Neointimal Hyperplasia Thickness Research Articles

Serial Comparison of Neointimal Coverage between Two Different Concept Stents: Optical Coherence Tomographic Evaluation

Recently, two different concept drug-eluting stents including biolimus A9-eluting stents (BES) with biodegradablepolymer and everolimus-eluting stents (EES) with durable biocompatible-polymer are available. However, serial comparison of BES and EES on neointimal coverage is not fully investigated. We performed serial evaluation of neointimal coverage at 8 months (BES polymer remained) and 20 months follow-up (BES polymer absorbed) by optical coherence tomography (OCT) for 14 BESs and 10 EESs, and compared uncovered strut proportion (%Uncovered), malapposed strut proportion (%Malapposed) and average neointimal hyperplasia thickness (Ave- NHT), numbers of extra stent lumen (ESL) and multiple interstrut hollow (MIH) calculated by OCT between two DESs, at 8 months and 20 months follow-up, respectively. As a result. at 8 months, Ave-NHT of EES was significantly higher than BES (124 ± 65 E¥m vs 83 ± 47 E¥m, p<0.001) but %Uncovered and %Malapposed were similar between the two groups. At 20 months, %Uncovered and ESL of EES were significantly lower than BES (0.8 ± 5.7% vs 4.8 ± 12.7%, p<0.001 and 0.86 ± 1.28 vs 0.09 ± 0.16, p=0.043) and Ave-NHT of EES was significantly higher than BES (185 ± 88 E¥m vs 90 ± 46 E¥m, P<0.001). In conclusion, EES showed favorable neointimal healing compared to BES

Excellent very early neointimal coverage of bioactive stents by optical coherence tomography

Objectives. In a prospective study, we explored the extent of neointimal coverage of stent struts by optical coherence tomography 14 days following the implantation of bioactive stents in an unselected cohort. Design. We enrolled 15 consecutive patients who underwent bioactive stent implantation. Optical coherence tomography images were obtained at 14-day follow-up. Morphometric analysis, strut coverage, strut apposition, neointimal hyperplasia, and possible thrombosis were evaluated at 1-mm intervals. Binary stent strut coverage was defined as the percentage of covered struts of all analyzed struts. Results. Patients underwent optical coherence tomography examination at an average of 14.5 ± 2.3 days following stent implantation. Mean age was 62 ± 11 years; 86.7% were males; 26.7% diabetic. Three-hundred eighteen cross-sections were analyzed, including 2935 struts, an average of 9.2 ± 3 struts per cross-section. Binary stent strut coverage was 96.3%; the prevalence of malapposed struts 1.8%. No thrombi were detected. Mean neointimal hyperplasia thickness was 71.5 ± 53.7 μm. Conclusions. In the current evaluation by optical coherence tomography at 14-day follow-up after bioactive stent implantation in an unselected cohort, binary stent strut coverage was fairly adequate, and the prevalence of malapposed struts was low.

Assessment of vascular response after drug-eluting stents implantation in patients with diabetes mellitus: an optical coherence tomography sub-study of the J-DESsERT

Even in the drug-eluting stent era, diabetes mellitus (DM) patients have high incidences of restenosis and repeat revascularization after percutaneous coronary intervention. The aim of this study was to compare vascular response after stent implantation between sirolimus-eluting stent (SES) and paclitaxel-eluting stent (PES) by using optical coherence tomography (OCT) in DM patients as well as in non-DM patients. In the Japan-Drug Eluting Stents Evaluation; a Randomized Trial (J-DESsERT), the OCT sub-study enrolled 75 patients who underwent 8 months follow-up imaging after SES or PES implantation. Mean neointimal hyperplasia (NIH) thickness was significantly thinner in SES than PES in the DM group (77 ± 47 vs. 201 ± 114 μm, p < 0.001) and in the non-DM group (84 ± 37 vs. 212 ± 128 μm, p < 0.001). Unevenness of NIH thickness in longitudinal axis was significantly smaller in SES than PES in the DM group (348 ± 191 vs. 726 ± 385 μm, p < 0.001) and in the non-DM group (344 ± 174 vs. 679 ± 314 μm, p < 0.001). The percentage of uncovered struts was significantly greater in SES than PES in the DM group (24 ± 4 vs. 9 ± 14 %, p < 0.001) and in the non-DM group (16 ± 16 vs. 3 ± 4 %, p = 0.002). Compared with PES, SES showed more potent NIH inhibition in DM patients as well as in non-DM patients.

