On Rehabilitating Drug-Eluting Stents

In a post appearing today on theHeart.org (registration required), cardiologists Allen Jeremias and Ajay Kirtane discuss an article they've written for the Annals of Internal Medicine regarding the safety of drug-eluting stents (DES).

As readers of this site know, the last couple of years have been tough for proponents of DES (and the doctors who insert them). The problem is that a long-term risk of sudden occlusion of the coronary artery has been identified with with these stents. These occlusions are produced by the sudden formation of blood clots (thrombosis) at the site of the stent. Sudden blockage of a coronary artery, of course, can have catastrophic results including heart attack and sudden death. Because of this now-widely acknowledged risk, many cardiologists are insisting that patients treated with DES remain on Plavix (clopidogrel), a powerful blood thinner, for at least a year, and possibly forever.

Jeremias and Kirtane's new article reviews the currently available information regarding the risk with DES. They conclude that, while there is indeed an increased risk of late thrombosis with DES, that risk is statstically low, and overall, latest evidence shows there are no more deaths or heart attacks with DES than with bare metal stents. Further, they note, the need for additional invasive procedures (such as re-stenting or bypass surgery) is significantly reduced when DES are used instead of bare metal stents. So overall, they conclude that (in appropriately selected patients) there is a net benefit to DES.

The purpose of their Annals article, they say, is to make sure the public and non-cardiologists realize that the latest evidence indicates that the benefits of DES outweigh the risks. Indeed, they published their article in a general medical journal because "this message really needs to come out to the general medical practitioner."

DrRich Comments:

The way it's shaping up is this: DES reduces the incidence of the "standard" form of restenosis (i.e., restenosis that's usually reasonably gradual in onset) that is seen with bare metal stents, and therefore reduces the need for re-stenting and bypass surgery. One of the prices that is paid for this benefit, however, is a small incidence in late, sudden, catastrophic thrombosis of the coronary artery that, at best, causes a heart attack, and that, at worst, is suddenly fatal. (In other words, when this form of "restenosis" occurs, there's generally no opportunity for re-stenting or bypass surgery.) When you add all the numbers together, the results are pretty much as Jeremias and Kirtane describe them. There does indeed appear to be a net statistical benefit for DES.

DES have gotten so much bad press over the past couple of years that the growth of both the stent industry, and of interventional cardiologists' practices, have stalled. So the Annals article, the authors forthrightly tell us, is aimed at reassuring non-cardiologists and the public that the water's safe again; so by all means, go ahead with DES. And perhaps the article will have that effect. (Personally, I find the article a bit turgid and perhaps even equivocal, even for an academic paper. To my mind it's certainly not the sort of writing that is likely to lead to widespread epiphanies. But maybe that's just me. The article is online, though - here, read it yourself.)

But even with the encouraging news about DES, it is important for patients whose doctors wish to give them DES to ask two questions before agreeing to this course of treatment.

First, "Do I really need a stent?" Recently, the COURAGE trial showed that for patients with stable angina, outcomes were similar in patients receiving either aggressive drug therapy or stents. So make sure the decision to place a stent of either variety is a carefully considered one.

And second, "If you give me a DES, how are we going to manage the Plavix?" The stent itself is only half of the question. Long-term Plavix therapy - now thought to be required whenever a DES is placed - is not benign. Indeed, trauma or surgery while on Plavix can have devastating consequences. Some cardiologists refuse to allow their DES patients to stop Plavix even long enough to have elective surgery, which obviously places the patient in an untenable position. So before agreeing to any therapy that requires long-term Plavix, discuss with your doctor what the plan will be if, in 8 months, you need gallbladder surgery or a breast biopsy. If he/she doesn't give you a straightforward answer, think long and hard before you let him/her place a DES.

If interventional cardiologists like Jeremias and Kirtane wish to jump-start the DES market, one thing they're going to have to do is address the Plavix question in a straightforward manner. Too many patients are being caught between a cardiologist who absolutely refuses to allow them to stop Plavix for even a few days, and a surgeon who absolutely refuses to do needed surgery in a patient taking Plavix. The Annals article, unfortunately, continues to skate on this very common, very practical, and very difficult question.