Rotational atherectomy ablation for an unexpandable stent under the guide of IVUS: A case report

A State-Of-The-Art Review on Coronary Artery Border Segmentation Algorithms for Intravascular Ultrasound (IVUS) Images

Intravascular Ultrasound images (IVUS) is a useful guide for medical practitioners to identify the vascular status of coronary arteries in human beings. IVUS is a unique intracoronary imaging modality that is used as an adjunct to angioplasty to view vessel structures using a catheter with high resolutions. Segmentation of IVUS images has always remained a challenging task due to various impediments, for example, similar tissue components, vessel structures, and artifacts imposed during the acquisition process. Many researchers have applied various techniques to develop standard methods of image interpretation, however, the ultimate goal is still elusive to most researchers. This challenge was presented at the MICCAI- Computing and Visualization for (Intra)Vascular Imaging (CVII) workshop in 2011. This paper presents a major review of recently reported work in the field, with a detailed analysis of various segmentation techniques applied in IVUS, and highlights the directions for future research. The findings recommend a reference database with a larger number of samples acquired at varied transducer frequencies with special consideration towards complex lesions, suitable validation metrics, and ground-truth definition as a standard against which to compare new and current algorithms.

Pericardial Tamponade Caused by Rotational Atherectomy Ablation Grinding Through a Barrier Stent Protruding From the Diagonal Artery: A Case Report

Rotational atherectomy (RA) has been described in case reports to be effective in ablating under-expanded stents. We present a case of calcified bifurcation lesion percutaneous coronary intervention (PCI), in which the branch stent protruding into main branch blocked the balloon getting through, and the following RA led to pericardial tamponade. The first stent was deployed from the proximal of left anterior descending artery (LAD) to the proximal of diagonal for an 80-year-old man who suffered from non-ST-elevation myocardial infarction to make a Culotte dual stent PCI. The operator failed to make balloon get through the struts protruding into LAD lumen anyway. After RA drill through the LAD lumen, it showed an excellent angiographic outcome. Stent deployment in LAD was successful, but pericardial tamponade occurred in a short time. After pericardiocentesis was performed under fluoroscopic guidance, the patient was uneventful. After 1 year, the follow-up coronary computed tomography (CT) angiography showed no in-stent restenosis, stent fracture or disrupted struts protruding outside of the vessel’s outline of LAD and the first diagonal (D1). This case shows stents’ RA could be dangerous in grinding across the stents’ lateral hole in an unsymmetrical lumen. Although RA could be a useful remedy in the situation of under-expansion of implanted stents, the debulking should be performed for longitudinal stent ablation and cautiously performed for bifurcation lesion in which the protruding stents from side branch were unsymmetrically blocking the path.

Stentablation with Rotational Atherectomy for the Management of Underexpanded and Undilatable Coronary Stents

Stentablation with rotational atherectomy for the management of undilatable underexpanded coronary stents is a unique application associated with excellent periprocedural and in-hospital outcomes. Data regarding long-term outcomes remains limited, however the procedure appears to be associated with high prevalence of target lesion revascularization. Given the complexity of such lesions and few available interventional remedies; it is a reasonably safe and widely available approach of which operators should be aware. When stentablation is performed, the principles which guide contemporary rotational atherectomy and percutaneous coronary intervention, including intravascular imaging, should be applied.