Different serial changes in the neointimal condition of sirolimus-eluting stents and paclitaxel-eluting stents: an optical coherence tomographic study

Detailed long-term changes of the neointima in sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES) are still unclear. We consecutively enrolled 14 patients (18 SES) and 12 patients (13 PES) who underwent optical coherence tomography (OCT) serially at eight months and 18 months after stent implantation. For 18 SES and 13 PES, OCT was used to visualise 2,486 and 1,361 stent struts at the eight-month and 2,199 and 1,309 stent struts at the 18-month follow-up, respectively. The OCT parameters, including incidence of uncovered and malapposed struts (uncovered and malapposed percentage), average neointimal hyperplasia thickness (NIH thickness) and %NIH volume obstruction, which was defined as ([mean NIH area*stent length]/[mean stent area*stent length])100, and qualitative analysis of the neointima were compared between SES and PES and also compared between the eight- and 18-month follow-up for SES and PES, respectively. The uncovered and malapposed percentage was significantly higher in SES than PES at the eight- and 18-month follow-up, and the NIH thickness and %NIH volume obstruction were lower in SES than PES at both follow-ups. The uncovered and malapposed percentage decreased in both SES and PES between the eight- and 18-month follow-up. Percent NIH volume obstruction and NIH thickness in SES significantly increased from the eight- to 18-month follow-up; however, those parameters significantly decreased in PES. The incidence of high signal with peri-strut low-intensity areas increased in SES but decreased in PES from the eight- to 18-month follow-up. Uncovered and malapposed struts were reduced in both SES and PES, while the neointimal hyperplasia and qualitative changes showed different patterns.

Neointimal coverage of zotarolimus-eluting stent at 1, 2, and 3 months' follow-up: an optical coherence tomography study.

Incomplete neointimal coverage and malapposed struts after stenting are associated with increased risk of stent thrombosis. We aimed to evaluate neointimal coverage early after Resolute zotarolimus-eluting stent (R-ZES) implantation using optical coherence tomography (OCT). A total of 20 patients with de novo native coronary lesions with R-ZES were enrolled. Among these patients, 20 stented lesions in 19 patients were evaluated at 1, 2, and 3 months after R-ZES implantation. The strut apposition and neointimal coverage were evaluated by OCT. Neointimal hyperplasia (NIH) thickness and percentage of covered struts and the proportion of incompletely apposed struts were measured at 1-mm intervals. The mean percentages of covered stent struts were over 85 % within 3 months (88.4 ± 6.3 % at 1 month, 95.5 ± 5.5 % at 2 months, 93.6 ± 3.5 % at 3 months). The percentages of incompletely apposed struts were not significantly different among the groups (4.4 ± 4.2 % at 1 month, 1.9 ± 1.9 % at 2 months, 3.1 ± 2.2 % at 3 months, p = 0.51). Mean NIH thickness (38.9 ± 8.1 μm at 1 month, 70.6 ± 18.8 μm at 2 months, 54.1 ± 5.9 at 3 months, p = 0.0016) was thickest in the 2 months group. Most of all OCT findings within 2 months demonstrated neointimal coverage with low signal intensity. The neointimal coverage of ZES-R was over 85 % within 3 months. These data may support shorter requirement of dual antiplatelet therapy duration with R-ZES.

Side branch healing patterns of the Tryton dedicated bifurcation stent: a 1-year optical coherence tomography follow-up study.

