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Yasuhiro Honda

Publications and source records attributed to Yasuhiro Honda.

At least 19 recordsLinked to original sources

Comparison of the efficacy of direct coronary stenting with sirolimus-eluting stents versus stenting with predilation by intravascular ultrasound imaging (from the DIRECT trial).

A direct coronary stenting technique using drug-eluting stents may decrease drug-eluting stent efficacy due to possible damage to the surface coating of the stent. The DIRECT is a multicenter, prospective, nonrandomized trial designed to evaluate the direct stenting strategy for the sirolimus-eluting Bx-Velocity stent compared with the historical control (SIRIUS trial, stenting with predilation). Volumetric and cross-sectional intravascular ultrasound analyses at 8-month follow-up were performed in 115 patients (DIRECT n= 64, control n = 51). Patient and lesion characteristics were comparable between groups. The DIRECT group achieved an equivalent uniform expansion index, defined as minimum stent area/maximum stent area x 100, compared with the control group (65.9 +/- 11.7 vs 63.1 +/- 12.7, p = NS). At 8-month follow-up, vessel, stent, lumen, and neointimal volume index (volume in cubic millimeters/length in millimeters) and percent neointimal volume were similar between the DIRECT and control groups (vessel volume index 13.9 +/- 4.40 vs 15.0 +/- 3.83; stent volume index 6.83 +/- 2.02 vs 6.94 +/- 2.04; lumen volume index 6.71 +/- 2.04 vs 6.81 +/- 2.07; neointimal volume index 0.14 +/- 0.24 vs 0.16 +/- 0.23; percent neointimal volume 3.73 +/- 6.97 vs 3.14 +/- 5.32, p = NS for all). In addition, in-stent neointimal hyperplasia distribution was significantly smaller near the distal stent edge (0.22 vs 0.098 mm(3)/mm, p = 0.01 for an average neointimal volume index within 3 mm from the distal stent edge). In conclusion, direct coronary stenting with the sirolimus-eluting Bx-Velocity stent is equally effective in terms of uniform stent expansion and long-term quantitative intravascular ultrasound results compared with conventional stenting using predilation. This strategy appears to be associated with less neointimal hyperplasia near the distal stent edge.

Coronary Stenosis↗

Intravascular ultrasonic analysis of atherosclerotic vessel remodeling and plaque distribution of stenotic left anterior descending coronary arterial bifurcation lesions upstream and downstream of the side branch.

Bifurcation lesions remain a challenging lesion subset, even in the era of drug-eluting stents. The aim of this study was to investigate the longitudinal remodeling pattern and cross-sectional plaque location of bifurcation lesions. Seventy-four preintervention intravascular ultrasound studies of left anterior descending bifurcation lesions were analyzed, in which the lesion was located proximal (type A, n=32) or distal (type B, n=42) to the side branch. Vessel area and plaque area at the lesion (VAlesion and PAlesion) and at the reference site (VAreference and PAreference) were measured. The remodeling ratio was defined as VAlesion/VAreference, and the vessel compensation ratio was defined as (VAlesion-VAreference)/(PAlesion-PAreference). The geometric center of the lumen at the lesion site was identified, and the lesion site was divided into circumferential equal arcs to compare the cross-sectional distribution of percentage plaque area (100x[PAlesion/VAlesion]) between the 2 groups. The remodeling ratio (1.03+/-0.15 vs 0.94+/-0.14, p=0.01) and the vessel compensation ratio (0.0+/-0.36 vs -0.37+/-0.61, p<0.01) were significantly greater in type A than in type B lesions. The circumferential distribution pattern of percentage plaque area was significantly different between the groups (analysis of variance p<0.005), with greater percentage plaque area for the vessel wall opposite from the side branch in type B lesions (46.3+/-18.0% vs 54.6+/-15.4%, type A vs type B lesions, p<0.05). In conclusion, these results suggest that a major side branch may affect longitudinal lesion remodeling as well as the circumferential location of atherosclerotic plaque.

Coronary Artery Disease↗

Influence of plaque calcium on neointimal hyperplasia following bare metal and drug-eluting stent implantation.

