September 28th, 2010
ICD Software Upgrade Can Reduce Inappropriate Shocks from Faulty Leads
Larry Husten, PHD
A software upgrade for ICDs can help reduce inappropriate shocks, according to a study published online in Circulation. Following reports of high failure rates of Sprint Fidelis defibrillation leads, a software program known as a lead-integrity alert (LIA) was developed for download into previously implanted ICDs.
Charles Swerdlow and colleagues compared 213 ICD patients who received the LIA with 213 patients who did not. More than one inappropriate shock occurred in 38% of LIA recipients versus 70% of patients without the LIA software. “Hundreds of patients have been saved from unnecessary shocks by software that is safe and can be painlessly downloaded in one minute during a standard defibrillator check,” said Swerdlow, in an AHA press release.
Swerdlow noted that one year after the release of the software upgrade, “30% of patients undergoing remote monitoring had not had the software downloaded.”
September 27th, 2010
Carotid Endarterectomy Still Beneficial At 10 Years
Larry Husten, PHD
Carotid endarterectomy (CEA) in asymptomatic patients under 75 years of age reduces the long-term risk of stroke, according to 10-year results from the Asymptomatic Carotid Surgery Trial (ACST), published in the Lancet. The ACST investigators randomized 3120 asymptomatic patients to immediate CEA or to indefinite deferral of CEA. At 5 years, CEA had been performed on 92.1% of patients in the immediate CEA group compared to 16.5% in the deferral group. At 10 years, the net risk (death or stroke within 30 days and non-perioperative stroke) was 13.4% % in the immediate CEA group versus 17.9% in the deferral group. The relative reduction in risk was independent of whether the patients were taking lipid-lowering therapy, but the absolute risk of stroke was lower in patients on lipid-lowering therapy.
The authors concluded that CEA is most effective in patients with a long life expectancy, “because the potential long-term benefits of CEA are sharply curtailed in those who have less than 10 years of life expectancy… For otherwise healthy men and women younger than 75 years… the results from this trial suggest net benefit from CEA, as long as perioperative risks remain low.”
September 27th, 2010
Xience V Holds Its Own With Sirolimus-Eluting Stents
Larry Husten, PHD
In the trials presented on Thursday at TCT, the everolimus-eluting Xience V stent (EES) proved superior to the paclitaxel-eluting Taxus stent at 2 years. But, as Gregg Stone discussed here recently, a more formidable comparator for EES are the sirolimus-eluting stents (SES). Two trials presented on Friday demonstrated that EES are comparable in efficacy to SES.
Robert Byrne presented the two-year outcomes of the ISAR-TEST 4 trial comparing the EES and the SES in 1304 patients. He reported that the rate of cardiac death, target vessel MI, or TLR was 18.8% with SES versus 16% with EES, a difference that did not achieve statistical significance. Byrne concluded that the stents “provide comparable clinical outcomes out to 2 years.”
In the SORT OUT IV trial presented by Lisette Okkels Jensen, nearly 2800 patients were randomized to EES or SES. The primary endpoint — major adverse cardiac events — was reached in 4.9% of the EES group and 5.2% of the SES group, therefore meeting the predefined criteria for non-inferiority.
September 27th, 2010
Promising Results for New DES in Peripheral Disease
Larry Husten, PHD
A new drug-eluting stent designed to treat peripheral disease showed promising results in the largest trial yet of endovascular treatment in this population. The 12-month results of the Zilver PTX randomized trial comparing a novel paclitaxel-eluting stent versus balloon angioplasty and bare-metal stenting in patients with symptomatic above-the-knee femoropopliteal artery disease were presented at TCT2010 by Michael Dake.
Patients (n=479) were randomized to either the Zilver PTX or percutaneous transluminal angioplasty (PTA). In addition, for the patients who had suboptimal results with PTA, a second randomization was performed, to either the bare Zilver stent or the Zilver PTX stent.
The rate of event-free survival at one year was 90.4% in the Zilver PTX group versus 82.6% in the PTA group. The patency rate at one year was 83.1% for the Zilver PTX versus 67% for the standard care group who received PTA with provisional bare metal stenting. In the second randomization, the patency rate was significantly higher in the Zilver PTX group than in the bare Zilver group (89.9% versus 73%), resulting in a dramatic 63% reduction in the 12-month restenosis rate.