The bare-metal Tryton Side Branch (SB) Stent™ (Tryton Medical, Durham, NC, USA) is used with a drug-eluting stent (DES) in the main branch (MB) to treat bifurcation lesions. It is argued that a drug-eluting Tryton-version is needed to improve clinical outcomes, although previous registries have shown good clinical results. More insights in neo-intimal hyperplasia (NIH) growth patterns of the Tryton treatment strategy are needed to decide if and where to drug-coat the stent. Ten patients returned for follow-up angiography (mean follow-up time 393 ± 103 days) and optical coherence tomography (OCT) pullbacks from the MB were obtained in all patients and from the SB in six patients. A per-strut analysis showed an uncovered strut rate of 0.7 % and an incompletely-apposed strut rate of 0.8 %. Most incompletely-apposed struts were found at the bifurcation region, in the luminal half facing towards the SB. Mean NIH thickness in the proximal MB, distal MB and SB were 0.14 ± 0.11, 0.19 ± 0.11, and 0.34 ± 0.19 mm, respectively, with a variety of growth patterns observed in the SB. We found good vascular healing of the DES in the MB, while healing was less favourably in the SB part. Furthermore, we observed a variety of NIH growth patterns in this SB part and more studies are needed to investigate the relation between growth patterns and clinical outcomes.

Temporal course of neointimal hyperplasia following drug-eluting stent implantation: a serial follow-up optical coherence tomography analysis.

We sought to evaluate the temporal course of neointimal hyperplasia (NIH) after drug-eluting stent (DES) implantation, using serial optical coherence tomography (OCT). We identified 89 DES (82 patients) that had at least three consecutive cross-sections with a mean NIH thickness >100 µm on first follow-up OCT. Qualitative and quantitative changes in NIH were then assessed at a second follow-up OCT. NIH regression and progression were defined as a decrease or increase in mean NIH cross-sectional area >0.2 mm2, respectively, between the two studies. Between the first and second OCT there was a decrease in NIH in 29 lesions (32.6%), and an increase in NIH in 37 lesions (41.6%). Compared to patients with neointimal progression, those with regression showed lower levels of high sensitivity C-reactive protein (hsCRP) (p = 0.036) and higher levels of high-density lipoprotein (p = 0.012). Between the first and the second OCT, there were no significant changes in NIH morphologic patterns in 67 (75.3%) of 89 DES. In lesions with NIH regression, the evolution of heterogeneous to homogeneous neointima was observed, while the evolution of heterogeneous or homogeneous to layered neointima or the evolution of heterogeneous, homogeneous, or layered neointima to neoatherosclerosis was detected in lesions with NIH progression (p < 0.001). The hsCRP level at index procedure was significantly associated with neointimal regression in multivariate model (odds ratio 0.891, 95% confidence interval 0.796-0.999, p = 0.048). During late follow-up, OCT shows both NIH progression and regression that are paralleled by qualitative changes indicating increasing stability (in regression) and increasing instability (in progression).

Neointimal coverage and vasodilator response to titanium-nitride-oxide-coated bioactive stents and everolimus-eluting stents in patients with acute coronary syndrome: insights from the BASE-ACS trial

Incomplete stent endothelialization is associated with late and very late stent thrombosis. In a post hoc analysis of the BASE-ACS trial, we sought to assess neointimal coverage and coronary flow reserve (CFR) 9 months after implantation of titanium-nitride-oxide-coated bioactive stents (BAS) versus everolimus-eluting stents (EES) in patients with acute coronary syndrome (ACS). In the BASE-ACS trial, 827 patients with ACS were randomized to receive either BAS or EES. In the current study, we examined neointimal growth and strut coverage by optical coherence tomography and CFR by trans-thoracic echocardiography in 28 consecutive non-diabetic patients with the culprit lesion in the left anterior descending coronary artery. The primary endpoints were binary stent strut coverage and CFR at 9-month follow-up. A total of 13 patients were included in the BAS group (2,033 struts); 15 in the EES group (2,898 struts). Binary stent strut coverage was higher and malapposed struts lower with BAS versus EES (99.4 vs 89.2, and 0.2 vs 4.6%, respectively, p < 0.001 for both). Neointimal hyperplasia thickness was greater with BAS versus EES (274.2 vs 100.1 μm, respectively, p < 0.001). CFR was lower with EES versus BAS (2.2 ± 0.8 vs. 3.0 ± 0.5, respectively, p = 0.001). Abnormal CFR (<2.5) were detected in 10 patients in the EES group versus one in the BAS group (p = 0.002). The current study demonstrated that in patients with ACS, BAS resulted in improved neointimal stent strut coverage and better coronary vasodilator function as compared with EES at 9-month follow-up.