OBJECTIVES: To examine the influence of vessel wall calcium on neointimal hyperplasia (NIH) following bare metal stent (BMS) and drug-eluting stent (DES) implantation. BACKGROUND: While procedural complications with coronary stenting in calcified lesions are well reported, little is known about subsequent NIH on plaque calcium following either BMS or DES implantation. METHODS: In the Study to COmpare REstenosis Rate between QueST and QuaDDS-QP2 (SCORE) trial, 6 months follow-up volumetric intravascular ultrasound data were available for 41 lesions (BMS, 19; DES, 22). NIH thicknesses on superficial, deep, and noncalcified plaque were calculated at every 0.5 mm intervals over the stented segment. Calcified and less-calcified cross-sections were defined as those containing arcs of plaque calcium > or = 90 degrees and < 90 degrees , respectively. RESULTS: In BMS, mean NIH thickness on both superficial (0.24 +/- 0.23 mm) and deep calcium (0.25 +/- 0.21 mm) was significantly smaller than that of noncalcified plaque (0.31 +/- 0.22 mm) (P < 0.0005). NIH area was significantly smaller in calcified cross-sections compared to less-calcified cross-sections (2.1 +/- 1.2 mm2 vs. 3.1 +/- 1.9 mm2, P < 0.0001). While in contrast, in DES, mean NIH thickness was similar, irrespective of the presence or location of calcium (0.03 +/- 0.05 mm vs. 0.03 +/- 0.06 mm vs. 0.03 +/- 0.05 mm, superficial vs. deep vs. noncalcified plaque, P = NS). NIH area was also similar between calcified and less-calcified cross-sections (0.3 +/- 0.6 mm2 vs. 0.3 +/- 0.6 mm2, P = NS). CONCLUSIONS: These results suggest that while plaque calcium may influence NIH following BMS implantation, NIH suppression using DES does not appear to be affected by the presence or location of calcium.

Bridged-Ring Compounds↗

Mechanisms of lumen narrowing of saphenous vein bypass grafts 12 months after implantation: an intravascular ultrasound study.

BACKGROUND: Previous long-term (>1 year) studies have suggested that saphenous vein bypass grafts (SVGs) undergo vascular remodeling similar to native coronary arteries. However, early morphologic stages of SVG remodeling have not been characterized in vivo. METHODS: Thirty SVGs were studied 12 months after implantation using an intravascular ultrasound automated pullback system. Intravascular ultrasound images were analyzed between 10 and 60 mm from the tip of the guide. Lumen area (LA), intima area (IA), and vessel area (VA, defined as the area within the outer border of a hypoechoic intimal layer) were computed at 3 cross sections: the minimum LA (MLA) site and the proximal and distal reference sites. Area changes (Delta) were calculated as the MLA site minus the average of the reference sites. RESULTS: In this cohort, 70% of the MLA sites had a smaller VA than the average references. On average, MLA sites had significantly smaller VA (9.7 +/- 2.9 vs 10.7 +/- 3.2 mm2, P < .01) and larger IA (2.5 +/- 2.1 vs 1.2 +/- 1.3 mm2, P < .01) than at the reference sites. The relative contribution of DeltaVA (-1.0 +/- 1.4 mm2) and DeltaIA (1.3 +/- 1.3 mm2) to lumen compromise (-2.3 +/- 1.4 mm2) were 43% and 57%, respectively. On the other hand, simple linear regression analysis revealed a significant positive correlation between DeltaIA and DeltaVA (y = -1.7 + 0.52x, r = 0.50, P < .01). CONCLUSIONS: Within the first year, the mechanism of lumen compromise in SVG is a combination of negative remodeling and intimal hyperplasia. Positive remodeling is seen in a minority of cases. However, the direction and extent of remodeling correlated with change in intimal thickness.

Aged↗

Transient left ventricular dysfunction under severe stress: brain-heart relationship revisited.

