While partially bioresorbable stents have been available in Europe for a number of years, the first fully resorbable stent, Abbott’s ($ABT) Absorb, has only recently gained approval in the U.S. and Europe. And though there are many benefits to a stent that completely reabsorbs within two to three years, the technology’s novelty gives rise to several challenges, said a group of U.S. and European cardiologists at a roundtable discussion Thursday.
A resorbable stent is attractive for use in younger patients, who will have to live with coronary artery disease for many more years, noted Dr. Jeffrey Moses, director of the Center for Interventional Vascular Therapy at New York-Presbyterian Hospital/Columbia University Medical Center, and Dr. Michael Rinaldi, Medical Director of Clinical Research at Sanger Heart & Vascular Institute, on the call.
Stenting that does not leave a metal scaffold allows more freedom for follow-up procedures down the line. Bioresorbable stents would also perform well in patients with long arterial lesions, where a surgeon would otherwise “pave the entire vessel with stents,” raising the risk of late stent thrombosis, Rinaldi said.
However, the panelists highlighted the steep learning curve that accompanies the Absorb, and noted surgeons’ familiarity with partially resorbable stents, and the preparation and post-procedure steps for these stents, as an advantage for the older technology.
The steep learning curve comes primarily from the thicker struts of the Absorb. Not only do they protrude more into the lumen than do partially resorbable models, but they also cover a greater proportion of the vessel wall when they are implanted, said Dr. Robert Byrne, a cardiologist at Deutsches Herzzentrum in Munich.
These differences require a different implantation technique, including more aggressive vessel preparation and post-procedure dilation, Byrne said. Surgeons are also encouraged to use intravascular ultrasound to help size the vessel and place the implant. All of these factors can add steps, time and cost to stenting procedures, potentially making a bioresorbable stent a less attractive option for healthcare providers.
With regards to cost, there is, as expected, a cost premium to a first-generation device such as said procedure for third-party payers and patients as well as for hospitals should also be considered, said Dr. Elizabeth Holper, chief clinical quality officer and medical director of Interventional Cardiology Research at The Heart Hospital Bayor Plano. But in the long term, cost will not likely remain a concern, Byrne said. If the U.S. follows Germany’s example, insurers will deem the technology a treatment worth funding and reimburse hospitals for it.
All in all, the panelists agreed that there is still insufficient data for physicians to make truly data-driven decisions involving bioresorbable stents. But “a plethora of data” should become available within the next year or two, and we should be on “much firmer ground” regarding the advantages and limitations of fully resorbable stents, Moses said.
With the recent FDA approvals of Abbott's Absorb and Boston Scientific's ($BSX) partially resorbable Synergy stent, the roundtable was presented by Boston Scientific to discuss what patients and physicians can expect from these new technologies. Boston Sci's Synergy is the first FDA-approved partially resorbable stent.
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