|Year : 2006 | Volume
| Issue : 4 | Page : 123-125
Drug eluting / bare metal stent controversy in Doha
H. A. Hajar Albinali
Cardiology and Cardiovascular Surgery Department, Doha, Qatar
|Date of Web Publication||17-Jun-2010|
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Albinali HH. Drug eluting / bare metal stent controversy in Doha. Heart Views 2006;7:123-5
Since September 2006, we are witnessing a new war conducted both in cardiology and laymen press. This war concerns a cardiology weapon made of metal - the stent. Which is better: the stent coated with a drug to prevent thrombosis or the plain metal stent?
I do not even know the origin of the word stent. Several English dictionaries struggled with the term and finally came up with a definition: Stent is a device placed in a body structure to provide support and keep the structure open  . I thought that the term "stent" was related to the word "stenosis", which is a narrowing of a vessel, since placement of a stent prevents the stenosis or narrowing. That made sense to a non-English speaking person like me. But it seems that "stent" is a name of a man, who was not even a cardiologist. The dentistry literature states with great pride that the earliest use of the word "stent" was in 1916, when a Dutch plastic surgeon described how he used a dental impression compound in the process of rebuilding a shattered face. The word "stent" derives from the name of an English dentist, Charles Stent (1807-1885), who invented this impression compound in 1856  .
The cardiologists in the cardiology department of Hamad Medical Corporation in Qatar are more concerned about this "stent war" than other deadly wars in our region. The debate about drug eluting stent (DES) and bare metal stent (BMS) comes up in most of our meetings since September 2006.
In fact we were concerned about this problem more that a year ago, when in 2005 we had two patients with stent thrombosis in one week. We reviewed our DES data then. In 2005 we implanted 678 stents. From June 2004 to June 2005, we implanted 414 DES in 412 patients. Ten of the patients with DES had stent thrombosis one to six days after implantation. In nine patients, we were able to document thrombosis with angiography. Two patients admitted that they stopped taking clopidogrel before the event.
In our cardiology department, stenting has unique medical, social and financial impact on our practice, which may be different than any other cardiology department in the world. Our patient demographics consist of Qataris (40%) and non-Qataris (60%). The non-Qataris are from the Indian subcontinent, other East Asian countries, Arab and European countries. The majority of non-Qataris are laborers and low-salaried employees.
In 1985 our department started angioplasty and in 1996, we started stenting with BMS. We started using DES in Oct.16, 2002 shortly after it was introduced in Europe and before it was approved in the USA. We consider our Qatari citizens as privileged patients because we lean towards using DES for any Qatari who needs stenting.
The DES is about three times as expensive as BMS and non-Qataris could not afford it, hence, we made regulations to deal with expatriates who need coronary intervention. Cardiac catheterization, angioplasty, and open heart surgery are practically free for every one living in Qatar, citizen or expatriate. The non-Qatari patients pay for the price of the stent. Such a patient has the following choices to make: DES if he is wealthy, BMS if he is not, or free coronary artery bypass graft (CABG) if indicated. I do not want to give the reader the impression that CABG in Qatar is for the poor. It is still the best choice for certain conditions and its benefit in general is probably more durable that stents.
However, more patients prefer stent over CABG. If stenting is considered as an emergency by the interventional cardiologist such as for acute myocardial infarction, cardiogenic shock, or for treatment of coronary dissection during angioplasty, then any type of stent is provided free to any patient. We have agreement with some stent manufacturers to provide us with a certain percent of stents free for the "poor." For humanitarian reasons, we convinced some charity organizations to pay the cost of stents including DES for poor expatriates when we recommend that such a stent is the best choice for treatment. So, we rarely fail to implant a stent in any patient who needs it despite the cost.
Now, after the storm over DES has blown over us following the release of data that showed an increase in the risk of late stent thrombosis, I wondered who the winners were, the Qataris who had the DES or the poor expatriates who had BMS or CABG. This question reminded me of a local saying "like step-mother oiling". The origin of that saying was that the step mother pours more animal oil over the rice for her children than her step-children. Oil from animal product was considered good for health in the old days in the Arabian Gulf. Now, because of its high cholesterol content, it is considered unhealthy food. So the step-mother harmed her own children with the oil and saved her stepchildren from the harmful effects of oil without knowing. Are we also harming our own citizens with our preference toward DES for them? I am not convinced we are.
The recent concern that the implantation of drug-eluting stents as compared with bare-metal stents may be associated with a small increased risk of late stent thrombosis is not accepted by all authorities in the field. The controversy, the debate, and the war over this issue is still on-going. I am aware that some cardiologists alter their practice by shifting more toward BMS than DES. We have not altered our practice, but we are more cautious and concerned.