PURPOSE: Transient left ventricular dysfunction in patients under emotional or physical stress, also known as tako-tsubo-like left ventricular dysfunction, has been recently been recognized as a distinct clinical entity. The aims of this review are to define this phenomenon and to explore its similarities to the left ventricular dysfunction seen in patients with acute brain injury. METHODS: MEDLINE database, bibliographies of each citation for relevant articles, and consultation with clinical experts were used to examine the clinical picture of tako-tsubo-like left ventricular dysfunction. RESULTS: We identified case series and a systematic review that report on patients with this syndrome. This phenomenon occurs predominantly in female patients, presenting with a variety of ST-T segment changes and mildly elevated cardiac enzymes that mimic an acute coronary syndrome. The left ventricular dysfunction, typically showing a hyperkinetic basal region and an akinetic apical half of the ventricle, occurs in the absence of obstructed epicardial coronary arteries. The ventricular dysfunction usually resolves within weeks with a generally favorable prognosis. This phenomenon has similarities to that seen in patients with acute brain injury with regard to clinical presentation, pathology, and its reversible nature. CONCLUSIONS: Transient left ventricular dysfunction occurs in the absence of obstructive epicardial coronary artery disease. In its broadest sense, this phenomenon may encompass a range of disorders including left ventricular dysfunction after central nervous system injury.

Electrocardiography↗

Predictors of recurrent in-stent restenosis after beta-radiation: An analysis from the START 40/20 trial.

OBJECTIVE: The purpose of this study was to identify potential predictors, including clinical, procedural, angiographic, and intravascular ultrasound (IVUS) parameters, for recurrent in-stent restenosis (ISR) following beta-radiation 90Strontium/Yttrium (90Sr/Y) in a large multicenter trial. BACKGROUND: Although adjunct brachytherapy reduces recurrent ISR after primary catheter-based intervention, recurrence of stenosis after brachytherapy still occurs. METHODS: We analyzed 185 IVUS cohort patients in the STent And Restenosis Therapy (START) 40/20 trial where a 40-mm, 90Sr/Y, radioactive source train was exclusively used for treatment of ISR to be treatable with a 20-mm balloon. RESULTS: Thirty-nine patients underwent target lesion revascularization. Preliminary univariate analysis showed that age, smoking, balloon/artery ratio, geographic miss, minimum lumen diameter, and diameter stenosis at baseline were associated with target lesion revascularization, while none of IVUS variables were (minimum lumen area, minimum stent area, or residual plaque burden). The multivariate logistic regression analysis showed that younger age, lower balloon/artery ratio, and presence of geographic miss were independent predictors of target lesion revascularization. CONCLUSIONS: Even with adjunct beta-radiation therapy, initial mechanical optimization, such as appropriate balloon sizing and positioning, may be critical for the prevention of recurrent ISR.

Adult↗

Safety of beta radiation exposure to the non-target segment: an intravascular ultrasound dosimetric analysis.

BACKGROUND: The use of longer radioactive seed trains to avoid geographic miss may lead to greater radiation exposure to distal vasculature due to the natural tapering of coronary arteries. The aim of this study was to use IVUS-based dosimetric analysis to evaluate the effect of beta-radiation on angiographically normal, noninjured distal segments. METHODS: We analyzed 17 in-stent restenosis cases (stent length: 20 +/- 8 mm) treated with a 40 mm 90Sr/Y source train. The prescribed dose was 18.4 Gy (reference less than or equal to 3.3 mm) or 23 Gy (reference > 3.3 mm) at 2 mm from the source. Noninjured, but fully radiated, distal reference sites were determined by angiography. Based upon the three-dimensional vessel contours obtained at baseline, the minimum dose delivered to 90% of plaque volume (Dv90) was determined. Vessel, plaque and lumen volumes and Dv90 were computed in every 2 mm subsegment (n = 52). RESULTS: On average, no significant serial change was observed in plaque area (5.0 +/- 2.5 mm3/mm post-treatment to 5.6 +/- 3.1 mm3/mm at 8-month follow up; p = 0.09), vessel area (10.2 +/- 3.7 to 10.3 +/- 4.0 mm3/mm; p = 0.84), or lumen area (5.2 +/- 2.0 to 4.7 +/- 1.8 mm3/mm; p = 0.19). Subsegment analysis, however, revealed a wide range of dose distribution, with a significant positive correlation between Dv90 and plaque increase (p = 0.008), as well as vessel change (p < 0.001), representing dose-dependent positive vessel remodeling following beta radiation. Consequently, no significant relationship was observed between Dv90 and lumen change. CONCLUSIONS: Detailed IVUS-based dosimetric analysis demonstrated that beta radiation promoted positive remodeling, preventing lumen loss despite a mild increase in plaque mass on angiographically normal, noninjured distal segments.

