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Publications (14)43.78 Total impact

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    ABSTRACT: Background:Previous reports have shown potential disadvantages of limus-derivative drugs for the stenting treatment of patients with diabetes mellitus (DM).Methods and Results:We studied 159 coronary artery lesions (DM: n=72, non-DM: n=87) in 123 patients treated with everolimus-eluting stent (EES) and who underwent scheduled 9-month follow-up angiography with optical coherence tomography (OCT) regardless of symptoms. In addition to standard OCT variables, neointimal unevenness score (maximum/average neointimal thickness) and stent eccentricity index (minimum/maximum stent diameter) were calculated for each cross-section. To investigate a potential baseline difference between DM and non-DM lesions, pre- and post-interventional intravascular ultrasound (IVUS) images were also evaluated as an IVUS subgroup analysis. The average neointimal thickness and neointimal coverage did not differ between DM and non-DM patients. DM patients had, however, greater asymmetric stent expansion and variability of neointimal thickness than non-DM patients. There was a weak, but significant association between average stent eccentricity index and neointimal unevenness score. The IVUS substudy showed that the culprit plaque volume and plaque eccentricity in DM patients were significantly greater than in non-DM patients.Conclusions:Although EES provided a similar level of average neointimal thickness and coverage both in the presence and absence of DM, uneven neointimal suppression occurred in DM patients. A larger plaque volume of the culprit lesion may hamper symmetric stent expansion, possibly explaining the non-uniform neointimal suppression in DM patients.
    Circulation journal : official journal of the Japanese Circulation Society. 07/2014;
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    ABSTRACT: Background:Nobori is a novel biolimus A9-eluting stent (BES) coated with a biodegradable polymer only on the abluminal side, which degrades over 6-9 months post-stent deployment. The course of vessel reaction after deployment at these time points remains unclear.Methods and Results:We serially evaluated 28 BES implanted in de novo coronary lesions of 23 patients using optical coherence tomography (OCT) at 6 and 12 months post-stenting. Standard OCT variables, the percentage of stent with peri-strut low-intensity area (PLIA, a region around stent struts homogenously showing lesser intensity than the surrounding tissue, suggesting fibrin deposition or impaired neointima maturation) and that with in-stent thrombi were evaluated. There was a significant, but small increase in neointimal thickness (72±23 to 82±25 µm, P=0.006) from the 6- to the 12-month follow-up, without a significant decrease in minimum lumen area (P=0.30). The incidences of uncovered and malapposed struts were low at 6 months and reduced further at 12 months (3.96±3.97% to 1.51±1.63%, P=0.001, and 0.50±1.84% to 0.06±0.24%, P=0.20, respectively). The frequency of stent with PLIA decreased during the follow-up (57% to 32%, P=0.05) and that with in-stent thrombi also numerically decreased (7% to 0%, P=0.24).Conclusions:Neointimal hyperplasia was persistently suppressed following BES implantation up to 12 months. Simultaneously, favorable vessel healing was achieved at 6 months without a delaying adverse reaction for up to 12 months.
    Circulation journal : official journal of the Japanese Circulation Society. 06/2014;
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    ABSTRACT: The consequences of acute strut malapposition in everolimus-eluting stents (EES) are unknown. This study investigated the impact of strut-vessel (S-V) distance and plaque type underneath acute strut malapposition on the mid-term vessel response in EES. Twenty-nine patients (35 EES) underwent optical coherence tomography (OCT) immediately after percutaneous coronary intervention and at 8-month follow-up. S-V distance and plaque type (lipid, calcified, or fibrous) underneath acute strut malapposition were evaluated. Follow-up OCT classified acute strut malapposition as persistent or resolved. The S-V cutoff value for predicting resolved strut malapposition and the incidence of intra-stent thrombi were determined. Among 569 cases of acute strut malapposition, involving 29,168 struts, 139 (24.4 %) were persistent. Mean S-V distance was significantly longer in persistent than in resolved strut malapposition (600 ± 294 vs. 231 ± 95 μm; P < 0.0001). S-V distance ≤380 μm was the best cutoff value for predicting resolved strut malapposition (sensitivity 93.5 %, specificity 69.8 %, area under curve 0.878). Acute strut malapposition with S-V distance ≤380 μm remained persistent more frequently over lipid/calcified than over fibrous plaques (lipid: 13.4 %, calcified: 18.2 %, fibrous: 4.2 %; lipid vs. fibrous, P = 0.001; calcified vs. fibrous, P = 0.02). Intra-stent thrombi were more frequent in stents with ≥1 persistent strut malapposition than in those without [4/11 stents (36.3 %) vs. 0/24 (0 %); P = 0.006]. Lipid and calcified plaque, together with S-V distance, affect the resolution of acute strut malapposition in EES. Persistent strut malapposition is associated with the presence of thrombi at follow-up, which could be the substrate for late stent thrombosis.
