Optical Coherence Tomography-Guided Stenting of a Large Coronary Aneurysm: Images at Implantation and at 6 Months

ABSTRACT: Intravascular imaging with optical coherence tomography (OCT) can produce high-resolution images (10–20 µm) of the coronary vessel wall and is being increasingly used to provide insight into coronary pathology and neointima formation following coronary stenting. Fourier domain OCT (FD-OCT) permits a greater scan diameter than time domain OCT and enables larger-caliber coronary structures to be effectively imaged. We present a case of a large, symptomatic and expanding right coronary artery aneurysm treated with FD-OCT-guided pericardial covered stenting and describe the OCT findings immediately after stent deployment and at 6 months. J INVASIVE CARDIOL 2011;23:168–169 ————————————————————

Coronary aneurysms are an unusual variant of atheromatous coronary disease. Indications for intervention are symptomatic coronary insufficiency due to altered flow dynamics, rupture (which is rare) and expanding aneurysms at risk of rupture.¹ Percutaneous exclusion of aneurysms can be undertaken with either PTFE (polyetrafluoroethylene) covered stents, in which the PTFE cover is sandwiched between two stents,² or pericardial covered stents (Over-and-Under^®, TG Medical [USA], Inc., Azusa, California), where the cover is attached to the surface of a single stent leading to potentially greater flexibility and deliverability.^3,4 Fourier domain optical coherence tomography (FD-OCT, C7-XR LightLab Imaging, Inc./St. Jude Medical, St. Paul, Minnesota) provides greater scan diameter than time domain systems, enabling effective imaging of larger coronary vessels. This report demonstrates the use of FD-OCT to guide percutaneous intervention for a large coronary aneurysm and describes for the first time the appearances of pericardial covered stents both immediately after deployment and at 6 months.

Case description. A 60-year-old man presented with worsening symptomatic angina associated with an expanding aneurysm of the right coronary artery demonstrated on serial CT coronary angiography. This was associated with sluggish distal flow on coronary angiography (Figures 1A and B). There was no significant left-sided coronary disease. A decision was taken with the patient to seal the aneurysm percutaneously.

The smaller distal aneurysm was treated first with overlapping 4.0 x 18 mm and 4.0 x 13 mm Over-and-Under pericardial covered stents (Figure 1D). As the dimensions of the proximal aneurysmal segment exceeded the maximum available covered stent length, a novel approach was devised to use a long 4.5 x 32 mm bare-metal stent deployed across the aneurysm to provide a scaffold for subsequent overlapping 4.0 x 23 mm and 4.0 x 18 mm pericardial covered stents. This successfully excluded the aneurysm cavity (Figures 1E and F). OCT imaging using FD-OCT demonstrated the aneurysm cavity (Figure 1C) and appearances of pericardial covered stents immediately after deployment (Figure 2A and D). Repeat angiography at 6 months demonstrated an excellent long-term angiographic result with a small persistent leak demonstrated by FD-OCT to be secondary to separation of the most distal covered stents. This was successfully treated with another 4.0 x 23 mm pericardial covered stent. In those areas where a covered stent alone was deployed, FD-OCT demonstrated a smooth neointima with lucent areas in the vicinity of the pericardial stent cover (Figures 2B and E). In the area where a bare-metal stent was used as a scaffold for subsequent covered stenting, two clear layers of stent struts could be seen with a smooth neointima on the luminal side (Figures 2C and F). The patient remains well and free of angina at 12 months. OCT provides novel insights into the processes of reendothelialization and neointimal formation following coronary intervention, in this case with pericardial covered stents. FD-OCT provides greater scan diameter than time domain OCT and can be used to guide interventional procedures for larger-caliber coronary abnormalities.

References

1. Syed M, Lesch M. Coronary artery aneurysm: A review. Prog Cardiovasc Dis 1997;40:77–84.
2. Parmar RJ, Uretsky BF. Obliteration of a coronary artery aneurysm with percutaneous transluminal coronary angioplasty and stent placement. Cathet Cardiovasc Diagn 1997;41:51–52.
3. Jokhi PP, Mckenzie DB, O’Kane P. Use of a novel pericardial covered stent to seal an iatrogenic coronary perforation. J Invasive Cardiol 2009;21:E187–E190.
4. Hayat SA, Ghani S, More RS. Treatment of ruptured coronary aneurysm with a novel covered stent. Catheter Cardiovasc Interv 2009;74:367–370.
———————————————————— From the Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom. Disclosures: Supported by the NIHR Biomedical Research Centre, Oxford, U.K. The authors report no financial relationships or conflicts of interest regarding the content herein. Manuscript submitted November 9, 2010 and accepted December 8, 2010. Address for correspondence: Prof. K. M. Channon, Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, OX3 9DU, Oxford, United Kingdom. Email: keith.channon@cardiov.ox.ac.uk