Correspondence
Coronary-Artery Stents
N Engl J Med 2006; 354:2076-2078May 11, 2006
- Article
To the Editor:
I am troubled by the universal enthusiasm displayed by interventional cardiologists for coronary-artery stenting — stent mania. As mentioned by Serruys et al. in their excellent review (Feb. 2 issue),1 “stenting [with bare metal stents] reduces restenosis and repeated intervention, but does not reduce mortality or myocardial infarction,” as compared with angioplasty alone. This failure to improve prognosis is also true for drug-eluting stents. However, life-threatening, in-stent thrombosis does present a serious early and late risk — and one that increases greatly if antiplatelet drugs are stopped. Antiplatelet regimens that are required in such cases not only are expensive but pose a major dilemma if noncardiac surgery or procedures become necessary. Systemic hypersensitivity reactions to stents, the improper positioning or dislodgment of stents, and delayed restenosis have been reported. What else may be in the offing? For angina, I believe I would prefer to have just plain old balloon angioplasty, rather than a bare metal or drug-eluting stent, with their uncertain future risk, irrevocably stuffed into my coronary artery. Because restenosis usually presents with angina, the culprit area can be successfully redilated.
1 ReferencesMark E. Silverman, M.D.
Fuqua Heart Center, Atlanta, GA 30309
marksil@comcast.net 1
Serruys PW ,Kutryk MJB ,Ong ATL . Coronary-artery stents. N Engl J Med 2006;354:483-495
Full Text | Web of Science | Medline
To the Editor:
Serruys et al. did not cite the recently initiated Research on Adverse Drug Events and Reports (RADAR) project,1 which reported that 262 patients had allergic reactions after the implantation of drug-eluting stents. Data for the RADAR study came from the Manufacturer and User Facility Device Experience center of the Food and Drug Administration. Reactions were rash, hives, itching, dyspnea, fever, eosinophilia, and increased levels of IgE antibodies. Fatal in-stent thrombosis developed in four patients. Hypersensitivity to drug-eluting stents appears to be a real risk.2
Acute coronary thrombosis that is associated with hypersensitivity reactions3 occurs through the action of inflammatory mediators released from interacting mast cells, lymphocytes, and macrophages. Macrophages, lymphocytes, and eosinophils were found in the intima, media, and adventitia of a patient who died from in-stent thrombosis.1 Current components of drug-eluting stents include polymer coatings, the drugs sirolimus and paclitaxel, and metals — all of which can induce this syndrome.4
Therefore, one can make a good case for careful history taking regarding allergies, skin testing, monitoring of the levels of inflammatory mediators, and the use of corticosteroids and mast-cell stabilizers in patients with atopic allergy who receive drug-eluting stents.
4 ReferencesNicholas G. Kounis, M.D.
George N. Kounis, M.D.
Patras Highest Institute of Education and Technology, 26221 Patras, Greece
ngkounis@otenet.gr Sophia N. Kouni, M.Sc.
Technological Educational Institute of Patras, 26221 Patras, Greece1
Nebeker JR ,Virmani R ,Bennett CL , et al. Hypersensitivity cases associated with drug-eluting coronary stents: a review of available cases from the Research on Adverse Drug Events and Reports (RADAR) project. J Am Coll Cardiol 2006;47:175-181
CrossRef | Web of Science | Medline2
Azarbal B ,Currier JW . Allergic reactions after the implantation of drug-eluting stents: is it the pill or the polymer? J Am Coll Cardiol 2006;47:182-183
CrossRef | Web of Science | Medline3
Nikolaidis LA ,Kounis NG ,Gradman AH . Allergic angina and allergic myocardial infarction: a new twist on an old syndrome. Can J Cardiol 2002;18:508-511
Web of Science | Medline4
Kounis NG. Kounis syndrome (allergic angina and allergic myocardial infarction): a natural paradigm? Int J Cardiol (in press).
To the Editor:
In their 13-page review, Serruys et al. devote only two short paragraphs (under “Unresolved Issues”) to the important but erroneous suggestion that rates of survival are similar with stenting and bypass surgery among patients with multivessel disease and those with stenosis of a left main coronary artery. This inference is disingenuous when the best real-world evidence strongly favors a substantial survival advantage and a markedly reduced need for reintervention with bypass surgery.1-3
Their conclusion is based on 15 randomized trials, including the Arterial Revascularization Therapies Study (ARTS), all of which “manufactured” an apparently equivalent survival for both interventions by including only patients with a very low risk of severe disease and systematically excluding those with severe disease,4 who gain a proven prognostic benefit from surgery.5 Extension of the trial results to the wider population has distorted clinical practice and effectively prevented patients from being able to make appropriately informed choices about the best treatment.4 In a similar manner, considering that the senior author's group recently wrote that disappointing results with drug-eluting stents in left main coronary-artery stenosis favored surgery as the best option, the call for a randomized trial with stents hardly seems appropriate or justifiable.5
