The role of integrated backscatter intravascular ultrasound in characterizing bare metal and drug-eluting stent restenotic neointima as compared to optical coherence tomography.

BACKGROUND: To evaluate the role of integrated backscatter intravascular ultrasound (IB-IVUS) in assessing the morphology of neointima in bare-metal stent (BMS) and drug-eluting stent (DES) restenosis as compared to the gold-standard, optical coherence tomography (OCT). METHODS: A total of 120 cross-sections were evaluated by IB-IVUS and OCT at five cross-sections from 24 patients (24 lesions): at the minimal lumen area (MLA) and at 1 and 2mm proximal and distal to the MLA site in 24 lesions (9 treated with DES and 15 treated with BMS). IB-IVUS and OCT findings were analyzed according to the time at which restenosis was identified (early <12 months and late ≥12 months) and the stent type. RESULTS: IB-IVUS was found to correctly characterize the neointima of both BMS and DES in-stent restenosis (ISR) as compared to OCT. The overall agreement between the pattern of ISR neointima by IB-IVUS and that by OCT was excellent (kappa=0.85, 95% CI 0.76-0.94). Late DES ISR was characterized by more non-homogeneous, low backscatter and lipid-laden neointima, as compared to the BMS equivalent (BMS vs. DES, 45.0% vs. 80.0%, p<0.01; 51.7% vs. 85.0%, p=0.008; 33.3% vs. 65.0%, p<0.01, respectively). CONCLUSIONS: IB-IVUS assessment of the ISR neointima pattern appears to provide similar information as the gold-standard OCT in patients with stable angina. Both modalities suggested that late DES restenosis is characterized by a non-homogeneous lipid-laden neointima.

Calcification analysis by intravascular ultrasound to define a predictor of left circumflex narrowing after cross-over stenting for unprotected left main bifurcation lesions.

OBJECTIVES: The aim of this study was to identify predictors of significant LCx-ostium compromise after distal unprotected left main coronary artery (ULMCA) stenting on the basis of baseline intravascular ultrasound (IVUS). BACKGROUND: Provisional single-stenting is considered as the default strategy for non-true bifurcation lesions in ULMCA. However, in certain cases, left circumflex artery (LCx)-ostium stenting is necessary. METHODS: A total of 77 patients underwent percutaneous coronary intervention with drug-eluting stents for non-true bifurcation lesions in ULMCA and had IVUS evaluation. Pre-procedural IVUS was performed to measure cross-sectional areas at the following segments: left main trunk, left anterior descending artery (LAD)-ostium. Post-stenting-narrowing at the circumflex ostium (PSN-LCx) was defined as the presence of more than 50% diameter stenosis at the LCx-ostium as determined by quantitative coronary angiography analysis. RESULTS: PSN-LCx occurred in 27 (35%) patients. The presence of calcified plaque at the culprit lesion as identified by IVUS was more frequently observed in the PSN-LCx group as compared to the non-PSN-LCx group (81.5% vs. 22.0%, p<0.001). Calcium arc in the PSN-LCx group was significantly greater than that in the non-PSN-LCx group (118.1°±69.9° vs. 36.9°±63.0°, p<0.001). On multivariable analysis, a calcium arc>60° was an independent predictor of PSN-LCx (odds ratio: 5.12, 95% confidence interval: 1.21-25.01, p=0.03). CONCLUSIONS: The presence of calcified plaque at the culprit lesion appears to be one of the factors involved in LCx-ostial compromise in non-true bifurcation ULMCA lesions, especially when the calcium arc is >60°.

A case of Kawasaki's disease with extensive calcifications needing rotational atherectomy with a 2.5mm burr.

This case report demonstrates a unique strategy requiring a 2.5 mm burr to treat in-stent restenosis of an originally underexpanded stent, implanted in a heavily calcified lesion within a giant aneurysm by Kawasaki disease. Despite our procedural success, it should be emphasized that stent implantation in undilatable lesions should be avoided. When an angiographically calcified lesion within an ectatic segment is observed in a patient with Kawasaki disease, it is recommended that the operator evaluates in detail the severity and location of calcification using intravascular ultrasound imaging and pays meticulous attention to lesion preparation.