Aged↗

Axial plaque redistribution after coronary stent deployment.

We report a case of axial plaque redistribution after coronary stent deployment assessed by intravascular ultrasound (IVUS) as well as coronary angiography. A 72-year-old male with a history of hypertension, hyperlipidemia and a nuclear stress test demonstrating anterior and lateral ischemia was admitted for cardiac catheterization. Coronary angiography and IVUS examination revealed eccentric stenoses in the left anterior descending artery (LAD) and the left circumflex artery (LCx), just before the bifurcation of the first obtuse marginal branch. After successful LAD stent placement, the LCx was also stented, jailing the obtuse marginal branch. Immediately after dilatation, however, the coronary angiogram showed a new significant stenosis at the distal adjacent segment. IVUS examination after administration of nitroglycerin revealed a secondary critical lesion that was not observed before the interventional procedure. A significant plaque increase at the new lesion site presumably resulted from axial plaque redistribution (extrusion from the stented segment, otherwise known as plaque shift). After additional stenting, the patient had an uneventful course.

Aged↗

Heterogeneity of neointimal distribution of in-stent restenosis in patients with diabetes mellitus.

Diabetes mellitus is an independent predictor of restenosis after percutaneous coronary intervention. The pattern of restenosis after bare metal stent implantation in diabetic patients was examined with 3-dimensional intravascular ultrasound analysis. Lumen and stent were manually traced at every 0.5-mm interval in stented segments. Using Simpson's method, stent, luminal, and neointimal (stent minus lumen) volumes were calculated and average area was calculated as volume data divided by length. To measure the cross-sectional and longitudinal severities of luminal encroachment by the neointima, percent neointimal area (neointimal area divided by stent area) and neointimal hyperplasia 50 (IH50) (defined as percent stent length with percent neointimal area >50%) were calculated. In 278 patients (68 with diabetes and 210 without diabetes), there was a significantly higher percentage of maximal percent neointimal area with significantly longer percent stent length that was severely encroached by the neointima in diabetic patients. Diabetic patients showed a more heterogenous pattern of the neointima after bare metal stenting, resulting in longer high-grade obstruction segments. This may have important implications for stent design and pharmacokinetic properties of next-generation drug-eluting technology for this complex patient subset.

Aged↗

Impact of asymmetric stent expansion on neointimal hyperplasia following sirolimus-eluting stent implantation.

To assess whether asymmetric stent expansion affects suppression of neointimal hyperplasia after sirolimus-eluting stent implantation, 64 patients in the SIRolImUS-coated Bx Velocity stent trial who underwent single 18-mm stent implantation and 3-dimensional intravascular ultrasonography at 8-month follow-up were enrolled. To assess the longitudinal stent asymmetric expansion, 2 cross sections with a maximal/minimal stent area were chosen in each patient. To assess for tomographic stent asymmetric expansion, stent eccentricity was determined by dividing the minimum stent diameter by the maximum stent diameter. At the 2 cross sections with a maximal/minimal stent area, a sirolimus-eluting stent reduced neointimal hyperplasia significantly with no interaction between the treatment and stent areas. A sirolimus-eluting stent also significantly reduced neointimal hyperplasia in the concentric and eccentric stent groups.

Angioplasty, Balloon, Coronary↗

Late incomplete stent apposition after sirolimus-eluting stent implantation: a serial intravascular ultrasound analysis.