September 26th, 2010
Avandia: Lessons Learned and Unanswered Questions
Harlan M. Krumholz, MD, SM
The following is republished from Pharmalot, a widely read site that provides commentary on the pharmaceutical industry and related litigation.
What should we make of the decisions on Avandia yesterday? There remains some controversy about the risk, but the concerns were sufficient, given the therapeutic alternatives, to bring about action. The Europeans decided to suspend sales of the drug, and the Americans opted to leave it on the market, albeit with tough restrictions. The company has announced it will no longer promote the drug, and the practical result in Europe and the US may be a lot more similar than the decisions at first appear. Usage will stop in Europe, and new use should virtually stop here. But is the story over? There are at least some issues worthy of consideration as we get to the end of the tale.
1. The Delay to Judgment: If the drug has a probable hazard that is sufficient to require severe restrictions in the US and suspension in Europe, then why did it take so long to reach a decision? The basic information about the drug has been around for years. No new trials indicated great risk — all we know could have been known a while ago. Moreover, why did it take more than two months in the US after the FDA advisory committee met (last July) and the vote was clearly signaling a concern to take action? In the interim, sales have been continuing, and patients may have assumed that no news is good news about the drug. We need a more-responsive FDA, one that moves with all deliberate speed — but with speed — particularly when there are life-threatening safety concerns.
And by the way, Avandia has been on the market since 1999 — aside from the recent delays — why did it take so long to assemble all the evidence? And what would have happened if Steve Nissen (who authored the 2007 meta-analysis declaring higher cardiovascular risk with Avandia) had not found the Avandia trial data? And what would have happened if (former New York Attorney General) Elliot Spitzer had not included the sharing of trial data in the settlement with Glaxo over Paxil? Why does it seem fortuitous that we are at this point?
2. The FDA Focus on New Users: Why does the FDA believe that the barriers to prescription in new users should be stronger than those for current users? There are no studies that indicate that the excess risk dissipates over time. Presumably those on the drug, whether new or long-standing, are exposed to the risk. It is not sufficient to determine if people are doing well on the drug since the adverse effect is a silent risk. It seems that those already on the drug should have to go through the same process as new users — and the recommendation should be to change the regimens as soon as possible if the guidance from the FDA is to be sensible. There is no basis for separating the recommendation for new users from those of current users. And if it should be the last option for new users, then it should be the same for current users.
3. The Feasibility of Applying the Restrictions: Can the provisions specified by the FDA be reliably applied? How will doctors ensure that patients are given the information about the risk and that they understand? Will the FDA supply tools? Who will monitor the prescribing? Given the challenges in guiding physician behavior, I was wondering how the program will be implemented. I am supposing that this approach is in effect now — and if I prescribe Avandia to a new user tomorrow, I am wondering what I need to do and what will happen to me if I do not do whatever I am supposed to do. And who is going to tell me what to do? And what about my colleagues who did not notice the announcement? I assume the FDA knows what they are doing, but it is not so simple to leave it on the market, institute restrictions, and expect them to be followed. The FDA has some experience with restrictions — there are roughly 30 drugs now carrying a Risk Evaluation and Mitigation Strategy. But I am not sure they have imposed such a program on a drug as widely prescribed as Avandia.
4. The Failure of the Surrogates: This episode is yet another example of how surrogate outcomes like blood sugar control can be misleading. Knowing how well a drug controls blood sugar, cholesterol, or blood pressure (or any other risk factor) is not enough to know what effect it has on people. Drugs that are better at controlling a risk factor like blood glucose may paradoxically increase risk — we have seen that before. Ask Bristol Myers, the makers of muraglitazar — great glucose control, but it increased cardiovascular risk.
