ESC Congress 2012: Diverse Lineup of Practice-Changing Presentations

MUNICH, Germany—Last week’s European Society of Cardiology (ESC) Congress, held August 26 to 29, provided fresh results for a wide range of technologies and approaches as well as numerous guideline recommendations for clinical practice.

In an interview with TCTMD, Spencer B. King III, MD, of Saint Joseph's Heart and Vascular Institute (Atlanta, GA), noted that the meeting offered much relevant news to interventionalists.

Choices in Medical Therapy

However, the most surprising finding of all came not from an interventional trial but from TRILOGY ACS, Dr. King commented. The study pitted long-term prasugrel against clopidogrel in patients with unstable angina and STEMI who did not undergo revascularization, finding that the newer drug did not reduce ischemic events.

“Everyone thought prasugrel would win, and it didn’t,” he said. The lesson, Dr. King advised, is that “[p]rasugrel seems to be most helpful when you need an antiplatelet the most: acutely at the time of angioplasty. It has a rapid onset and is more reliable. . . . [If] you need a lot of antiplatelet action, then these more potent agents are worth it. And if [you don’t], maybe they’re not.”

Dr. King predicted that WOEST, which assessed anticoagulation in conjunction with PCI, may be the most influential trial of the week. “When we say stopping double antiplatelet therapy, people usually interpret that to mean stopping clopidogrel and continuing aspirin,” he said, “because in people with coronary disease, the recommendation is aspirin for life.”

Instead, WOEST tested what would happen when aspirin was eliminated in patients undergoing PCI while also taking an antiplatelet and an oral anticoagulant. Compared with patients on triple therapy, those on only an anticoagulant and clopidogrel experienced fewer ischemic events and less bleeding at 1 year.

Other results came from a prespecified subanalysis of 17,779 post-MI patients from the TRA2P-TIMI 50 trial, which compared the investigational drug vorapaxar vs. placebo in a cohort of more than 26,000 patients with history of atherothrombosis. The subanalysis showed that for patients who are stable after MI, extended use of the thrombin receptor antagonist vorapaxar on top of standard antiplatelet therapy reduces the risk of cardiovascular death and other thrombotic events at 3 years. However, the benefit was accompanied by an increase in bleeding events.

An update to HPS-THRIVE, the largest randomized trial to date on extended-release niacin plus laropiprant (a drug to reduce facial flushing) vs. placebo in high-risk patients, found no unexpected adverse effects from treatment through 3-year follow-up. Most patients who tolerated the drug combination at 8 weeks remained compliant over the long term.

Several trials directly addressed medical therapy in the context of PCI.

A new analysis from the ATLAS ACS 2-TIMI 51 trial, which enrolled over 15,000 ACS patients, found that those with STEMI stand to benefit from a twice-daily 2.5-mg dose of the novel anticoagulant rivaroxaban. At 24 months, rivaroxaban (either 2.5 mg or 5 mg) held an overall advantage compared with placebo for the primary efficacy endpoint, a composite of CV death, MI, and stroke. While the 5-mg dose failed to reduce cardiovascular death, the 2.5-mg dose proved successful at reducing not only cardiovascular death but all-cause death and came with less bleeding.

The MADONNA study found that, among patients who show poor clopidogrel response after PCI, an individually tailored regimen involving repeat loading doses of clopidogrel and/or prasugrel can improve outcomes at 1 month compared with standard treatment. The findings lend support to the idea of personalized antiplatelet therapy. Initially, 106 patients out of 403 (26%) were classified as nonresponders after the first clopidogrel dose but after up to 5 rounds of reloading guided by platelet function testing, only 2 patients (0.5%) failed to respond.

Imaging, Lesion Assessment Hone in on Disease

Dr. King also highlighted the DeFACTO trial. The study comparing conventional CT angiography with a noninvasive method of measuring fractional flow reserve (FFR) based on data from CT angiography was “interesting,” he said, “but raised more questions than it answered.”