OBJECTIVES: We sought to identify the frequency of incomplete stent apposition (ISA) in sirolimus-eluting stents (SES) and clarify its findings and clinical sequelae. BACKGROUND: Late-acquired ISA has been reported in bare-metal stents (BMS) and brachytherapy and recently in drug-eluting stents. However, the characteristics of late ISA in SES have not been clarified. METHODS: From the SIRIUS trial, a randomized, multicenter study comparing SES and BMS, serial qualitative intravascular ultrasound (IVUS; at stent implantation and eight-month follow-up) was available in 141 patients (BMS: n = 61; SES: n = 80). The IVUS images were reviewed for the presence of ISA. RESULTS: Incomplete stent apposition at follow-up was observed in 19 patients (BMS: n = 6 [9.8%]; SES: n = 13 [16.3%]; p = NS). Among these, 12 had ISA after intervention and at follow-up (persistent ISA). Late-acquired ISA was seen in the remaining seven cases, all from the SES group (BMS: n = 0; SES: n = 7 [8.7%]; p < 0.05). In late-acquired ISA, there was an increase in external elastic membrane area (after intervention: 16.2 +/- 2.7 m2; follow-up: 18.9 +/- 3.6 mm2; p < 0.05). The location of stent-vessel wall separation was primarily at the stent edges in persistent ISA cases, whereas late-acquired ISA in SES occurred mostly in the mid portion of the stent. There were no negative clinical events reported for any ISA cases at 12-month clinical follow-up. CONCLUSIONS: Late ISA was observed in 8.7% of patients after SES implantation. There were no negative clinical events associated with this IVUS finding at 12-month clinical follow-up; however, careful long-term follow-up will be necessary.

Combined Modality Therapy↗

Predictors of edge stenosis following sirolimus-eluting stent deployment (a quantitative intravascular ultrasound analysis from the SIRIUS trial).

To study the interaction of the sirolimus-eluting stent and vessel margins, we analyzed the intravascular ultrasound parameters in 317 edges of 167 stents having 18 edge stenoses at 8 months of follow-up from the SIRIUS trial. Of the baseline parameters, a larger reference percentage of plaque area and a larger edge stent area/reference minimum lumen area were associated with edge stenosis in the sirolimus-eluting stent cohort compared with the incidence of edge stenosis in the bare metal stent cohort. Thus, full lesion coverage and matching the stented segment properly to the adjacent segment using intravascular ultrasound guidance may improve sirolimus-eluting stent implantation efficacy further.

Blood Vessel Prosthesis Implantation↗

Impact of intravascular ultrasound lesion characteristics on neointimal hyperplasia following sirolimus-eluting stent implantation.

The effect of lesion characteristics on neointimal hyperplasia after sirolimus-eluting stent implantation was examined in 45 patients who underwent successful preinterventional intravascular ultrasound. There were no differences in neointimal hyperplasia between the moderate/severe calcified lesion group (calcium arc >120 degrees ) and the non/mild calcified lesion group or between the positive vessel remodeling group (external elastic membrane area at the minimal lumen area site larger than that at the proximal reference site) and negative vessel remodeling group. No correlation between preinterventional plaque burden and neointimal hyperplasia was found. In patients who have coronary artery disease, sirolimus-eluting stents continue to demonstrate striking suppression of neointimal proliferation, irrespective of lesion characteristics previously associated with greater restenotic risk.

Blood Vessel Prosthesis Implantation↗

Effect of lumen narrowing within coronary stents on proximal and distal vessel segments following bare metal stent implantation.

Adjacent reference vessel response to smaller lumens at stented segments was examined with 3-dimensional intravascular ultrasound analysis. In 128 patients after bare metal stent implantation, minimal lumen area (MLA) within the stent and average lumen area at distal/proximal adjacent reference segments (5 mm) were obtained at baseline and follow-up. In the smaller in-stent MLA group (MLA <3 mm2), lumen area decreased significantly at the distal edge compared with the larger in-stent MLA group (MLA > or =3 mm2), although no significant difference was seen at the proximal edge. In-stent lumen patency may influence vascular responses at adjacent reference segments after bare metal stent implantation.

Coronary Disease↗

Impact of different definitions on the interpretation of coronary remodeling determined by intravascular ultrasound.