Evaluation of the novel novolimus-eluting bioresorbable vascular scaffold for the treatment of de novo coronary artery stenosis: serial optical coherence tomography analysis of the DESolve NX study

Purpose: The DESolve system is a novel Poly-L-Lactide (PLLA)-based scaffold, designed to provide both temporary vessel support along with neointimal suppression, followed by full bioresorption between one and two years. In the present study, we aim to present the first serial optical coherence tomography (OCT) evaluation of the novel PLLA-based novolimus-eluting DESolve bioresorbable scaffold investigated in the DESolve NX study. Methods: The DESolve NX study enrolled 126 patients with single de novo native coronary lesions at 13 sites. A serial (baseline and 6-month follow-up) analysis of the first 25-patient subset who underwent OCT examination will be presented. All OCT images were analyzed by an independent core laboratory at 0.6-mm interval. At baseline, lumen, scaffold, plaque prolapse and incomplete scaffold apposition (ISA) areas were determined. At follow-up, serial changes in lumen and scaffold dimensions and degree of neointimal hyperplasia (NIH) formation on top of the struts will be assessed. Frequency of covered struts and NIH thickness on top of each covered strut will also be examined. OCT imaging end-points were scaffold expansion and structural integrity post-procedure and neointimal obstruction and degree of strut coverage at six-month follow-up. Results: At baseline, overall adequate scaffold expansion (93.75±9.21%) was obtained. A mean of 30.44±5.16 cross-sections were analyzed per scaffold. Mean lumen and scaffold areas measured 6.80±1.35 mm2 and 6.95±1.32 mm2, respectively, with a minimum scaffold area post-procedure of 5.71±1.15 mm2. In average, plaque prolapse accounted for a very small area of lumen reduction post-procedure (0.03±0.02 mm2). ISA was detected at baseline in 9 (36%) scaffolds, but it was in average very small (0.07±0.13 mm2). A total of 9,871 struts were analyzed at baseline, and the frequency of malapposed struts per patient was 0.43±0.98%. All 25 patients have already completed 6-month OCT evaluation, and the images are currently under analysis. The complete serial OCT results will be available at the meeting. Conclusions: The novel PLLA-based novolimus-eluting bioresorbable scaffold demonstrated an excellent acute performance, tolerating very good expansion with virtually no structural deformity concerns. Good vessel wall conformability was also demonstrated, resulting in minimal areas of scaffold malapposition. Six-month OCT analysis is being conducted and will be presented at the meeting.

Different neointimal response to overlapping segments between everolimus eluting stents and sirolimus eluting stents -optical coherence tomographic study

Purpose: Although overlapping coronary stents in long lesions by percutaneous coronary intervention are common, some recent clinical studies have revealed an adverse neointimal response to overlapping segments of drug eluting stents due to increased drug and polymer toxicity. Thus, the purpose of this study was to evaluate the difference of neointimal response to overlapping segments of Everolimus- Eluting Stents (EES) and Sirolimus-Eluting Stents (SES) by Optical Coherence Tomography (OCT). Methods: Thirty-seven consecutive lesions treated with overlapping stents (20 EES and 17 SES) were analyzed by OCT. We compared the OCT parameters including the rate of uncovered or malapposed struts, percentage Neointimal Hyperplasia (%NIH) and strut-level neointimal thickness between overlapping segments of EES and those of SES. Heterogeneity index (sum of (max NIH thickness – minimum one) at each cross-section/number of cross-sections) was also calculated. Results: A total of 2984 struts in 277 cross-sections of 37 stented segments were analyzed. At overlapping segments, the rate of uncovered or malapposed struts, %NIH, strut-level neointimal thickness and heterogeneity index in EES were significantly lower than those in SES (Table). ![Figure][1] Conclusions: According to our study assessed by OCT, EES showed more favorable neointimal response to the overlapping segments than SES. These findings should be considered when deploying overlapping stents in long lesions. [1]: pending:yes