    The international journal of cardiovascular imaging 04/2014; · 2.15 Impact Factor
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    ABSTRACT: Background Although drug-eluting stents have significantly reduced the mid-term incidence of target lesion revascularization, however, in vivo studies on long-term vessel healing of sirolimus-eluting and paclitaxel-eluting stents (SES and PES) are limited. So the aim of this study was to compare long-term arterial healing in SES and PES. Methods We evaluated 27 SES (23 patients) and 21 PES (20 patients) by serial optical coherence tomography (OCT) at 6 months (mid-phase) and ≥3 years (late-phase) after stenting and evaluated the change of neointimal thickness (NIT), the percentages of uncovered and malapposed struts, peri-strut low intensity area (region around stent struts homogenously lower-intensity appearance than surrounding tissue), thrombus, and atherogenic neointima. Results At the follow-up, most SES showed a progressive increase in the average NIT, while PES showed variable changes. Between mid-phase and late-phase, NIT increased significantly in SES (mid-phase: 94.1 ± 49.3, late-phase: 130.2 ± 78.7; P = 0.001), but decreased significantly in PES (mid-phase: 167.4 ± 122.9, late-phase: 136.0 ± 77.7; P = 0.04). The percentages of uncovered struts decreased significantly in SES, on the other hand, variable changes were observed in PES. Peri-strut low intensity area and thrombus formation decreased in SES, but largely remained unchanged in PES. The prevalence of atherogenic neointima was greater in the late-phase than the mid-phase in both groups, but similar for both the stents. Conclusions Long-term vessel healing were different for SES and PES. Progressive vessel healing was consistently observed in SES, whereas a heterogeneous process of delayed vessel healing was noted for PES.
    The Canadian journal of cardiology 01/2014; · 3.12 Impact Factor
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    ABSTRACT: Background The addition of highly purified eicosapentaenoic acid (EPA) to statin therapy prevents cardiovascular events. However, the impact of this treatment on vulnerable plaques remains unclear. The aim of this study was to assess the impact of adding EPA to a standard statin therapy on vulnerable plaques by serial optical coherence tomography (OCT). Methods Forty-nine non-culprit thin-cap fibroatheroma (TCFA) lesions in 30 patients with untreated dyslipidemia were included. Patients were randomly assigned to EPA (1800 mg/day) + statin (23 TCFA, 15 patients) or statin only (26 TCFA, 15 patients) treatment. The statin (rosuvastatin) dose was adjusted to achieve a target low-density lipoprotein (LDL) level of <70 mg/dL. Post-percutaneous intervention and 9-month follow-up OCT were performed to evaluate morphological changes of TCFAs. The EPA/arachidonic acid (EPA/AA) ratio and pentraxin-3 (PTX3) levels were also evaluated. Results Despite similar follow-up LDL levels, the EPA + statin group had higher EPA/AA ratios and lower PTX3 levels than the statin group. OCT analysis showed that the EPA + statin group had a greater increase in fibrous-cap thickness, with a greater decrease in lipid arc and lipid length. Macrophage accumulation was less frequently detected in the EPA + statin group than in the statin group at follow-up. When the patients were categorized according to their follow-up PTX3 tertiles, fibrous-cap thickness showed significant increase, and the incidence of macrophages accumulation decreased with lower PTX3 levels. Conclusion The concomitant use of EPA and rosuvastatin may stabilize vulnerable plaques better than the statin alone, possibly by suppressing arterial inflammation.