5. Will We Have Another Avandia? Finally, will we learn anything and change anything from watching the misdeeds of the company? There were dirty tricks and lack of transparency, episodes of intimidation of critics, and denial of responsibility. The Senate Finance Committee exposed individuals and the company, and the reports made for interesting reading. But how can we move forward in a way that such shenanigans can be avoided? In the end, the story is as much about Glaxo and the profession of medicine as it is about Avandia. And I fear that the culture has not changed — reputations seem to have survived intact, and the beat goes on. Profits were made: the sales of Avandia were extended by the misdeeds, and billions of dollars in revenues were preserved for a long time, even as many were likely exposed to risks that could have been avoided with a different regimen. Remember that a strong majority of the FDA advisory committee in 2007 agreed that Avandia increased the risk of heart attacks. What truly needs to be remedied is how we all work together to get the best information to the public. Needed studies must be done in a timely way so we can equip clinicians and their patients with the evidence that allows them to make the best choices.
September 24th, 2010
Xience V Stent Still Strong at 2 Years
Larry Husten, PHD
Two large trials presented at TCT continue to demonstrate the long-term superiority of the everolimus-eluting stent (EES) over the paclitaxel-eluting stent (PES).
Gregg Stone presented two-year outcomes from more than 3500 patients randomized in the SPIRIT IV trial to either the Xience V or the Taxus stents. At two years, the rate of target lesion failure — defined as cardiac death, target vessel MI, or ischemia-driven target lesion revascularization — was 9.9% in the Taxus group compared to 6.9% in the Xience V group (p<0.003). The rate of stent thrombosis was 1.25% in the Taxus group compared to 0.33% in the Xience V group (p=0.002).
In the two-year followup of the COMPARE trial, which included nearly 1800 patients, Peter Smits reported that the rate of death, nonfatal MI, and TVR was 13.7% in the Taxus group compared to 9.0% in the Xience group (p=0.0016). Definite or probable stent thrombosis was 3.9% in the Taxus group compared to 0.9% in the Xience group (p<0.0001).
September 24th, 2010
ACC Will Co-Sponsor TCT Symposium in 2011
Larry Husten, PHD
The American College of Cardiology (ACC) will be a co-sponsor of the TCT Symposium in 2011, the ACC and the Cardiovascular Research Foundation (CRF) announced on Thursday. The arrangement will deepen the existing relationship between the two organizations, which already collaborate on the Innovations in Interventions (i2) Summit at ACC’s Annual Scientific Sessions.
In a blog post, incoming ACC president David Holmes wrote:
“Today’s announcement means the two groups will work together on a partnership that involves sharing content and distribution of educational materials. The ACC and CRF will form a physician-led ‘Collaborative Council’ of senior physician leaders that will meet regularly to review progress towards established objectives and to set the strategic direction of the affiliation. ACC and CRF staff will also meet regularly to share best practices, consider joint procurement of vendors, consider reciprocal exposition space at annual meetings, and explore collaboration around industry training programs.”
September 23rd, 2010
FDA and EMA Split on Fate of Avandia
Larry Husten, PHD
The FDA and the European Medicines Agency announced separate and divergent decisions on the fate of rosiglitazone (Avandia) today.
On the one hand, the FDA announced that it would allow rosiglitazone to remain on the market, though only with severe restrictions on its use. Additionally, the FDA said it would require the drug’s manufacturer “to convene an independent group of scientists” to re-adjudicate the controversial RECORD trial. The FDA also placed the TIDE trial on “full clinical hold”. (Click here for more FDA documents.)
On the other hand, the European Medicines Agency announced it was recommending suspension of rosiglitazone and said the drug will no longer be available in Europe “within the next few months.”
Several hours after the announcements, the New England Journal of Medicine published a perspective on rosiglitazone by the FDA’s Janet Woodcock, Joshua Sharfstein, and Margaret Hamburg.
September 23rd, 2010
Fondaparinux Effective in Superficial-Vein Thrombosis
Larry Husten, PHD
In the randomized, double-blind CALISTO (Comparison of Arixtra in Lower Limb Superficial Vein Thrombosis with Placebo) trial, 3002 patients with acute, symptomatic superficial-vein thrombosis in the legs, but without DVT or symptomatic PE, received either fondaparinux (2.5 mg) or placebo for 45 days. The primary efficacy endpoint ─ a composite of all-cause death, symptomatic PE or DVT, symptomatic extension to the saphenofemoral junction, or symptomatic recurrence of superficial-vein thrombosis ─ was reduced by 85%: from 5.9% in the placebo group to 0.9% in the fondaparinux group (p<0.001). There was no difference between the groups in mortality. All the other components of the composite endpoint were significantly reduced by fondaparinux. In their report in the New England Journal of Medicine, the investigators calculated that 20 patients would need to be treated with fondaparinux to prevent 1 primary endpoint event, and 88 to prevent DVT or PE.