Comparison of Early Strut Coverage Between Zotarolimus- and Everolimus-Eluting Stents Using Optical Coherence Tomography

There have been no optical coherence tomographic (OCT) data directly comparing the pattern of strut coverage between the 2 second-generation drug-eluting stents in the early period. The aim of this prospective study was to evaluate early strut coverage using optical coherence tomography 3 months after Resolute zotarolimus-eluting stent (ZES-R) or everolimus-eluting stent (EES) implantation in de novo coronary artery lesions. A total of 40 patients who were suitable for the OCT procedure and consented to the study protocol were randomized 1:1 to receive either ZES-R or EES. Among these patients, 35 stented lesions (18 ZES-R, 17 EES) in 34 patients were evaluated by optical coherence tomography immediately and 3 months after stent implantation. Neointimal hyperplasia thickness, percentage of uncovered struts, and the proportion of malapposed struts were measured at 1-mm intervals. An uncovered strut was defined as having a neointimal hyperplasia thickness of 0 μm. At the 3-month OCT evaluation, mean neointimal hyperplasia thickness (ZES-R vs EES 74 ± 41 vs 75 ± 35 μm, p = 0.89) and mean percentage of uncovered struts (ZES-R vs EES 6.2 ± 6.9 vs 4.7 ± 5.1%, p = 0.62) were not significantly different between the groups. The percentage of malapposed struts was also similar between the groups (0.7 ± 2.2% for ZES-R and 0.7 ± 1.7% for EES, p = 0.64). Thrombi were documented in 3 stents (1 [5.6%] in a ZES-R vs 2 [11.8%] in EES, p = 0.60). In conclusion, early stent strut coverage on the basis of serial OCT evaluation was comparable between ZES-R and EES 3 months after stent implantation.

Evaluation of long‐term follow‐up with neointimal coverage and stent apposition after sirolimus‐eluting stent implantation by optical coherence tomography

Late stent thrombosis related to delayed endothelialization is a major concern after drug-eluting stent (DES) implantation. The long-term vascular response towards DES implantation remains unclear. Optical coherence tomography (OCT) is a high-resolution imaging modality which provides new opportunities for evaluating neointimal coverage and stent strut apposition after stent implantation. Fifty two patients who accepted 64 sirolimus-eluting stents (SESs, Cypher Select) were enrolled in the study. The OCT procedure was performed in 20 patients at 12 months (group 1), 17 patients at 24 months (group 2), and 15 patients at 48 months (group 3) after SESs implantation, respectively. The neointimal hyperplasia (NIH) thickness and stent strut apposition were assessed at 1-mm interval, and the presence of thrombus was observed in each stent. The NIH thickness was significantly higher at 48 months than that of 12 months (0.1694 ± 0.1455 mm in G3 vs. 0.1455 ± 0.1373 mm in G1, P < 0.01) and 24 months (0.1514 ± 0.1296 mm in G2, P <0.01) after SESs implantation, but no significant difference existed between that of 12 months and 24 months (P > 0.05). Longer follow-up time was associated with significant decrease in the prevalence of uncovered struts (17.3% in group 1 vs. 8.8% in group 2 vs. 2.6% in group 3, P < 0.01) and malapposed struts (14.2% in group 1 vs. 10.3% in group 2 vs. 4.7% in group 3, P < 0.01). The incidence of intracoronary thrombus steadily decreased from 3.6% at 12 months to 2.4% at 24 months, and to 0.8% at 48 months (P < 0.01). Neointimal growth continued for as long as 48 months after SES implantation. NIH thickness increased insignificantly from 12 to 24 months, but markedly increased at 48 months after stent implantation. Late neointimal growth was accompanied by a higher rate of covered struts and lower rate of malapposed stent struts.