Admittedly, the trial did not meet its primary endpoint when finding FFR-CT’s diagnostic accuracy to be 73%, Dr. King noted. But that “doesn’t negate it at all,” he stressed. “It says that this is a technology fairly early in development that has the potential to have enormous clinical impact on the way things are done. It’s just not there yet.”

The concept of FFR-CT matters because, “[i]n theory, with high enough throughput, you could have a cheap test that would tell you a lot and if appropriate action were taken you could perhaps prevent events and also prevent inappropriate intervention and affect health care costs,” Dr. King explained. “That’s a huge leap but since all those things are in play with this technology, people will hopefully continue to be interested in this.”

FAME 2 demonstrated the potential for functional testing by finding that, in patients with stable CAD and at least 1 proven ischemic stenosis, PCI guided by FFR plus optimal medical therapy markedly reduces the need for urgent revascularization compared with medical therapy alone.

According to Dr. King, the message is clear for interventional cardiologists. “From the interventional approach, you’d say, ‘Wow, this is good. This overturns COURAGE, at least for patients who have known, clear cut obstructive disease. We should go ahead and stent them,’” he related. But, Dr. King added, skeptics will say the lack of blinding could have biased the study and the higher use of antiplatelets in the PCI arm could have tilted the advantage toward intervention.

The CORE320 trial, meanwhile, found that a noninvasive strategy integrating CT angiography with CT myocardial perfusion imaging shows strong diagnostic accuracy in identifying patients who have flow-limiting CAD and need revascularization.

Trials Attempt to Optimize Angioplasty

Several studies continued to examine the best approach to PCI. Not all results were positive.

Although the IABP-SHOCK II study found no harm from using intra-aortic balloon pumps in patients with AMI complicated by cardiogenic shock, the technique did not lower short-term mortality compared with optimal medical therapy when early revascularization was planned. The question now, said Dr. King, is what other ventricular assist devices could be used in this setting. “If the balloon pump didn’t help very much, maybe something else would,” he suggested.

Furthermore, the randomized CARDia trial looking at diabetic patients with multivessel disease and either stable angina or NSTE ACS found no clear evidence to support routine use of PCI over CABG.

The PROTECT trial supplied an unexpected conclusion: In the largest head-to-head comparison of DES to date, no difference existed between stent thrombosis rates at 3 years for a first-generation sirolimus-eluting stent and a second-generation zotarolimus-eluting stent. The similarity is good news for the millions of patients who have received the earlier device, the study investigator said.

All the effort to improve STEMI care seems to be bearing fruit, according to data from the FAST-MI program. Over the past 15 years, the population of patients hospitalized for STEMI has changed such that more recently treated patients tend to be younger and lack comorbidities or previous heart disease. Increased reperfusion use and better medical management have contributed toward drastic reductions in mortality.

Yet a survey sponsored by the European Association of Percutaneous Cardiovascular Interventions (a branch of the ESC) found a less positive picture. While sizeable improvements have been made in expanding the availability of primary PCI across Europe, alarming geographic variability remains. The research was conducted from 2010 to 2011 and included 33 European countries.

Valves Take to the Real World

Several ESC presentations reported clinical outcomes from registries of transcatheter aortic valve replacement (TAVR) in a variety of locales including Europe as a whole, France, and Germany. Real-world data on mitral valve repair also were released. Overall, results were good and in keeping with what had been shown by randomized trials. German registry data also indicated that TAVR improves quality of life and reduces hospitalization.

In addition, an observational study of TAVR found that the presence of subannular aortic calcification and a pattern of diffuse calcium distribution in the coronary cusps both predict substantial levels of postprocedural valvular regurgitation. Another presentation explored premarket clinical results for a dedicated TAVR device for transapical access.

Other Lessons for Practice

ESC Congress 2012 provided updated guidance for clinical practice in a number of areas relevant to interventional cardiology that span STEMI, valvular disease, heart failure, and A-fib. A newly revised universal definition of MI also made its debut.

Additional research included:

 


Source:
Presentations at: European Society of Cardiology Congress; August 26-29, 2012; Munich, Germany.

 

 

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Disclosures
  • Dr. King reports serving on Data and Safety Monitoring Boards for Merck and Wyeth Pharmaceuticals.

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