You’d think after about 20 years, questions about the efficacy of stents would be settled. You’d be wrong.
Even as players large and small scramble to get the first bioabsorbable product to market, there are conflicting reports about the best way to treat heart disease — devices or drugs?
First, there’s recent news about the third wave of stent technology, bioabsorbable stents that dissolve after implantation. According to a study in the venerable British medical journal The Lancet, two years after implantation patients who received bioabsorbable stents showed almost complete restoration of the stented portion of the blood vessel.
According to European Society of Cardiology spokesman Franz Eberli of the University Hospital Zurich, the two-year examination of 30 patients given bioabsorbable everolimus coronary stents showed smooth coronary vessel walls and nearly total absorption of the stents.
Patients also showed a lack of in-stent thrombosis, a common problem with bare and drug-eluting stents.
But the bioabsorbable stents were less effective at keeping coronary vessel walls fully open, most likely because they exert less radial force than other stent designs. In a prepared statement, Eberli said second-generation versions of the devices will likely address this issue:
“The fact that vasomotion (the ability to undergo vasodilation and vasoconstriction) was restored in response to vasoactive agents in the stented vessel segment was a really good sign. It shows that after two years the physiological function of the stented part of the vessel has been almost completely restored and that patients will not get any symptoms of angina or limitations in physical activity.”
But, he cautioned, with only 30 patients with a single coronary lesion (the most straightforward condition requiring treatment with a stent), the study is too small to prove that the technology is safe for widespread use.
And even before they hit the market, there are questions about whether angioplasty/stenting is the way to go at all. Another recent Lancet study of the treatment of non-acute heart problems suggests that drug therapies are more effective than invasive procedures:
“Treating people with non-acute heart problems should start with drug therapy, not invasive techniques such as angioplasty or implanting stents, because there is no difference between the two approaches in outcomes, a new study finds. …”
“‘In the short run, angioplasty procedures among stable patients can improve symptoms but are not lifesaving,’ said Dr. David J. Moliterno, chief of cardiovascular medicine at the University of Kentucky’s Gill Heart Institute.
“‘To improve life span takes more than a few minutes in the catheterization laboratory,’ he said. ‘Rather, a lifetime of change is usually needed.'”
The meta-study of 61 clinical trials involving 25,388 patients by Tufts Medical Center’s Dr. Thomas Trikalinos found that angioplasty and either bare-metal or drug-coated stents did not result in fewer deaths or heart attacks than medical therapy.
That’s because your doctor’s tiresome advice to eat better and get more exercise is right:
“‘The reason for the similar outcome is likely that these hardest endpoints occur at a relatively low rate among stable cardiac patients when followed for a short period of time and are more affected by risk factor and lifestyle modifications,’ Moliterno said.”
So get the salad, not the steak. Unless you’re European:
“European cardiologists called on Friday for greater use of stents, in a move that could boost demand for the tiny scaffolds that are used to prop open clogged arteries.”