Initial findings of impact of strut width on stent coverage and apposition of sirolimus‐eluting stents assessed by optical coherence tomography

We investigate the influence of stent design on stent coverage at 6-9 months after sirolimus eluting stent (SES) implantation using optical coherence tomography (OCT). Although some reports suggest that stent design may correlate with stent coverage of stent struts, there were few detailed data whether stent design impact on stent coverage in the same drug-eluting stent. A total of 21 SESs (15 patients), who had implanted 2.5, 2.75, and 3.0 mm stents, underwent OCT at 6-9 months after stent implantation. SES is constructed by two different strut width-components; narrow strut width parts (59 μm) and wide strut width parts (115 μm). Thus, we divided stent struts of SESs into two groups: narrow strut width parts (narrow group) and wide ones (wide group). We compared the incidence of incomplete apposed struts, uncovered struts, and neointimal hyperplasia (NIH) thickness between the two groups. We could detect 2,948 struts (narrow group consisted of 1,132 struts and wide group consisted of 1,816 struts). Incidence of uncovered struts in the narrow group was significantly lower than in the wide group (30.2% vs. 40.8%, P < 0.001), and NIH thickness in the narrow group was significantly greater than in the wide group (127.5 ± 93.4 μm vs. 118.6 ± 81.4 μm, P = 0.03). Stent design, especially strut width, affects stent coverage of SES. The narrow strut may avoid the absence of stent coverage in SES, which correlates with stent thrombosis.

Stent strut coverage of titanium-nitride-oxide coated stent compared to paclitaxel-eluting stent in acute myocardial infarction: TITAX-OCT study

Drug-eluting stents (DES) have reduced the rate of restenosis but recent studies have raised concern over the risk of late stent thrombosis (LST). Incomplete stent endothelialization and delayed vascular healing have been associated with LST. The titanium-nitride-oxide coated bio-active stent (BAS) has shown promising results in patients with acute coronary syndromes, but there is little long-term optical coherence tomography (OCT) data comparing BAS with DES. The TITAX-AMI trial is a prospective, randomized, multicenter trial comparing BAS to paclitaxel-eluting stent (PES) in 425 patients with acute myocardial infarction. A total of 18 patients (9 per group) with no major cardiac events during follow-up, were enrolled in this substudy >36 months (mean 47 months) after stent implantation. Quantitative coronary angiography was performed and stent strut endothelialization and vascular healing were assessed with OCT. The binary stent strut coverage was significantly higher in the BAS group compared with the PES group (99.6 vs. 89.2%, p < 0.001) and there were less malapposed struts in the BAS group (0.2 vs. 13.8%, respectively, p < 0.001). The neointimal hyperplasia (NIH) thickness (266 ± 166 vs. 126 μm ± 126 μm, p < 0.001) and percentage of NIH area (26.2 vs. 7.6%, p < 0.001) were greater in the BAS group than in the PES group. Late incomplete endothelialization was not uncommon after PES implantation. Stents in the BAS group were completely endothelialized. This difference may contribute to the more common LST after PES implantation in the TITAX-AMI trial.

Abstract 9819: Comparison of Optical Coherence Tomography and Histopathology Findings Following Paclitaxel-Coating Balloon in Porcine In-Stent Stenosis Model

