International Circulation: What is the difference between the Nevo stent and the Cypher stent? What are some of the design innovations?
Prof. Spaulding: There are several innovations. The first innovation is the platform. The platform is a chromium/cobalt platform that is an open-cell thin strut design. Therefore it is very flexible and will be easier to deliver compared to the Cypher stent. The two other new features on the stent are reservoir technology and the use of a biodegradable polymer. The advantage of the biodegradable polymer is that the polymer and the drug are embedded in the stent and therefore there is a reduction of the contact between the polymer and the surface and therefore in animal studies it reduces inflammation and could potentially reduce stent thrombosis in clinical trials. The other new feature is a biodegradable polymer that is completely absorbed after 3~4 months. In animal studies there has been less inflammation and therefore it is potentially a source of a reduction of stent thrombosis. Those are the differences.
International Circulation: What is the difference between the Nevo stent and the Cypher stent? What are some of the design innovations?
Prof. Spaulding: There are several innovations. The first innovation is the platform. The platform is a chromium/cobalt platform that is an open-cell thin strut design. Therefore it is very flexible and will be easier to deliver compared to the Cypher stent. The two other new features on the stent are reservoir technology and the use of a biodegradable polymer. The advantage of the biodegradable polymer is that the polymer and the drug are embedded in the stent and therefore there is a reduction of the contact between the polymer and the surface and therefore in animal studies it reduces inflammation and could potentially reduce stent thrombosis in clinical trials. The other new feature is a biodegradable polymer that is completely absorbed after 3~4 months. In animal studies there has been less inflammation and therefore it is potentially a source of a reduction of stent thrombosis. Those are the differences.
On the other hand, what has remained the same is the use of sirolimus, which is one of the most effective and very well proven drugs, and the kinetics of release of that drug have been very carefully tailored so that the tissue content is similar or even slightly better than what was obtained with Cypher.
International Circulation: What are the advantages of the reservoir technology?
Prof. Spaulding: There are essentially two advantages of the reservoir design. The first advantage is that it reduces the contact between the polymer and the surface and therefore it potentially reduces inflammation. The second thing is that the polymer is in the stent and it will not be damaged when you implant the stent, especially in very heavily calcified tortuous lesions.
Another additional feature for the future is the ability to be able to use these reservoirs to be able to deliver other drugs. Perhaps in the near future we can have stents that not only deliver sirolimus, but also other drugs tailored to the needs of the patient. For example, we can use a drug that can be used in acute myocardial infarction to reduced tissue injury, a drug than reduce thrombus, a drug that can be tailored to diabetic patients, etc.
International Circulation: Why was the Taxus Liberte selected as the comparator stent for this head-to-head trial?
Prof. Spaulding: There was a lot of debate a few years ago when we designed the trial. The Taxus Liberte was the stent that was the most widely used in the world so we decided to compare ourselves to the reference on the market. That is the main reason.
International Circulation: There are going to be follow-on studies as well?
Prof. Spaulding: That is correct. The other studies are the Nevo Res II study, which is a randomized trial, and the comparator will be the Xience V and the Nevo Res III study will be a registry that will be performed in the U.S.
International Circulation: In patients with complex coronary disease and diabetes which one has the best risk-to-benefit ratio, PCI or CABG?
Prof. Spaulding: I work in France and we have just finished four months of difficult debates over the recommendations for reimbursement for drug-eluting stents that we put in for diabetic patients. For diabetic patients with mulitivessel disease CABG is the gold standard and is superior. However, there are many patients with diabetes in whom there is clearly an indication for PCI. Firstly, there are many patients in whom CABG is not possible because they are high-risk patients. Secondly, I believe that a patient with a single vessel disease or two simple lesions on two different arteries can be treated by PCI using drug-eluting stents with the data that we have now.
The message regarding diabetic patients is that they are a very complex group and a very difficult group of patients to treat. When you are treating diabetic patients, you must meet with the surgeon, the non-interventional cardiologist to talk about medical treatment instead of surgery or PCI, and then choose between PCI and CABG based on the evaluation of the Euroscore, which will give you an idea of comorbidities, and the Syntax score, which will give you an idea of the coronary artery lesions. Once you decide to do PCI, it should be performed with the most effective drug-eluting stents.
International Circulation: It appears to be more critical to with diabetic patients that you have a team approach.
Prof. Spaulding. Yes, definitely. It is team approach, especially with diabetic patients. Perhaps there was a lot of focus on the team approach being a team with an interventional cardiologist and a surgeon, but I always feel more comfortable with a non-interventional cardiologist in the group because they can remind us that we can keep many patients on medical treatment for very long and they will do well. For diabetic patients it is also important to bring in specialists that can help you with diabetes.
International Circulation: What is the current status of the use of drug-eluting stents for coronary artery stenosis with distal aneurysms?
Prof. Spaulding: That is a rare situation but there are probably more in China. It is a relatively rare situation right now in France. I look at the angiography and decide on a case by case basis. In cases of huge aneurysms I have very often resorted to surgery because I have felt that it was too dangerous or complicated to put in some coils. In some cases I have put in a stent.