Hiromasa Otake

Evaluation of the peri-strut low intensity area following sirolimus- and paclitaxel-eluting stents implantation: Insights from an optical coherence tomography study in humans ☆

BACKGROUNDnRecent pathological studies have demonstrated that peri-strut low intensity area (PLIA) seen on optical coherence tomography (OCT) imaging represents the presence of fibrinogen and/or extracellular matrix. We sought to assess the clinical prevalence of PLIA and its relation to neointimal proliferation after the implantation of sirolimus- (SES) and paclitaxel-eluting stents (PES) in humans.nnnMETHODSnSeventy patients underwent 6-months follow-up OCT after SES (43 stents) or PES (37 stents) implantation. PLIA was defined as a region around stent struts with homogenous lower intensity than surrounding tissue on OCT images without signal attenuation. The incidence of stent struts with PLIA (+PLIA struts) was calculated as the number of +PLIA struts/number of all struts (%).nnnRESULTSnPES showed a higher incidence of stents with PLIA than SES (86% vs. 58%; p=0.005) with a higher prevalence of +PLIA struts (27.8±21.9% vs. 10.9±11.0%; p=0.0008). SES with PLIA showed a significantly greater neointimal thickness (NIT) than SES without PLIA (p=0.02), while PES showed a similar tendency (p=0.19). In a detailed strut basis analysis, average NIT on +PLIA struts were significantly greater than that on -PLIA struts in both SES and PES. In addition, average NIT was positively correlated with the prevalence of +PLIA struts (SES: Rho=0.73; p<0.0001, PES: Rho=0.58, p=0.0005) in both stents.nnnCONCLUSIONSnThe prevalence of PLIA was significantly higher in PES than in SES. The presence and extent of PLIA might be associated with intimal thickening after 1st-generation DES implantation.

Impact of Diabetes Mellitus on Vessel Response in the Drug-Eluting Stent Era Pooled Volumetric Intravascular Ultrasound Analyses

Background—Exaggerated neointimal hyperplasia is considered as the primary mechanism for increased restenosis in patients with diabetes mellitus (DM) treated with bare-metal stent. However, the vessel response in DM and non-DM treated with different drug-eluting stents (DES) has not been systematically evaluated. Methods and Results—We investigated 3D intravascular ultrasound (postprocedure and 6 to 9 months) in 971 patients (267 with DM and 704 without DM) treated with sirolimus- (n=104), paclitaxel- (n=303), zotarolimus- (n=391), or everolimus- (n=173) eluting stents. Volumetric data were standardized by length as volume index (VI). At postprocedure, lumen VI at the stented segment was significantly smaller in DM than in non-DM, whereas vessel VI was similar between the 2 groups. At follow-up, neointimal obstruction and maximum cross-sectional narrowing (neointimal area/stent area) were not significantly different between the 2 groups with no interaction for the DES type. Consequently, lumen VI was smaller in DM than in non-DM at follow-up. In the reference segments, residual plaque burden at postprocedure was significantly greater in DM than in non-DM, although change in lumen VI was similar between the 2 groups. The arterial responses at the reference segments also showed no interaction for the DES type. Conclusions—DM and non-DM lesions showed similar vessel response in both in-stent and reference segments regardless of the DES type. In the DES era, the follow-up lumen in DM patients seems to be determined primarily by the smaller lumen at postprocedure rather than exaggerated neointima within the stent or plaque proliferation at the reference segments.

Sex differences in neointimal hyperplasia following endeavor zotarolimus-eluting stent implantation.

Inconsistent results in outcomes have been observed between the genders after drug-eluting stent implantation. The aim of this study was to investigate gender differences in neointimal proliferation for the Endeavor zotarolimus-eluting stent (ZES) and the Driver bare-metal stent (BMS). A total of 476 (n = 391 ZES, n = 85 BMS) patients whose volumetric intravascular ultrasound analyses were available at 8-month follow-up were studied. At 8 months, neointimal obstruction and maximum cross-sectional narrowing (CSN) were significantly lower in women than in men receiving ZES (neointimal obstruction 15.5 ± 9.5% vs 18.2 ± 10.9%, p = 0.025; maximum CSN 30.3 ± 13.2% vs 34.8 ± 15.0%, p = 0.007). Conversely, these parameters tended to be higher in women than in men receiving BMS (neointimal obstruction 36.3 ± 15.9% vs 27.5 ± 17.2%, p = 0.053; maximum CSN 54.3 ± 18.6% vs 45.6 ± 18.3%, p = 0.080). There was a significant interaction between stent type and gender regarding neointimal obstruction (p = 0.001) and maximum CSN (p = 0.003). Multivariate linear regression analysis revealed that female gender was independently associated with lower neointimal obstruction (p = 0.027) and maximum CSN (p = 0.004) for ZES but not for BMS. Compared to BMS, ZES were independently associated with a reduced risk for binary restenosis in both genders (odds ratio for women 0.003, p = 0.001; odds ratio for men 0.191, p <0.001), but the magnitude of this risk reduction with ZES was significantly greater in women than men (p = 0.015). In conclusion, female gender is independently associated with decreased neointimal hyperplasia in patients treated with ZES. The magnitude of risk reduction for binary restenosis with ZES is significantly greater in women than in men.

Variability in quantitative and qualitative analysis of intravascular ultrasound and frequency domain optical coherence tomography.

Frequency‐domain optical coherence tomography (FD‐OCT) is an intravascular imaging technique now available in the United States. However, the importance of level of training required for analysis using intravascular ultrasound (IVUS) and FD‐OCT is unclear. The aim of this study was to evaluate inter‐ and intra‐observer variability between expert and beginner analysts interpreting IVUS and FD‐OCT images.

Evaluación de la respuesta vascular al intervencionismo coronario

En las ultimas decadas, la investigacion sobre la respuesta vascular al intervencionismo coronario percutaneo (ICP) ha desempenado un papel fundamental no solo porque mejora el conocimiento de los mecanismos de accion de dicho tratamiento, sino tambien porque aporta una informacion clave para explicar lo que sucede en los pacientes con enfermedad coronaria. Con la reciente introduccion de la tecnologia de stents liberadores de farmacos (SLF), se ha producido un avance extraordinario en la reduccion de la reestenosis, gracias a la inhibicion de la hiperplasia neointimal1,2. Sin embargo, el remodelado vascular tardio y el efecto del borde tras la implantacion de SLF han sido consideradas recientemente como posibles causas de trombosis y reestenosis de stents3,4. En la linea de la investigacion presentada por Garcia-Garcia et al5 en este numero de REVISTA ESPANOLA DE CARDIOLOGIA, la interpretacion de la respuesta vascular que se produce con la actual tecnologia de SLF es imprescindible para poder desarrollar medidas eficaces que contrarresten estos fenomenos, de consecuencias potencialmente catastroficas para el paciente. Ademas, tambien es esencial la valoracion de una metodologia bien establecida y de los conocimientos previamente acumulados en la evaluacion de la respuesta vascular basada en nuestra experiencia con el analisis detallado de la ecografia intravascular (IVUS).