ACC-i2 2015: Strategies to Enhance PCI Results, TAVR Highlighted
SAN DIEGO, CA—Late-breaking clinical research presented March 14-16, 2015, at the American College of Cardiology/i2 Scientific Session spanned multiple subspecialties. Among the most headline-grabbing topics were device and pharmacologic strategies to improve PCI outcomes, long-term TAVR results, and the use of coronary CT angiography (CTA) for evaluating patients with suspected CAD.
Optimizing PCI Outcomes
One of the biggest studies—both literally and figuratively—presented at the meeting was the 10,732-patient TOTAL trial, which evaluated the addition of routine manual thrombectomy to primary PCI. Thrombectomy failed to improve clinical outcomes through the first 180 days.
In an interview with TCTMD, David E. Kandzari, MD, of Piedmont Heart Institute (Atlanta, GA), noted that the trial follows one study (TAPAS) that suggested thrombectomy reduces mortality and another larger study (TASTE) that showed no benefit. “So this is kind of the deal breaker in many ways,” he said.
He pointed out that although stroke rates overall were low, they were higher in the thrombectomy group. “I think there's a lot more interest now in this trial in learning what the contributing factors were to stroke,” said Dr. Kandzari, who was the 2015 chair of TCT@ACC-i2.
Overall, the trial is “probably going to further reduce the use of thrombectomy and make people a little more conservative about its use,” Dr. Kandzari said. “But whether it’s still required for bailout purposes…, whether there's a more selective application for it, I think still remains outstanding.”
Another trial, MATRIX, included comparisons of radial and femoral access and of bivalirudin and heparin for invasively treated ACS patients. The radial approach reduced net adverse clinical events—driven by reductions in death and major bleeding—compared with femoral access. Bivalirudin failed to improve composite outcomes compared with heparin but was associated with reduced rates of death and major bleeding.
Touching on an area that has come into greater focus in recent years—complete revascularization—the DANAMI3-PRIMULTI trial randomized 2,239 STEMI patients to conventional primary PCI, ischemic postconditioning, or deferred stenting. The 627 patients who had successful PCI of the infarct-related artery and multivessel disease were then randomized to no additional PCI or FFR-guided complete revascularization before discharge.
Complete revascularization reduced the 1-year rate of all-cause death, MI, or ischemia-driven revascularization of noninfarct-related arteries (primary endpoint); the difference arose from protection against repeat procedures.
Long-term Secondary Prevention After MI
The PEGASUS-TIMI 54 trial included 21,162 aspirin-treated patients who were stable at 1 to 3 years after MI and were randomized to either a higher or lower dose of ticagrelor (Brilinta; AstraZeneca) or placebo. Through 3 years of follow-up, both doses reduced the rate of cardiovascular death, MI, or stroke. Ticagrelor also increased major bleeding but not intracranial hemorrhage or fatal bleeding.
Pointing to the relatively small absolute benefit seen with ticagrelor, the increase of a similar magnitude in bleeding risk, and elevated rate of dyspnea in the active treatment arms, a panelist at the presentation said the study “adds to the evolving trend of using two platelet inhibitors in long-term coronary artery disease, but I think we should be a little bit cautious….”
TAVR Holds Up Over the Years
Two presentations highlighted the performance of the first-generation Sapien (Edwards Lifesciences) and CoreValve (Medtronic) devices in patients with severe symptomatic aortic stenosis and at high surgical risk.
Five-year follow-up of Cohort A of the PARTNER trial showed that the risk of death was higher but remained similar between Sapien and surgical valve replacement (67.8% vs 62.4%).
“We're still humbled by… high mortality rates even at 5 years, and it really reflects the comorbidities of these patients [and is] not related to their aortic valve disease,” Dr. Kandzari said.
A separate presentation involved the 2-year follow-up of the CoreValve US Pivotal Trial and showed that the survival advantage for TAVR over surgical valve replacement seen at 1 year was maintained—and possibly grew—through another year. In addition, the risk of any stroke was lower in the TAVR arm.
Dr. Kandzari noted that both trials used first-generation devices and that there have already been some improvements made. “We can only expect the procedure to get safer and more effective, [and] the technologies to be more durable and effective as well,” he said.
Durability has been one of the major questions surrounding TAVR, which is why the first trials were in high-risk patients, he said. Now, the procedures are starting to be performed in lower-risk groups.
“I think those results at 5 years and at 2 years… just continue to provide endorsement for advancing this procedure to a broader population,” Dr. Kandzari said.
