a subgroup of patients in the U.S.

They found that during the first month of treatment, members of the PCI group stayed in the hospital 1.2 days longer than those in the medical group, mostly reflecting longer-time in intensive care.

They also found that the mean cost for hospital and physician care during the first 30 days after starting treatment was $22,859 for the PCI group and $12,683 for the medical therapy group. Cumulative two-year costs were about $7,000 higher in the PCI group.

In summary, Mark said that drug therapy "is one of those cases where less is more. While it may seem that going an extra step in opening up clogged arteries even days after a heart attack, we know that clinically, it doesn't seem to offer the advantages we expected. Coupling that with the higher cost, we now know that adding PCI to standard medical care in opening blocked arteries more than a day after a heart attack is not good value. In an era when the high cost of healthcare is the subject of intense debate, this study offers us one way we can offer high quality care for less money."

Elizabeth Nabel, MD, director of the National Heart, Lung, and Blood Institute, which supported the study, said, "Medical care is not just about immediate results and survival, but it is also about providing good quality of life and minimizing medical costs."

Mark said he could not predict what effect the more recent conclusion would have on actual practice but any change would likely not be quick.

"I've been around my interventional colleagues long enough not to expect any miraculous shift. The process of developing information and having it filtered down to what doctors do on a daily basis takes longer than you would expect."

And he called any change in practice a "wild card" given "current economic chaos [putting] pressures on medical issues in general."

But, he added: "over time, people tend to move toward what we have the best evidence for."

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