    Atherosclerosis 01/2014; 234(1):114–119. · 3.71 Impact Factor
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    ABSTRACT: Background Previous reports have suggested the importance of delayed arterial healing and the development of neoatherosclerosis as major contributors to stent thrombosis and delayed restenosis. The difference of in vivo assessment of long-term vessel healing between first-generation drug-eluting stents and current generation everolimus-eluting stents (EESs) is limited. The aim of this study was to evaluate long-term arterial healing in EES in comparison with the first generation sirolimus-eluting stents (SES). Methods We evaluated 31 EES (23 patients) and 8 SES (7 patients) by serial optical coherence tomography at 12 months (mid-phase) and 24 months (late-phase) after stenting and evaluated the change in neointimal thickness (NIT), the percentages of uncovered struts, peri-strut low intensity area (PLIA; region around stent struts homogenously lower-intensity appearance than surrounding tissue), and thrombus. Results Although the average NIT showed no significant changes from the mid- to the late-phase follow-up in both EES and SES groups, the change in NIT and minimum lumen area was significantly larger in SES than EES (5.2 ± 29.4 vs. 37.2 ± 48.9; p = 0.02, −0.06 ± 0.36 vs. −0.45 ± 0.74; p = 0.04, respectively). The incidence of uncovered struts and struts with PLIA of EES was lower than those of SES, at both phases. Stents with in-stent thrombus of EES tended to be lower than that of SES at both phase follow-ups. Conclusion Although both SES and EES showed progressive luminal narrowing from the mid- to the late-phase follow-up, the extent of delayed lumen narrowing and delayed neointimal proliferation was significantly less in the second generation EES than the first generation SES. EESs seem to offer sustained stability in efficacy, without sacrificing safety, up to 2 years after implantation.
    Journal of Cardiology. 01/2014;
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    ABSTRACT: Although hemodialysis (HD) is a suggested risk factor for stent thrombosis, its contribution to local vessel healing after drug-eluting stent (DES) implantation is unclear. A total of 121 patients (152 lesions treated with DES) who underwent 8-month follow-up coronary angiography with optical coherence tomography (OCT) were enrolled, and the findings were compared between patients with and without HD. To match baseline differences, mid-term OCT findings of 42 propensity score-matched lesions (21 non-HD vs. 21 HD) were compared. Effects of HD on the efficacy of antiplatelet therapy were also evaluated by VerifyNow assay (Accumetrics, San Diego, CA, USA). Patients with HD had a significantly higher rate of thrombus formation than those without (64% vs. 33%, p=0.007), although the baseline parameters and lesion characteristics differed between the groups. Multivariate logistic regression analysis revealed that HD was associated with an increased risk of thrombus formation (odds ratio 5.991, 95% confidence interval: 1.972-18.199, p=0.002). Even after propensity-matching for patient background and balancing of angiographic and OCT variables, the risk of thrombus formation remained significantly higher in HD patients. The P2Y12-reaction unit was significantly increased after HD (Pre HD: 211±75 vs. Post HD: 262±59, p=0.01), but patients without HD showed no increase during the same elapsed time (221±88 vs. 212±96, p=0.19). HD is a potential risk factor for subclinical thrombus attachment after DES therapy. Systemic problems, such as residual platelet reactivity, associated with HD as well as local vessel features in HD patients might contribute to the increased incidence of thrombus attachment and subsequent onset of thrombotic event after DES implantation.
