The annual Transcatheter Cardiovascular Therapeutics conference featured scientific presentations that highlighted clinical approaches no better and no worse than the alternatives, although in the ILLUMENATE Pivotal Trial a novel paclitaxel-coated balloon was found to be superior to routine percutaneous transluminal angioplasty (PTA) in patients with peripheral arterial disease.
Scientific presentations and educational sessions at this year’s Transcatheter Cardiovascular Therapeutics conference were attended by several HealthTrust members as well as Cardiovascular Service Line physician advisor Felix Lee, M.D. The event was held Oct. 29 – Nov. 2 in Washington, D.C., and, judging from booths in the exhibit hall, the development pipeline for interventional cardiovascular devices is teeming with products—many of them not yet ready for prime time in the U.S.
Multiple medical devices impacted by HealthTrust’s contracting strategies in 2016 were among the topics of breaking results from major clinical studies. Beyond the ABSORB II study that has prompted widespread concerns about the first-generation bioresorbable stent (which Dr. Lee will be reporting out on separately), here are some of the presentations that caught our attention:
- Illumien III: This prospective, randomized trial compared optical coherence tomography (OCT)-guided, intravascular ultrasound (IVUS)-guided and angio-guided stent implantation in 450 patients with coronary artery disease. At 30-day follow-up, OCT guidance was found to be non-inferior to IVUS guidance as well as not superior to IVUS plus angiography. Results were simultaneously published in The Lancet.
- BIO-RESORT (TWENTE III): In this prospective, randomized, three-arm trial, two biodegradable polymer-based drug-eluting stents (DES)—Boston Scientific’s Synergy and Biotronik (Orsiro, not available in the U.S.)—and Medtronic’s Resolute, a permanent polymer-based, sirolimus-eluting stent, were compared in an “all-comers” population of patients with coronary artery disease. Non-inferiority goals were met at one year, when target vessel failure in all three arms was at 5 percent. Results were simultaneously published in The Lancet.
- BIONICS: Another prospective, randomized trial compared a ridaforolimus-eluting coronary stent (BioNIR, manufactured by Israel-based Medinol) to a zotarolimus-eluting stent (Medtronic’s Resolute) in a broad, less selected “more comers” population of patients with coronary artery disease. The BioNIR DES, which is not available in the U.S., is comprised of cobalt chromium and 95 percent of the drug is eluted over 180 days. In both arms, the primary endpoint of target lesion failure at one year was 5.3 percent, and there were low rates of stent thrombosis and target lesion revascularization.
- EXCEL: Abbott Vascular’s everolimus-eluting stent (Xience) was compared to bypass graft surgery in this prospective randomized trial involving 1,900 patients with unprotected left main coronary artery disease. Death, stroke and myocardial infarction rates at three years were similar. The study was simultaneously published in the New England Journal of Medicine.
- NOBLE: A prospective randomized trial compared biolimus-eluting stents and bypass graft surgery in patients with left main coronary artery disease. Percutaneous coronary intervention (PCI) with the Biomatrix stent, unavailable in the U.S., had higher major adverse cardiac and cerebrovascular event rates at five years relative to coronary artery bypass graft surgery (performed outside U.S.).
- LEADERS FREE: The first randomized clinical trial dedicated to patients at high bleeding risk who were treated with one month of dual antiplatelet therapy (DAPT) found that two-year clinical and subgroup outcomes with polymer-free, drug-coated stent were significantly better than a comparator bare-metal stent in terms of both safety and effectiveness. Patients with a high bleeding risk comprise approximately 20 percent of patients treated by PCI, yet they are usually excluded from trials of devices and antithrombotic drug regimens. Current recommendations for these patients are one month of DAPT after bare-metal stent implantation and a “shortened” (minimum of three to six months typically) DAPT regimen after DES implantation. LEADERS FREE examined the use of one month of DAPT for both types of stents, specifically studying the BioFreedom drug-coated stent (Biosensors International), which releases Biolimus A9 into the vessel wall over a period of four weeks without the use of a polymer to aid drug delivery.
- SENTINEL trial: The goal of this trial was to compare the safety and efficacy of the Sentinel transcatheter cerebral embolic protection device in reducing cerebral embolization among patients undergoing transcatheter aortic valve replacement (TAVR). Results indicate that routine use of the Sentinel device does not result in a significant reduction in new lesion volume on MRI and non-disabling strokes within 30 days. It adds to the total procedure and fluoroscopic times with a slight increase in vascular complication rates (deployed via the right radial or brachial arteries). Atherothrombotic debris is common following TAVR and was noted in 99 percent of patients in the trial. This included acute thrombus with tissue elements, artery wall, calcification, valve tissue and foreign materials. Efficacy appeared to be lowest in patients receiving the Sapien S3 valve. This is hypothesis-generating and could be due to lower rates of embolization with this device due to smaller sheath sizes and lack of routine predilation. Long-term neurocognitive effects of the noted MRI differences would be informative, particularly as this technology transitions to lower-risk populations. It is unclear if certain patient subsets, such as those with prior strokes/transient ischemic attacks or unrevascularized cerebrovascular disease, would benefit from the use of these devices.
- ILLUMENATE Pivotal Trial: This multi-center, prospective, randomized trial by Sean Lyden, M.D., et al. showed a novel paclitaxel-coated balloon (The Spectranetics Corporation’s Stellarex) to be superior to routine PTA in 300 patients with femoropopliteal peripheral arterial disease from both a safety and efficacy standpoint. At baseline, 43.9 percent of patients had severe calcification and 49.5 percent had diabetes. Follow-up occurred 12 months after the procedure. Among patients who received the drug-coated balloon, 93.6 percent were free from clinically driven target lesion revascularization at follow-up and 82.3 percent had primary patency. The authors noted that the results reaffirm prior data from previous randomized trials.
- IMPRESS trial: Dutch investigators randomized 48 patients with cardiogenic shock to the Impella CP or the intra-aortic balloon pump (IABP). At 30 days, there was no significant difference in mortality (46 percent for Impella, 50 percent for IABP). At six months, the mortality rate was 50 percent in both groups. A meta-analysis combining IMPRESS results with data from two prior randomized controlled trials comparing Impella to IABP. A total of 95 patients were randomized and no differences in mortality or other important endpoints between the groups were found at 30 days or six months. The authors noted that although the Impella has repeatedly shown to provide more hemodynamic support than the IABP, this did not translate into improved clinical outcomes for these very sick patients at a high mortality risk.