J INVASIVE CARDIOL 2017;29(7):E79-E80.
Key words: bioresorbable scaffold, aneurysm
A 67-year-old man was referred for coronary angiogram due to rest angina. Coronary angiogram demonstrated severe stenosis in the mid-segment of the left anterior descending (LAD) coronary artery (Figure 1A). Under intravascular ultrasound guidance, the target lesion was successfully treated (Figure 1B) with the implantation of a 3.0 x 18 mm Absorb bioresorbable stent (BRS; Abbott Vascular). Three months later, an angiogram was performed due to recurrence of angina and a positive treadmill test. Surprisingly, there was an aneurysm at the site of previous BRS deployment (Figure 1C). Intravascular ultrasound evaluation highlighted the aneurysm (Figures 1D, 1E, 1F).
Bioresorbable vascular scaffolds have emerged as an important alternative to metallic stents for the treatment of obstructive coronary artery disease. These devices can potentially decrease inflammation due to reabsorption of the polymer and struts within the first 24-36 months after stent deployment. Due to their conformation, however, these devices have been shown to induce greater neointimal response early within the first months after implantation.1
Inflammation plays a central role in coronary aneurysm formation, but this complication may also be attributed to residual dissection, deep arterial wall injury, and hypersensitivity reactions to the drug, polymer, or metal.2 Gori et al analyzed 102 lesions treated with BVS and found that 55 out of 102 lesions (54%) had at least one evagination at 12 months. The presence of evaginations was strongly associated with malapposition (P<.01) and strut fractures (P=.01).3
The clinical course of coronary artery aneurysms after drug-eluting stent implantation is variable. Some aneurysms naturally resolve, but some can lead to complications such as stent thrombosis.4 In order to avoid such complications, it is important to reduce as much as possible the chance of exposing causal factors, and intravascular imaging may be needed in order to accurately assess the results of stent deployment and apposition.
1. Otsuka F, Pacheco E, Perkins LE, et al. Long-term safety of an everolimus-eluting bioresorbable vascular scaffold and the cobalt-chromium Xience V stent in a porcine coronary artery model, Circ Cardiovasc Interv. 2014;7:330-342.
2. Luscher TF, Steffel J, Eberli FR, et al. Drug-eluting stent and coronary thrombosis: biological mechanisms and clinical implications, Circulation. 2007;115:1051-1058.
3. Gori T, Jansen T, Weissner M, et al. Coronary evaginations and peri-scaffold aneurysms following implantation of bioresorbable scaffolds: incidence, outcome, and optical coherence tomography analysis of possible mechanisms. Eur Heart J. 2016;37:2040-2049. (Epub 2015 Nov 4).
4. Alfonso F, Pérez-Vizcayno MJ, Ruiz M, et al. Coronary aneurysms after drug-eluting stent implantation: clinical, angiographic, and intravascular ultrasound findings. J Am Coll Cardiol. 2009;53:2053-2060.
From the Cardiology Division, Hospital de Clínicas de Porto Alegre, Brazil and the Universidade Federal do Rio Grande do Sul, Brazil.
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 accepted April 24, 2017.
Address for correspondence: Gustavo Neves de Araújo, Hospital de Clínicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Brazil. Email: firstname.lastname@example.org