Background: Paclitaxel-Coating balloon (PCB) has shown efficacy for treatment of coronary artery disease. Optical coherence tomography (OCT) is a promising endovascular imaging devise and has been reported to have a high correlation with histomorphometric measurement. However, the association of in-stent stenosis (ISR) by OCT and histopathology response is still not fully addressed. The current study was designed to compare the OCT and histopathological findings following PCB treatment in a porcine ISR model. Materials and Methods: Thirty-two coronary arteries (LAD: n=12, LCX: n=11, RCA: n=9) of 24 Yorkshire pigs were assigned to two (2) groups randomly. PCB (SeQuent, length 20mm, n=16) or non-coating balloon (NCB, length 20mm n=16) were inflated for 60 seconds with B:A 1.2:1 followed by BMS (length 12mm) implantation (S/A 1.5:1) within the target region. At 28 days, animals underwent OCT and histopathology evaluation. Results: There were no significant differences between groups among parameters measured by OCT. The thickness of neointimal hyperplasia on stent strut and the percent of ISR were 585 ± 277 μ m, 46.8 ± 19.0 % for PCB, and 661 ± 237 μ m, 52.4 ± 15.3 % for NCB (p=NS, respectively). However, inflammation (PEB: 3.40 ± 0.84, NCB: 2.27 ± 1.18, p=0.003) and fibrin deposition scores (PCB: 2.31 ± 0.93, NCB: 0.81 ± 0.86, p&lt;0.001) were significantly higher in PCB compared to NCB. The OCT ISR% was positively correlated with inflammation score (PCB: r=0.62, and NCB: r=0.85; p&lt;0.05 respectively). Interestingly, fibrin deposition score only in PCB was negatively correlated with the OCT ISR% (r=-0.68, p=0.005). OCT also showed an uncovered (33.3%) and insufficient non-uniformed neointima (13.3%) in PCB group (p=0.008 vs NCB). Conclusions: OCT can be used as a valuable imaging tool to evaluate vessel wall histopathological changes in vivo. The higher inflammation and fibrin deposition scores in PCB may indicate a delayed healing response in the current experimental setting.

Paclitaxel-coated balloon study: quantitative coronary angiography and optical coherence tomography evaluation in a swine in-stent stenosis model

BackgroundDrug coated balloons (DCBs) have shown efficacy for treatment of coronary artery disease. In PEPCAD II ISR trial, paclitaxel-coated balloon (PCB) reduced in-stent restenosis (ISR) compared with paclitaxel-eluting stent (PES)....

Optical coherence tomographic comparison of neointimal coverage between sirolimus- and resolute zotarolimus-eluting stents at 9 months after stent implantation

The Resolute zotarolimus-eluting stent (ZES-R) has a thinner stent strut with biocompatible polymer than first generation drug-eluting stents. However, minimal optical coherence tomography (OCT) data exists about vascular responses after ZES-R implantation. This study investigated OCT findings in ZES-R implantation and compared them to those in sirolimus-eluting stent (SES) implantation. A total of 123 lesions (43 ZES-R and 80 SES) in 111 patients were evaluated with OCT at 9 months after stent implantation. Strut apposition, neointimal hyperplasia (NIH) thickness, and stent coverage on each stent strut were evaluated. Mean NIH thickness was significantly greater in ZES-R-treated lesions than in SES-treated lesions (166 ± 73 μm vs. 96 ± 63 μm, respectively, P < 0.001). The percentage of uncovered strut was significantly lower in ZES-R-treated lesions than in SES-treated lesions (4.4 ± 4.8% vs. 10.3 ± 13.2%, respectively, P = 0.05). The percentage of malapposed struts was also significantly lower in ZES-R-treated than in SES-treated lesions (0.1 ± 0.4% vs. 1.5 ± 4.2%, respectively, P = 0.002). Intracoronary thrombus was less frequently detected in ZES-R-treated lesions (4.7% vs. 30.0%, respectively, P = 0.001). ZES-R showed a lower incidence of uncovered or malapposed stent struts and intracoronary thrombus than SES at 9-month follow-up OCT examination. Compared with SES, ZES-R may elicit more favorable vascular responses at the expense of an increased neointimal proliferation.

Evaluation of neointimal coverage and apposition with various drug-eluting stents over 12 months after implantation by optical coherence tomography

