AT THE ESC CONGRESS 2016
ROME (FRONTLINE MEDICAL NEWS) – The difference between contemporary drug-eluting coronary stents and bare-metal stents is not very great, a large Norwegian coronary stent trial showed.
Today’s drug-eluting stents (DES), often called second-generation DES, largely do only what they were designed to do, compared with bare-metal stents (BMS): reduce the rate of stent restenosis and the need for target-lesion revascularization.
“The long-term benefit of contemporary DES over BMS was less that expected,” Kaare H. Bønaa, MD, reported at the annual congress of the European Society of Cardiology.
Results from the Norwegian Coronary Stent Trial ( NORSTENT ), run with 9,013 patients, showed that patients who received one or more drug-eluting stents had, during nearly 5 years of follow-up, a 5% absolute drop in target-lesion revascularizations (a 53% relative risk reduction), and a 3.3% reduction in all revascularizations (a 24% relative risk reduction), compared with patients who received bare-metal stents, said Dr. Bønaa.
The results also showed that patients who received DES had a 0.4% reduced rate of stent thrombosis (a 36% relative risk reduction), compared with patients treated with BMS during nearly 5 years of follow-up. All three differences were statistically significant.
But the NORSTENT findings also documented that the patients who received either DES or BMS had virtually identical rates of all-cause deaths and nonfatal myocardial infarctions. And, on average, the two different types of coronary stents produced identical improvements in patients’ quality of life, reported Dr. Bønaa, a professor and researcher in the Clinic for Heart Disease at St. Olav’s University Hospital in Trondheim, Norway.
The study’s primary endpoint was the combined rate of death or nonfatal MI, and so the nonsignificant difference in that outcome between the two study arms meant that, formally, the NORSTENT trial produced a neutral result. Concurrently with his report, the results appeared in an article online (New Engl J Med. 2016 Aug 30. doi: 10.1056/NEJMoa1607991).
“The difference between the two stent types is not as great as we thought. Patients who get DES do not live longer or better” than those who receive BMS, Dr. Bønaa said. “We suggest that both contemporary DES and BMS can be recommended for contemporary revascularization. The results open up use of BMS for certain patients,” such as those scheduled for surgery or patients who cannot tolerate or afford the drugs used for dual antiplatelet therapy following coronary stent placement.
But the designated discussant for the study, Stefan James, MD , insisted that recent-generation DES “should remain recommended over BMS,” particularly the specific DES that underwent testing in randomized trials that used hard clinical endpoints. The 2014 revascularization guidelines of the European Society of Cardiology recommend new-generation DES over BMS, he noted.
In addition, “BMS should not be specifically recommended for patients at high risk of stent thrombosis or for patients who do not tolerate dual-antiplatelet therapy,” said Dr. James, professor of cardiology at Uppsala University in Sweden.
NORSTENT ran at eight centers in Norway during 2008-2011, and enrolled patients either had acute coronary syndrome (71% of those in the study) or stable coronary disease. Patients averaged 63 years old. The trial excluded patients with prior stents or bifurcated coronary lesions. Enrolled patients received, on average, 1.7 stents. The specific stent in each class that patients received was left to the discretion of each operator, and 95% of patients in the DES arm received a second-generation device. All patients in both arms of the study received dual-antiplatelet therapy for 9 months.
The finding that DES cut the rate of revascularization procedures by 3.3%, compared with patients treated with BMS, means that, on average, clinicians would need to treat 30 patients with DES to avoid the need for one additional repeat revascularization procedure that would occur if BMS were used instead.
That number needed to treat of 30 to avoid one repeat revascularization may seem high, but the money saved that way would still counterbalance the incremental cost of a DES over a BMS, which today in Europe would be about 50-100 euros, noted one cardiologist.
If you multiply 30 procedures by 100 extra euros per stent and by an average of 1.7 stents per patient, you may spend 5,100 euros, less than the cost of a repeat revascularization procedure, commented Carlo Di Mario, MD , a professor of cardiology and an interventional cardiologist at Royal Brompton & Harefield Hospitals in London.
NORSTENT received no commercial support. Dr. Bønaa and Dr. Di Mario had no disclosures. Dr. James has been a consultant to Boston Scientific and has received research support from Boston Scientific and Abbott Vascular.
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