Bare metal stent implantation for in-stent restenosis with a drug-eluting stent.

Following the positioning of a bare metal stent (BMS) implant, a yellow plaque is healed with a reduction of the color grade and thrombogenicity, i.e. vulnerability by angioscopy in the chronic phase ("plaque sealing" of BMS; the "whitening effect" of BMS). However, we have reported that thrombus and yellow plaque increases at the drug-eluting stent (DES) site. A 71-year-old man underwent percutaneous coronary intervention using two DESs for a severe stenotic lesion in his right coronary artery. Follow-up coronary angiography (CAG) showed in-stent restenosis (ISR) at the stent-overlap site. We performed traditional balloon angioplasty, but follow-up CAG showed ISR again at the same position as the first restenosis. In angioscopic findings, the normal vessel wall was white, but the site of DES implantation was yellow and a yellow, soft, swelling neointimal proliferation-like vulnerable plaque was observed at the restenotic site. In expectation of the "whitening effect" of BMS, we implanted a new BMS. As anticipated, follow-up CAG showed no restenosis. Moreover, the angioscopic findings indicated a clean, white, neointimal proliferation-like stable plaque at the BMS implant site in the yellow vulnerable area of DES. The "BMS in DES" therapy should be considered one of the strategies for ISR of DES.

Detection of myocardial ischemia using 64-slice MDCT.

BACKGROUND: The purpose is to investigate the ability of 64-slice multidetector computed tomography (MDCT) at rest in detecting myocardial ischemia, conventionally depicted by myocardial perfusion scintigraphy (MPS). METHODS AND RESULTS: In 75 patients with suspected coronary artery disease, cardiac CE-MDCT at rest and stress/rest MPS were performed. The 2D myocardial images were reconstructed in diastolic and systolic phases using raw data from coronary computed tomography (CT) angiography. CT numbers in the myocardium were used as an estimate of myocardial enhancement. The myocardium was shown using a color scale that depicts faint low-density areas more clearly than gray scale. The variation in myocardial enhancement was evaluated at systole and diastole for those segments depicted as ischemia on MPS. A pattern of transient endocardial hypo-enhancement at systole and normal enhancement at diastole as the ischemic pattern on CT myocardial image was defined. MPS diagnosed myocardial ischemia in 40 of 75 patients. Use of the ischemic pattern on CT images distinguished patients with and without ischemia with a sensitivity of 90%, specificity of 83%, positive predictive value of 86% and negative predictive value of 88%. CONCLUSIONS: CT myocardial imaging at rest demonstrates a characteristic enhancement pattern for ischemia. This has potential as a non-invasive method for detecting ischemia.