Millions of patients with coronary artery disease worldwide have received coronary-artery stents, and a large number of them received DES. No wise physician debates the enormous health benefits of such technical advances in our profession.
Today, March 8, 2007 while I am writing this article, I look into the journals I subscribe to on line, to see any hot update on the stenting controversy to add to this article. I saw in the New England Journal of Medicine of today's date several informative articles on the subject. These articles gave me more information but did not settle the controversy. I will enumerate below their conclusions:
As I stated above, the controversy over DES has made us more cautious. We have regular weekly meetings in our department attended by the cardiologists and cardiac surgeons to make joint decisions on patients with complex CAD lesions. If a decision is needed while the patient is on the table in the catheterization laboratory, we quickly arrange such a meeting in the laboratory. We discourage our interventional cardiologist from jumping to insert DES in complex lesions with high potential for thrombosis such as bifurcation lesion, lesions requiring overlapping stents and small caliber vessel specially in diabetics. We are also cautious with patients who have coexisting medical conditions such as renal failure and diabetes. We rarely stent left main artery in our department. Some of my colleagues are eager to start stenting the left main coronary artery (LMCA) for the last three years, but I succeeded in discouraging them. Our cardiac surgeons are in agreement with me. Today, most of my colleagues are less eager to stent the LMCA.
- In a pooled analysis of data from four trials comparing sirolimus-eluting stents and bare-metal stents, no significant differences were found between the two treatments in rates of death, myocardial infarction, or stent thrombosis  .
- Stent thrombosis after 1 year was more common with both sirolimus-eluting stents and paclitaxel-eluting stents than with bare-metal stents. Both drug-eluting stents were associated with a marked reduction in target-lesion revascularization. There were no significant differences in the cumulative rates of death or myocardial infarction at 4 years  .
- Drug-eluting stents were associated with an increased rate of death, as compared with bare-metal stents. This trend appeared after 6 months, when the risk of death was 0.5 percentage point higher and a composite of death or myocardial infarction was 0.5 to 1.0 percentage point higher per year  .
- The incidence of stent thrombosis did not differ significantly between patients with drug-eluting stents and those with bare-metal stents in randomized clinical trials, although the power to detect small differences in rates was limited  .
- The use of sirolimus-eluting stents does not have a significant effect on overall long-term survival and survival free of myocardial infarction, as compared with bare-metal stents. There is a sustained reduction in the need for re-intervention after the use of sirolimus-eluting stents. The risk of stent thrombosis is at least as great as that seen with bare-metal stents  .
Although many authorities recommend several months of dual antiplatelet therapy after placement of a drug-eluting stent, the optimal duration of such therapy has not yet been precisely determined. I believe that if we are not faced with significant side effect with antiplatelets, we should keep post DES patient on Aspirin and clopidogrel for life. This is what I advise all my patients.
Finally, while our cardiology colleagues in other countries are bombarded with questions and concerns about DES from their patients due to the contradictory headlines about stents in the newspapers these days, we are fortunate that most of our patients are not aware of this controversy. We try our best to provide the best and the safest care to our patient as dictated by our conscience. We follow the fist principle of medicine: "Do no harm".
| References|| |
|1.||Webster's Online Dictionary: |
|2.||Malvin E. Ring et al. How a Dentist's Name Became a Synonym for a Life-saving Device: The Story of Dr. Charles Stent. Journal of the History of Dentistry. Vol. 49, No. 2/July 2001. |
|3.||Christian Spaulding et al. A Pooled Analysis of Data Comparing Sirolimus-Eluting Stents with Bare-Metal Stents. New Eng J Med 2007; 356:989-997. |
|4.||Gregg W. Stone et al. Safety and Efficacy of Sirolimus- and Paclitaxel-Eluting Coronary Stents. New Eng J Med 2007; 356:998-1008. |
|5.||Bo Lagerqvist et al. Long-Term Outcomes with Drug-Eluting Stents versus Bare-Metal Stents in Sweden. New Eng J Med 2007; 356:1009-1019. |
|6.||Laura Mauri et al. Stent Thrombosis in Randomized Clinical Trials of Drug-Eluting Stents. New Eng J Med 2007;356:1020-1029. |
|7.||Adnan Kastrati et al. Analysis of 14 Trials Comparing Sirolimus-Eluting Stents with Bare-Metal Stents. New Eng J Med 2007; 356:1030-1039. |