    Journal of Cardiology 12/2013; · 2.30 Impact Factor
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    ABSTRACT: Background: Although both optical coherence tomography (OCT) and angioscopy are robust tools for detecting intrastent thrombi and neoatherosclerosis in vivo, whether OCT findings are comparable with angioscopy findings remains unclear. Methods and Results: 22 patients presenting with de novo lesions underwent 26 sirolimus-eluting stent (SES) implantations, with follow-up OCT and angioscopy at 10 months post-implantation for segmental assessment of the proximal, mid-, and distal SES segments (66 segments). The mean signal intensity index (signal intensity of the neointima/signal intensity of fibrous intimal hyperplasia) was quantified for angioscopically detected in-stent yellow and white segments. The detection rate for red thrombi was numerically higher with angioscopy than with OCT (17% vs. 9%; P=0.053). Angioscopically detected in-stent yellow segments were categorized into 3 OCT patterns: "high-attenuation tissue covering struts" (OCT-defined neoatherosclerosis), "high-attenuation tissue underneath struts," and "low-attenuation and low-intensity tissue covering struts"; further, macrophage-like appearance was most frequently observed with OCT-defined neoatherosclerosis (56%, 6.3%, and 0%, respectively, P<0.001). The mean signal intensity index of neoatherosclerosis was significantly lower than that of angioscopically detected in-stent white segments (0.929 vs. 0.997, P=0.004). Conclusions: Current OCT-based definitions for thrombus detection may underestimate the presence of subclinical red thrombi. Qualitative and quantitative OCT assessments of the neointima may enhance the detection of neoatherosclerosis over SES in vivo.
    Circulation Journal 10/2013; · 3.58 Impact Factor
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    ABSTRACT: The impact of paraoxonase-1 (PON1) activity on the response to clopidogrel may differ in patients treated with drug-eluting stents (DES) in association with CYP2C19 loss-of-function (LOF) polymorphisms. This study included 112 Japanese patients receiving clopidogrel (75mg/day) and aspirin (100mg/day) who underwent optical coherence tomography (OCT) examination 9months after DES implantation. The CYP2C19 genotype was analyzed and LOF carriers (*1/*2, *1/*3, *2/*2, *3/*3, *2/*3) were identified. At the 9-month follow-up, platelet reactivity was determined by measuring the P2Y12 reactivity unit (PRU) using a VerifyNow P2Y12 assay, PON1 activity was evaluated and intra-stent thrombus was evaluated by OCT. Of the 112 Japanese patients, 75 were LOF carriers (67.0%). The patients were divided into tertiles according to the PON1 activity (tertile 1; <230U/L, tertile 2; 230-283U/L, tertile 3; >283U/L). In the VerifyNowP2Y12 analysis, tertile 1 had a higher PRU than tertiles 2 and 3 in LOF carriers, and there was no difference among tertiles in non-carriers. The highest incidence of intra-stent thrombus was observed in tertile 1 followed by tertiles 2 and 3 in LOF carriers, whereas there was no such difference in non-carriers. Multivariate analysis revealed that LOF carriers and PON1 activity tertile 1 were independent predictors of intra-stent thrombus in all patients. In LOF carriers, tertile 1 was the only independent predictor for intra-stent thrombus. Low PON1 activity is associated with a low response to clopidogrel and a high frequency of intra-stent thrombus only in LOF carriers.
    Thrombosis Research 09/2013; · 3.13 Impact Factor
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    ABSTRACT: Background: Treatment of coronary bifurcation lesions using a single stenting strategy is preferable over that using a 2-stent technique. The benefit of final kissing inflation (FKI), however, has not been established. Methods and Results: Seventy-two patients (76 lesions) with true bifurcation lesions treated with a single drug-eluting stent with FKI (n=33 lesions) or without FKI (non-FKI, n=43 lesions) were enrolled in this study. Optical coherence tomography (OCT) was performed at 6-12 months after implantation. Based on the OCT findings, the percentage of jailing struts (number of jailing struts/total number of struts at the bifurcation lesion) was calculated. Percentage of uncovered struts and frequency of thrombus attachment were each evaluated at the proximal, bifurcation, and distal segments. Major adverse cardiac events (MACE) were also evaluated. The percentage of jailing struts was significantly lower in the FKI than in the non-FKI group (5.8±6.2% vs. 17.3±6.1%, P<0.01). Thrombus attachment was less frequent in the FKI group (24.2% vs. 46.5%, P=0.046), especially at side-branch orifices (3.0% vs. 27.9%, P<0.001). The percentage of uncovered struts was lower in the FKI than non-FKI group at the proximal, bifurcation, and distal segments. The incidence of MACE was not different in this small cohort. Conclusions: FKI might reduce the frequency of subclinical thrombus possibly by reducing the number of jailing struts.