5 ReferencesDavid P. Taggart, M.D.
University of Oxford, Oxford OX3 9DU, United Kingdom
david.taggart@orh. nhs. uk 1
Brener SJ ,Lytle BW ,Casserly IP ,Schneider JP ,Topol EJ ,Lauer MS . Propensity analysis of long-term survival after surgical or percutaneous revascularization in patients with multivessel coronary artery disease and high-risk features. Circulation 2004;109:2290-2295
CrossRef | Web of Science | Medline2
Hannan EL ,Racz MJ ,Walford G , et al. Long-term outcomes of coronary-artery bypass grafting versus stent implantation. N Engl J Med 2005;352:2174-2183
Full Text | Web of Science | Medline3
Valgimigli M ,van Mieghem CA ,Ong AT , et al. Short- and long-term clinical outcome after drug-eluting stent implantation for the percutaneous treatment of left main coronary artery disease: insights from the Rapamycin-Eluting and Taxus Stent Evaluated At Rotterdam Cardiology Hospital registries (RESEARCH and T-SEARCH). Circulation 2005;111:1383-1389
CrossRef | Web of Science | Medline4
Taggart DP . Surgery is the best intervention for severe coronary artery disease. BMJ 2005;330:785-786
CrossRef | Web of Science | Medline5
Yusuf S ,Zucker D ,Peduzzi P , et al. Effect of coronary artery bypass graft surgery on survival: overview of 10-year-results from randomised trials by the Coronary Artery Bypass Graft Surgery Trialists Collaboration. Lancet 1994;344:563-570
CrossRef | Web of Science | Medline
Author/Editor Response
Dr. Silverman may prefer balloon angioplasty for his coronary stenosis, but given the robust body of evidence available in 2006, the vast majority of patients and their treating physicians would probably overwhelmingly opt for stenting over balloon angioplasty. It is important to remember that all three revascularization procedures carry a risk of closure: graft occlusion in the case of coronary-artery bypass surgery, subacute vessel closure in balloon angioplasty, and stent thrombosis in coronary stenting. With current therapies, the incidence of stent thrombosis is the lowest among the three. The use of long-term aspirin therapy carries a class 1 indication with level A evidence in patients with coronary artery disease. Therefore, after stent implantation, it is imperative that all patients should continue to receive aspirin for their entire lives.
The article by Nebeker et al. that was cited by Dr. Kounis and colleagues was published after our article was accepted. It adds to our ever-expanding knowledge of drug-eluting stents. However, contrary to the observations of Dr. Kounis and colleagues, Nebeker et al. report that an allergic reaction to a drug-eluting device was certain in 4 patients and probable in 13 others. No incidence of such a reaction could be reported because of the inherent bias of the population, but such an incidence was probably low. We are unsure about the scientific validity of a blanket recommendation of routine skin testing and so forth without sufficient scientific indications.
The gold standard in trial design for the comparison between two strategies is the prospective, randomized, controlled trial. In the five-year follow-up to the ARTS trial, we demonstrated that survival was equivalent in patients who were randomly assigned to undergo either surgery or stenting for multivessel disease. Propensity-matched or adjusted retrospective comparisons, by definition, contain differences in group characteristics, since treatment choice is often dictated by measurable variables (risk factors and coexisting illnesses) and unmeasurable variables (emotional factors, social conditions, and the preference of the patient or physician). No adjustment, however meticulous, can correct for these multiple and often subtle differences. On the other hand, a well-designed randomized, controlled trial, through its design, obviates such a need.
There are two pivotal randomized, controlled trials in progress comparing bypass surgery with the use of drug-eluting stents. They are the Future Revascularization Evaluation in Patients with Diabetes Mellitus — Optimal Management of Multivessel Disease (FREEDOM) trial and the Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) trial. Both trials are designed to address the treatment of patients at highest risk: those with multivessel disease who have diabetes (FREEDOM) and those with disease of the left main stem or three-vessel disease (SYNTAX). Surrounding the randomized groups in both these trials will be preference registries for both coronary-artery bypass grafting and stenting to make possible capture and enrollment of patients not suitable for randomization. These trials are for “all comers,” with sites that are committed to the enrollment of consecutive patients into either the randomized groups or the preference groups. The future results of both trials will provide the necessary answers with respect to the most appropriate revascularization strategy.
Patrick W. Serruys, M.D., Ph.D.
Andrew T.L. Ong, M.B., B.S.
Thoraxcenter, 3015 GD Rotterdam, the Netherlands- Citing Articles (5)
Citing Articles
1
Nicholas G. Kounis, Sotiris Giannopoulos, Grigorios G. Tsigkas, John Goudevenos. (2011) Eosinophilic responses to stent implantation and the risk of Kounis hypersensitivity associated coronary syndrome. International Journal of Cardiology
CrossRef2
Gladius Lewis. (2008) Materials, fluid dynamics, and solid mechanics aspects of coronary artery stents: A state‐of‐the‐art review. Journal of Biomedical Materials Research Part B: Applied Biomaterials 86B:2, 569-590
CrossRef3
George N. Kounis, George Hahalis, George D. Soufras, Andreas Mazarakis, Constantinos Niarchos, Nicholas G. Kounis. (2008) Kounis syndrome and simultaneous multivessel acute coronary syndromes after successful drug-eluting stent implantation. International Journal of Cardiology 127:1, 146-148
CrossRef4
David P Taggart. (2007) Coronary artery bypass graft vs. percutaneous coronary angioplasty: CABG on the rebound?. Current Opinion in Cardiology 22:6, 517-523
CrossRef5
NICHOLAS G. KOUNIS, GEORGE HAHALIS, THEOHARIS C. THEOHARIDES. (2007) Coronary Stents, Hypersensitivity Reactions, and the Kounis Syndrome. Journal of Interventional Cardiology 20:5, 314-323
CrossRef
