Harumi Kato

Optical Coherence Tomography Findings in Lesions After Sirolimus-Eluting Stent Implantation With Peri-Stent Contrast Staining

Background—We have sometimes noted abnormal angiographic coronary dilatation, <50% of the reference vessel, at the site of sirolimus-eluting stent implantation, suggesting contrast staining outside the stent struts and named this finding peri-stent contrast staining (PSS). Little was known about optical coherence tomography findings of lesions with PSS. Methods and Results—Between May 2008 and March 2010, we performed optical coherence tomography for 90 in-stent restenosis lesions after sirolimus-eluting stent implantation. We found PSS in 20 of the 90 lesions by coronary angiography. The differences in optical coherence tomography findings, including incomplete stent apposition, multiple interstrut hollows (MIH), strut coverage, and thrombus, were compared between lesions with PSS and those without PSS. PSS is defined as contrast staining outside the stent contour extending to >20% of the stent diameter measured by quantitative coronary angiography. MIH is defined as multiple hollows (the maximum depth >0.5 mm) existing between and outside well-apposed stent struts. Both incomplete stent apposition (60.0% versus 10%; P<0.001) and MIH (85.0% versus 25.7%; P<0.001) were frequently observed in lesions with PSS than in lesions without PSS. Among the 20 lesions with PSS, there was only 1 lesion in which we found neither MIH nor incomplete stent apposition, but only minor dissection. Uncovered struts (11.6% versus 3.9%; P=0.001), malapposed struts (2.0% versus 0.0%; P<0.001), and red thrombus (35% versus 10%; P=0.012) were frequently observed in lesions with PSS than in lesions without PSS. Conclusions—PSS might be closely associated with 2 different optical coherence tomography findings, MIH and incomplete stent apposition, in lesions after sirolimus-eluting stent implantation.

The impact of lesion length and vessel size on outcomes after sirolimus-eluting stent implantation for in-stent restenosis

Objectives: We evaluated the predictors of recurrent restenosis and the impact of lesion length and vessel size on outcomes in patients treated with routine sirolimus-eluting stent (SES) implantation for in-stent restenosis (ISR) of bare-metal stent (BMS). Methods: In this study, 250 consecutive patients with 275 lesions after SES implantation for ISR of BMS were enrolled. Follow-up angiogram was obtained in 239 patients with 258 lesions eight months after implantation (follow-up rate: 95.6%). We compared characteristics of patients and lesions between the two groups (the recurrent restenosis group and the no-restenosis group). Results: Recurrent restenosis was angiographically documented in 43 lesions (16.7%). Recurrent restenosis was found in 30.4% with small vessel lesions (reference diameter of less than 2.5 mm, 92 lesions) and 23% with the diffuse type lesions (106 lesions). Seventy-two per cent of patients had a focal pattern of recurrent restenosis. Previously recurrent ISR lesions (odds ratio (OR) 1.94, 95% confidence interval (CI) 0.94 to 4.06, p = 0.05), reference diameter of less than 2.5 mm (OR 2.41, CI 1.05 to 5.41, p = 0.03), diffuse type restenosis (OR 4.48, CI 2.12 to 9.94, p = 0.0001) and dialysis patients (OR 4.72, CI 1.42 to 15.7, p = 0.01) were independent predictors of recurrent restenosis. Conclusions: Small vessels, diffuse type restenosis and dialysis patients were still the predictors of recurrent restenosis in patients treated with SES for ISR of BMS.

Association between tissue characteristics evaluated with optical coherence tomography and mid-term results after paclitaxel-coated balloon dilatation for in-stent restenosis lesions: a comparison with plain old balloon angioplasty

AIMS Morphological assessment of neointimal tissue using optical coherence tomography (OCT) is important for clarifying the pathophysiology of in-stent restenosis (ISR) lesions. The aim of this study was to determine the impact of OCT findings on recurrence of ISR after paclitaxel-coated balloon (PCB) dilatation compared with plain old balloon angioplasty (POBA). METHODS AND RESULTS Between July 2008 and May 2012, we performed percutaneous coronary intervention for 214 ISR lesions using POBA + PCB (146 lesions, PCB group) or POBA only (68 lesions, POBA group). Morphological assessment of neointimal tissue using OCT, including assessment of restenotic tissue structure and restenotic tissue backscatter, was performed. We examined the association between lesion morphologies and mid-term (6-8 months) results including ISR and target lesion revascularization (TLR) rates. Both ISR and TLR rates of lesions with a homogeneous structure were significantly lower in the PCB group than those in the POBA group (ISR: 20.0 vs. 55.6%, P = 0.002, TLR: 12.7 vs. 37.0%, P = 0.019), but there was no difference between the two groups in ISR and TLR rates of lesions with a heterogeneous or layered structure. Both ISR and TLR rates of lesions with high backscatter were significantly lower in the PCB group than those in the POBA group (ISR: 19.8 vs. 52.5%, P < 0.001, TLR: 13.6 vs. 42.5%, P = 0.001), but there was no difference between the two groups in ISR and TLR rates of lesions with low backscatter. CONCLUSION Morphological assessment of ISR tissue using OCT might be useful for identifying ISR lesions favourable for PCB dilatation.