    Circulation Journal 02/2013; · 3.58 Impact Factor
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    ABSTRACT: A 65-year-old man was referred to our hospital due to an acute onset of dyspnea and persistent fever. Echocardiography revealed an ejection fraction (EF) of 25% with diffuse severe left ventricular (LV) dysfunction. 18F-fluorodeoxy glucose-positron emission tomography imaging showed significantly increased uptake by the LV and right ventricular walls, indicating active inflammation. The histologic findings of the endomyocardial biopsy specimens indicated the presence of epithelioid cell granuloma. The final diagnosis was thus cardiac sarcoidosis with acute inflammation. Five-months after the initiation of steroid therapy, echocardiography showed an EF of 50%. This is a rare case in which acute inflammation led to acute heart failure mimicking acute myocarditis.
    Internal Medicine 01/2013; 52(1):71-4. · 0.97 Impact Factor
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    ABSTRACT: Background: We hypothesized that the tissue components of in-stent restenosis (ISR) might differ between drug-eluting stents (DES) and bare-metal stents (BMS) and that these differences could be distinguished by qualitative and quantitative optical coherence tomography (OCT) analyses. Methods and Results: One-hundred and twenty-two initial ISR lesions (sirolimus-eluting stents: n=28; paclitaxel-eluting stents: n=51; BMS: n=43) were evaluated with OCT. Based on their OCT appearance, the lesions were classified as homogeneous, layered or heterogeneous. The optical properties of backscatter, attenuation and signal intensity of the neointimal tissue (NIT) were quantified. To evaluate the vascular response after balloon angioplasty (BA), the rate of reduction of the NIT area (NITA) was calculated (NITA before - after BA/NITA before BA at the minimum lumen cross-sectional area). Among the morphologic OCT patterns, the layered type was predominant with DES, whereas lesions were homogeneous with BMS (P<0.001). Backscatter and signal intensity were significantly higher with BMS (P<0.05 and P<0.001 respectively). The NITA reduction rate was significantly greater in the layered and heterogeneous groups than in the homogeneous group (P<0.01). Conclusions: The morphologic OCT patterns of the NIT in ISR differed significantly between DES and BMS, probably reflecting pathologic differences. Layered and heterogeneous tissues might respond better than homogeneous tissue to simple balloon dilatation, suggesting a possible direction for OCT-based ISR treatment strategies.
    Circulation Journal 12/2012; · 3.58 Impact Factor
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    ABSTRACT: Background: Cytochrome P450 (CYP) 2C19 polymorphism is associated with reduced responsiveness to clopidogrel and poor clinical outcome after drug-eluting stent (DES) implantation, but its contribution to lesion outcome after DES implantation is unclear. Methods and Results: The study included 160 Japanese patients who received clopidogrel and underwent DES implantation with follow-up angiography. Patients were divided into 3 groups by CYP2C19 polymorphism: extensive metabolizers (EM), intermediate metabolizers (IM), and poor metabolizers (PM). The incidence of major adverse cardiac events (MACE) and target lesion revascularization (TLR) were compared among the 3 groups. Optical coherence tomography (OCT) was performed for 120 patients to evaluate the incidence of intra-stent thrombi. Of the 160 patients, the proportion of EM, IM, and PM was 37.5%, 48.1%, and 14.4%, respectively. The incidence of TLR and MACE was more frequent in IM and PM than EM (TLR: 18.2% and 26.1% vs. 3.3%, P=0.008, MACE: 22.1% and 30.4% vs. 5.0%, P=0.005). Among the 120 patients who underwent follow-up OCT, intra-stent thrombi were more frequently detected in IM and PM than in EM (45.6% and 63.2% vs. 20.5%, P=0.005). The incidence of TLR was significantly higher in patients with than in those without intra-stent thrombi (27.7% vs. 6.8%, P=0.003). Conclusions: CYP2C19 loss-of-function polymorphism might be associated with the incidence of MACE and TLR in association with intra-stent thrombi.  (Circ J 2012; 76: 2348-2355).
    Circulation Journal 07/2012; 76(10):2348-55. · 3.58 Impact Factor
  • Journal of the American College of Cardiology 61(10):E64. · 14.09 Impact Factor