The objective of this study was to compare the categorizations and determinants related to remodeling by the three definitions commonly used. Several morphological and intravascular ultrasound (IVUS) studies have demonstrated the fundamental importance of arterial remodeling in atherosclerosis. However, lack of consensus on how to define remodeling has led to conflicting analyses of factors that influence this process. Analysis of pre-interventional IVUS images of 514 lesions in native coronary arteries was performed. Arterial remodeling was defined as outward by definition 1, when [cross-sectional area (CSA) of the external elastic membrane (EEM) at the lesion site (EEM(lesion))]/[EEM CSA either at the proximal (EEM(prox ref)) or distal (EEM(distal ref)) reference site with the least amount of plaque] was > 1.05, intermediate when this ratio was between 0.95 and 1.05, and inward when < 0.95. Remodeling was defined as outward by definition 2 when EEM(lesion) > both EEM(prox ref) and EEM(distal ref), inward when EEM(lesion) < both EEM(prox ref) and EEM(distal ref), and intermediate when EEM(lesion) was intermediate between EEM(prox ref) and EEM(distal ref). By definition 3, vessel remodeling was defined as outward when EEM(lesion) > (EEM(prox ref) + EEM(distal ref))/2 and intermediate/inward when EEM(lesion) < or = (EEM(prox ref) + EEM(distal ref))/2. The frequency of outward remodeling was significantly higher by definitions 1 and 3 than by definition 2, whereas a higher frequency of inward remodeling was observed in definition 1, resulting in significantly different remodeling distributions between the three definitions (P < 0.0001). By multivariate logistic analysis, the only clinical determinants related to outward remodeling was younger age, and only by definition 3. IVUS determinants varied significantly between the three definitions. The only consistent determinants among the three definitions were smaller lumen CSA at the reference site and larger plaque + media CSA at the lesion site. This study demonstrates the significant impact of different remodeling definitions on the incidence and determinants of remodeling patterns. The marked variability in categorization of remodeling underscores the importance of developing a standard methodology.

Aged↗

Sclerotherapy for gastric fundal variceal bleeding: is complete obliteration possible without cyanoacrylate?

BACKGROUND: Many studies have suggested that endoscopic obliteration using cyanoacrylate for bleeding gastric fundal varices is effective. However, serious complications by injection of cyanoacrylate into varices have also been reported. METHODS: Thirty patients with bleeding gastric fundal varices underwent endoscopic injection sclerotherapy using 5% ethanolamine oleate under fluoroscopic guidance plus infusion of vasopressin and a transdermal nitroglycerin patch. The injection of 5% ethanolamine oleate was continued until it filled the varices and their feeder veins under fluoroscopic guidance. The injection needle was removed while thrombin glue was sprayed at the puncture site through the side hole of the injector needle to prevent bleeding from the puncture site. RESULTS: Complete hemostasis was achieved in 28/30 patients (93.3%). The cumulative rebleeding rate after 1, 3 and 5 years was 13%, 19% and 19%, respectively. The 1-, 3-, and 5-year cumulative mortality rates were 31%, 54% and 59%, respectively. There was no complication related to infusion of vasopressin and sclerotherapy procedure. CONCLUSION: The sclerotherapy method carried out using 5% ethanolamine oleate combined with infusion of vasopressin under fluoroscopic guidance might be a feasible method for obliteration of gastric fundal varices as an alternative to cyanoacrylate.

Adult↗

Impact of final stent dimensions on long-term results following sirolimus-eluting stent implantation: serial intravascular ultrasound analysis from the sirius trial.

OBJECTIVES: We assessed the predictive value of minimum stent area (MSA) for long-term patency of sirolimus-eluting stents (SES) implantation compared to bare metal stents (BMS). BACKGROUND: Although MSA is a consistent predictor of in-stent restenosis, its predictive value in BMS is still limited because of biologic variability in the restenosis process. METHODS: From the SIRolImUS (SIRIUS) trial, 122 cases (SES: 72; BMS: 50) with complete serial intravascular ultrasound (IVUS) (baseline and 8-month follow-up) were analyzed. Postprocedure MSA and follow-up minimum lumen area (MLA) were obtained. Based on previous physiologic studies, adequate stent patency at follow-up was defined as MLA >4 mm(2). RESULTS: In both groups, a significant positive correlation was observed between baseline MSA and follow-up MLA (SES: p < 0.0001, BMS: p < 0.0001). However, SES showed higher correlation than BMS (0.8 vs. 0.65) with a higher regression coefficient (0.92 vs. 0.59). The sensitivity and specificity curves identified different optimal thresholds of MSA to predict adequate follow-up MLA: 5 mm(2) for SES and 6.5 mm(2) for BMS. The positive predictive values with these cutoff points were 90% and 56%, respectively. CONCLUSIONS: In this SIRIUS IVUS substudy, SES reduced both biologic variability and restenosis, resulting in increased predictability of long-term stent patency with postprocedure MSA. In addition, SES had a considerably lower optimal MSA threshold compared to BMS.

Angioplasty, Balloon, Coronary↗