CLINICAL IMAGES / Bioresorbable Stent Restenosis: New Devices, Novel Situations

Abstract: A 58-year-old man presented to our hospital with effort angina. Ten months prior, he was treated with a Bioresorbable vascular scaffold (BVS). During the current admission, an image angiographically compatible with in-BVS restenosis at the circumflex ostium with a radiolucent image in the ostial left anterior descending artery was shown. BVS failure is very infrequent and this is one of the first cases of BVS restenosis described. Thus, data on the best management option are scarce. We treated it like a drug-eluting stent restenosis, performing first an intracoronary optical coherence tomography scan in order to identify the left descending radiolucent image and to prepare the best treatment strategy.

J INVASIVE CARDIOL 2014;26(12):E164-E166

Key words: bioresorbable vascular scaffold, BVS, in-BVS restenosis, complications

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A 58-year-old man presented to our emergency room complaining of recent-onset increasing effort angina. Coronary artery disease risk factors included dyslipidemia and family history. Due to angina, the patient underwent cardiac catheterization 10 months prior to the current admission, which displayed a single and severe stenosis in the proximal circumflex artery (Cx). He was treated successfully with a second-generation Absorb 3.5 x 12 mm bioresorbable vascular scaffold (BVS; Abbott Vascular) (Figures 1A and 1B). Repeat catheterization during the current admission revealed an image angiographically compatible with in-stent restenosis (ISR) at the circumflex ostium, with a radiolucent image in the ostial left anterior descending (LAD) artery (Figure 1C) without other new stenosis. 

There are a few bioresorbable stents commercially available, and since they are intended to completely disappear, they are supposed to present some potential benefits in cases where vessel scaffolding is only needed transiently, such as restoration of vasomotor functions; positive vessel remodeling; elimination of sources of chronic vessel irritation; no permanent implant to complicate future interventions; no artefacts in future invasive imaging computed tomography scans; potential reduction in the need for prolonged antiplatelet therapy; etc. The Absorb BVS, which is one of the more widely used scaffolding devices,¹ has an everolimus coating and a completely resorbable polylactide scaffold. It has shown excellent results in both animals² and humans (up to 5 years),¹ similar to other last-generation drug-eluting stents. These favorable publications have justified extending BVS indications to small vessels, acute ST-elevation myocardial infarction cases,³ and chronic total occlusions.⁴ While it’s important to consider the BVS’s features and limitations, such as thicker struts, limited suitability in bifurcation lesions, and slower inflation requirement during deployment, it seems logical to expand their use in appropriate situations. 

However, if we use new devices we need to be prepared for new situations. In the present case, we initially diagnosed an ISR, although many circumstances may have contributed to this “stent failure,” such as technical issues during implantation, gradual disappearance of supportive scaffold-radial strength, elastic recoil, patient neointima or thrombosis. The global literature on BVS use is limited, and BVS thrombosis is very infrequent;¹ to the very best of our knowledge, this case is one of the first descriptions of BVS restenosis (or failure). Thus, data on the best management option (a paclitaxel-coated balloon, a drug-eluting stent, or another BVS) are scarce for BVS restenosis. Several questions arose, since we were treating a stent that was going to disappear in the next 12-36 months. Do we need a new strong stent inside? Is this new stent going to be malapposed when the BVS struts disappear? What is the correct drug choice and duration for antiplatelet therapy?

We finally decided to treat this case like a drug-eluting stent IRS, but first performed intracoronary OCT in order to identify the left descending radiolucent image and to prepare the best treatment strategy. The OCT (Dragon Fly, St Jude Medical/QAngio OCT 1.0, Medis) and the three-dimensionally rendered imaging nicely characterized that strange radiolucent image as BVS struts prolapsed to the left anterior descending artery with neointimal hyperplasia, warranting a bifurcation treatment (Figures 1D and 1E). Under OCT guidance, we wired inside the BVS and predilated the Cx artery (and the BVS). The possibility of in-stent thrombosis was discarded, since a thick neointimal coverage and no thrombus were present inside the BVS (Figure 1F). Then, we implanted a 3.5 x 16 mm drug-eluting stent at the level of the Cx and a 3.5 x 12 mm drug-eluting stent at the left anterior descending-left main level using a culotte technique (Figures 2A-2D). The final result was good, as confirmed by angiography and OCT. A video demonstration of this case is available here. The use of intracoronary OCT imaging and advanced imaging tools provided us with a unique opportunity to understand and manage complex and infrequent conditions like this one.

BVS failure is a novel complication that we will probably see more often as the number of BVS-treated patients increases; therefore, we still have important questions to answer in the next years.

References

1. Onuma Y, Dudek D, Thuesen L, et al. Five-year clinical and functional multislice computed tomography angiographic results after coronary implantation of the fully resorbable polymeric everolimus-eluting scaffold in patients with de novo coronary artery disease: the ABSORB cohort A trial. JACC Cardiovasc Interv. 2013;6(10):999-1009.
2. Onuma Y, Serruys PW, Perkins LE, et al. Intracoronary optical coherence tomography and histology at 1 month and 2, 3, and 4 years after implantation of everolimus-eluting bioresorbable vascular scaffolds in a porcine coronary artery model: an attempt to decipher the human optical coherence tomography images in the ABSORB trial. Circulation. 2010;122(22):2288-2300.
3. Kocka V, Maly M, Tousek P, et al. Bioresorbable vascular scaffolds in acute ST-segment elevation myocardial infarction: a prospective multicenter study ‘Prague 19’. Eur Heart J. 2014;35(12):787-794. Epub 2014 Jan 12.
4. Gori T, Guagliumi G, Münzel T. Absorb bioresorbable scaffold implantation for the treatment of an ostial chronic total occlusion. Int J Cardiol. 2014;172(2):e377-e378. Epub 2014 Jan 11.

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From the Cardiology Department, Cardiovascular Institute, Hospital Clínico San Carlos, Madrid, Spain.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors report no conflicts of interest regarding the content herein.

Manuscript submitted April 16, 2014, provisional acceptance given May 9, 2014, final version accepted May 13, 2014.

Address for correspondence: Dr Iván Javier Núñez-Gil, C/Prof Martin Lagos SN, 28040 Madrid, Spain. Email: ibnsky@yahoo.es