Another TAVR study at the meeting examined early clinical outcomes following use of the new-generation Sapien 3 valve (Edwards Lifesciences), which has a skirt designed to reduce paravalvular leak. According to data from 2 nonrandomized registries embedded within the PARTNER II trial, 30-day event rates were lower than those seen in prior trials of balloon-expandable valves.
Also on the TAVR front, the DEFLECT III trial demonstrated that a novel neuroprotection device—called TriGuard (Keystone Heart; Caesarea, Israel)—is safe and has the potential to protect against cerebral lesions stemming from the procedure. Clinical outcomes, however, were not improved with the device.
Using CTA to Evaluate Suspected CAD
In the PROMISE trial, researchers randomized 10,003 symptomatic patients without diagnosed CAD to an initial strategy of coronary CTA or functional testing. There was no difference between groups in the rate of death, MI, hospitalization for unstable angina, or major procedural complication (primary outcome) through 25 months of follow-up. Coronary CTA was associated with greater use of cardiac catheterization within 90 days and a lower rate of catheterization showing no obstructive CAD compared with functional testing.
The presenter said the findings will likely strengthen the level of evidence supporting both coronary CTA and functional testing in the guidelines and called coronary CTA “a viable alternative to functional testing.”
Dr. Kandzari agreed and suggested that the findings might have an impact on reimbursement.
“[W]e've had a lot of differential reimbursement with the use of CT angiography as a routine strategy to evaluate for coronary artery disease in the United States,” he said. “So a study that showed similar outcomes and similar identification of disease with one imaging method versus more traditional methods of stress testing and assessment [is welcome]. My hope is that this study also will help lead toward greater adoption and reimbursement for CT angiography.”
As to whether this could potentially lead to guideline changes, Dr. Kandzari said: “My expectation would be that we’ll see more incorporation of CT angiography as an alternative to more traditional assessment for ischemic heart disease.”
Coronary CTA was evaluated in a second trial as well. SCOT-HEART randomized 4,146 patients who were referred to dedicated chest pain clinics in Scotland to standard care with or without coronary CTA. The addition of CTA clarified diagnoses, reduced unnecessary tests, and resulted in a nonsignificant reduction in nonfatal MI and death due to coronary heart disease.
DES vs Surgery Over the Long Term
Two trials examined long-term outcomes of PCI with DES compared with CABG in patients with advanced coronary disease.
In the 4-year follow-up of BEST, which included patients with multivessel disease, the rate of death, MI, or TVR was higher among those who received everolimus-eluting stents vs those who underwent surgery. The difference was driven by a higher rate of TVR.
And in the 5-year follow-up of PRECOMBAT, which included patients with unprotected left main disease, safety and efficacy were comparable between those who received the sirolimus-eluting Cypher stent (Cordis) and those who underwent CABG. There was no difference in MACCE, although ischemia-driven TVR was more frequent in the DES group.
Additional studies presented at the meeting included:
REGULATE-PCI: A novel anticoagulation system that includes a rapid reversal agent increased moderate-to-severe bleeding and serious allergic reactions without providing improvement in clinical outcomes for PCI patients.
EMBRACE STEMI: In first-time STEMI patients undergoing PCI after a proximal or mid-LAD occlusion, the administration of a novel mitochondrial targeting peptide—Bendavia (Stealth BioTherapeutics; Newton, MA)—failed to reduce infarct size.
After Eighty: Patients over age 80 with NSTE-ACS or unstable angina were less likely to die, suffer an MI, or need urgent revascularization with an early invasive strategy compared with conservative management.
ERRICA: Remote ischemic conditioning prior to on-pump CABG in high-risk patients failed to reduce long-term adverse events.
TVT Registry: Initial US use of transcatheter mitral valve repair with MitraClip has resulted in high procedural success and low complication rates.
In a small before-and-after study, catheter-based denervation of the pulmonary artery was associated with improvements in functional and hemodynamic outcomes and a reduction in pulmonary arterial hypertension–related events in patients with pulmonary hypertension of various causes.
A focused session on building a career in cardiology provided fellows with the key messages of networking with purpose, learning to say yes (and also no), and thinking creatively.
Presentations at: American College of Cardiology/i2 Scientific Session; March 14-16, 2015; San Diego, CA.
- Dr. Kandzari reports receiving consulting fees/honoraria from Boston Scientific, Medtronic, Micell Technologies, and Thoratec.