BackgroundOptical coherence tomography (OCT) is an imaging technology with high resolution which provides new opportunities for evaluating the vascular healing reaction after stent implantation. We used OCT to compare neointimal coverage and stent strut apposition with different types of drug-eluting stent (DES) at more than 12months follow-up. MethodsFifty five patients who accepted 72 DESs (19 sirolimus-eluting stents [SES, Cypher Select], 27 paclitaxel-eluting stents [PES, Taxus Liberte], 26 zotarolimus-eluting stents [ZES, Endeavor]) were enrolled in our study. OCT was performed at 12–18months after stent implantation. The neointimal hyperplasia (NIH) thickness and stent strut apposition at 1-mm interval and the presence of thrombus in each stent were observed. ResultsThe average NIH thickness (0.1806±0.1726mm in SES vs. 0.2558±0.2187mm in PES vs. 0.2983±0.2567mm in ZES, p<0.001) and percentage of NIH area (17.21±14.05% in SES vs. 23.09±14.53% in PES vs. 28.73±20.47% in ZES, p=0.002) were significantly greater in ZES than in other DESs. The prevalence of uncovered struts (8.96% in SES vs. 6.19% in PES vs. 2.98% in ZES, p<0.01) and malapposed struts (6.36% in SES vs. 2.32% in PES vs. 1.69% in ZES, p<0.01) was significantly lower in ZES than in other DESs. Thrombus was less frequently observed in ZES than in other DESs (SES 1.70% vs. PES 0.83% vs. ZES 0.17%, p<0.01). ConclusionsCompared with SES and PES, ZES showed lower prevalence of uncovered struts and malapposed struts at more than 12months follow-up.

Favorable neointimal coverage in everolimus-eluting stent at 9 months after stent implantation: comparison with sirolimus-eluting stent using optical coherence tomography

Recent studies reported favorable angiographic and clinical outcomes after everolimus-eluting stent (EES) implantation. However, there were no studies to assess vascular responses after EES implantation using optical coherence tomography (OCT). Therefore, the OCT findings in EES were investigated and compared with those in sirolimus-eluting stent (SES). Follow-up OCT studies were performed in 110 lesions (40 EES and 70 SES) of 104 patients at 9 months after stent implantation. The strut apposition, neointimal hyperplasia (NIH) thickness and stent coverage on each stent struts were evaluated. The mean NIH thickness was significantly greater in EES-treated lesions than in SES-treated lesions (115 ± 52 μm vs. 89 ± 58 μm, P = 0.001, respectively). The percentage of uncovered strut was significantly smaller in EES-treated lesions than in SES-treated lesions (4.4 ± 4.7% vs. 10.5 ± 12.7%, P = 0.016, respectively). There was no significant difference in the percentage of malapposed strut between the two groups (0.4 ± 0.8% in EES vs. 1.7 ± 4.5% in SES, P = 0.344). The incidence of intracoronary thrombus was significantly lower in EES-treated lesions than in SES-treated lesions (5.0% vs. 34.3%, P < 0.001, respectively). EES showed a significantly lower incidence of uncovered stent struts and intracoronary thrombus than SES in 9-month follow-up OCT examination. Compared to SES, EES might have more favorable vascular responses after stent implantation.

Spatial distribution of neo-intimal hyperplasia 6 months after zotarolimus-eluting stent implantation, analysed by optical coherence tomography

Optical coherence tomography is a high-resolution imaging technology that allows in vivo assessment of neointimal hyperplasia and strut coverage after coronary stenting. Assessment of spatial distribution of healing, 6 months after zotarolimus-eluting stent implantation. Forty-two zotarolimus-eluting stents were monitored by optical coherence tomography 6 months after implantation. Mean neointimal strut coverage thickness and percentage of neointimal hyperplasia were measured every millimetre. Non-covered strut ratios were assessed on each slice. In addition, the spatial distribution of neointimal hyperplasia and strut coverage were analysed longitudinally on five stent segments and axially on each slice. There were no clinical events at 6 months under dual antiplatelet therapy. The optical coherence tomography analysis showed a mean neointimal hyperplasia thickness of 333±147μm and neointimal hyperplasia obstruction of 36.1±12.3%. The percentage of covered struts at 6 months was very high (98.9%). Only 6/745 slices analysed (0.8%) had non-covered strut ratios exceeding 30%. There was no significant heterogeneity in either longitudinal or axial neointimal hyperplasia distribution. No thrombi were observed. This optical coherence tomography study found relatively constant neointimal hyperplasia thickness, regardless of the zotarolimus-eluting stent length or diameter. This spatially homogeneous neointimal hyperplasia was associated with near-total coverage of all struts, 6 months after implantation.