In an accompanying editorial, Lee Goldman and Jeffrey Ginsberg praise the conduct of the trial and note that fondaparinux, along with several other newer drugs, may be preferable to unfractionated heparin and warfarin. But, they warn, it is unclear whether the superior risk-benefit profile of the drug justifies the extra price. They recommend that the FDA mandate post-approval trials “to document the costs, the effects on quality of life, and the cost-effectiveness of new interventions.” Until these data are available, they write, “it would seem premature to recommend that fondaparinux be used routinely in the treatment of superficial-vein thrombosis.”
September 23rd, 2010
Howdy, PARTNER!
Michael Mack, M.D., E Murat Tuzcu, MD, L. David Hillis, MD and Richard A. Lange, MD, MBA
CardioExchange welcomes Mike Mack and E. Murat Tuzcu, investigators for the PARTNER trial, an ongoing, randomized study of transcatheter aortic valve implantation (TAVI) in patients with severe aortic stenosis at high surgical risk. The first reported findings, published in the New England Journal of Medicine, showed an impressive 20% absolute reduction in 12-month mortality with TAVI compared with standard treatment in 358 patients who were ineligible for surgical aortic valve replacement (AVR). Here, the investigators answer a series of questions posed by David Hillis and Rick Lange, moderators of the Interventional Cardiology blog.
Q: Almost 85% of patients in the standard-therapy group underwent balloon aortic valvuloplasty (BAV), which is known to be largely ineffective and potentially harmful. How many of the complications in the standard-therapy group were due to valvuloplasty?
A: Overall survival was slightly better in standard-treatment patients who received a BAV compared with those who did not. There were 2 strokes within 7 days of a BAV.
Q: Of the patients who underwent TAVI, 30% died within a year, and 25% of the survivors continued to have NYHA class III/IV symptoms. Did these individuals differ from those who survived and had an improvement in symptoms? If so, how?
A: 95 TAVI patients (53%) survived with NYHA class I/II symptoms, whereas only 38 (21%) patients in the standard-therapy group survived with NYHA class I/II symptoms. We have not yet analyzed the data to determine the differences between patients whose symptoms improved and those whose symptoms did not.
Q: Despite the fact that all patients in the study were deemed unsuitable for surgery, 12 (7%) of those assigned to standard therapy underwent AVR, with a 1-year death rate of 33%, which is similar to the rate of death with TAVI (31%). Why should TAVI — rather than AVR — be the new standard of care for these patients?
A: 12 patients is too small a group from which to draw any conclusions. We will gain further data regarding this question when the results of Cohort A, which compared TAVI and surgical AVR, are available.
Q: Only 358 (12%) of the 3105 patients screened for the study were randomized. Of patients determined not to be suitable candidates for AVR, were only a minority suitable for TAVI?
A: An additional 700 screened patients were entered into Cohort A of the PARTNER trial. Therefore, approximately 1/3 of screened patients were enrolled, which is in line with other published studies.
Q: What was the operator experience with TAVI before participation in the study?
A: Only 3 of the 21 centers had any previous experience from feasibility trials. For the other 18 centers, this represented their initial TAVI experience after intensive training and proctoring.
Q: Based on the results of a study with 12 months of follow-up, you propose that TAVI should be the new standard of care for patients with aortic stenosis who are not suitable candidates for surgery. Why not wait for longer follow-up before making this claim?
A: Of course, longer-term follow-up is important and ongoing. The median follow-up to date is 1.6 years, and the longest patient follow-up is 2.8 years. Based on an absolute 20% improvement in survival at 12 months and survival curves that continue to diverge, we are confident in this recommendation.