Dual Antiplatelet Therapy Duration After Multivessel Optimal Intravascular Ultrasound-Guided Percutaneous Coronary Intervention.

BACKGROUND: There is a scarcity of data evaluating contemporary real-world dual antiplatelet therapy (DAPT) strategies after percutaneous coronary intervention (PCI).Methods and Results: In the OPTIVUS-Complex PCI study multivessel cohort enrolling 982 patients undergoing multivessel PCI, including left anterior descending coronary artery using intravascular ultrasound (IVUS), we conducted 90-day landmark analyses to compare shorter and longer DAPT. DAPT discontinuation was defined as withdrawal of P2Y12inhibitors or aspirin for at least 2 months. The prevalence of acute coronary syndrome and high bleeding risk by the Bleeding Academic Research Consortium were 14.2% and 52.5%, respectively. The cumulative incidence of DAPT discontinuation was 22.6% at 90 days, and 68.8% at 1 year. In the 90-day landmark analyses, there were no differences in the incidences of a composite of death, myocardial infarction, stroke, or any coronary revascularization (5.9% vs. 9.2%, log-rank P=0.12; adjusted hazard ratio, 0.59; 95% confidence interval, 0.32-1.08; P=0.09) and BARC type 3 or 5 bleeding (1.4% vs. 1.9%, log-rank P=0.62) between the off- and on-DAPT groups at 90 days. CONCLUSIONS: The adoption of short DAPT duration was still low in this trial conducted after the release of the STOPDAPT-2 trial results. The 1-year incidence of cardiovascular events was not different between the shorter and longer DAPT groups, suggesting no apparent benefit of prolonged DAPT in reducing cardiovascular events even in patients who undergo multivessel PCI.

Comparison of the OPTIVUS-Complex PCI Multivessel Cohort With the Historical CREDO-Kyoto Registry Cohort-3.

BACKGROUND: There is a paucity of data on the effect of optimal intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) compared with standard PCI or coronary artery bypass grafting (CABG) in patients with multivessel disease.Methods and Results: The OPTIVUS-Complex PCI study multivessel cohort was a prospective multicenter single-arm study enrolling 1,021 patients undergoing multivessel PCI including the left anterior descending coronary artery using IVUS aiming to meet the prespecified criteria for optimal stent expansion. We conducted propensity score matching analyses between the OPTIVUS group and historical PCI or CABG control groups from the CREDO-Kyoto registry cohort-3 (1,565 and 899 patients) fulfilling the inclusion criteria for this study. The primary endpoint was a composite of death, myocardial infarction, stroke, or any coronary revascularization. In the propensity score-matched cohort (OPTIVUS vs. historical PCI control: 926 patients in each group; OPTIVUS vs. historical CABG control: 436 patients in each group), the cumulative 1-year incidence of the primary endpoint was significantly lower in the OPTIVUS group than in the historical PCI control group (10.4% vs. 23.3%; log-rank P<0.001) or the historical CABG control group (11.8% vs. 16.5%; log-rank P=0.02). CONCLUSIONS: IVUS-guided PCI targeting the OPTIVUS criteria combined with contemporary clinical practice was associated with superior clinical outcomes at 1 year compared with not only the historical PCI control, but also the historical CABG control.

Effects of sitagliptin on coronary atherosclerosis evaluated using integrated backscatter intravascular ultrasound in patients with type 2 diabetes: rationale and design of the TRUST study.

Patients with diabetes mellitus are at high risk for developing coronary artery disease (CAD), even if they are treated with statins. Several studies have shown the beneficial effects of dipeptidyl peptidase-4 (DPP-4) inhibitors on the cardiovascular system in an animal model. However, recent clinical trials using DPP-4 inhibitors have shown that these inhibitors fail to reduce the occurrence of cardiovascular events. Therefore, this study will be performed to evaluate the effects of sitagliptin, a DPP-4 inhibitor, on coronary atherosclerosis in patients with type 2 diabetes. This study will be a prospective, open-label, randomized multicenter trial performed in 6 centers in Japan. Stable CAD patients with type 2 diabetes who have undergone successful percutaneous coronary intervention under integrated backscatter (IB)-intravascular ultrasound (IVUS) guidance will be studied. They will be randomly assigned to either the sitagliptin group or a control group. After 48 weeks' treatment, the IVUS examination will be repeated in the same coronary artery as at baseline. The primary end point will be the percentage change in plaque volume measured using grayscale IVUS from baseline to the 48-week follow-up. This study will be the first multicenter trial to evaluate the effects of a DPP-4 inhibitor on coronary atherosclerosis evaluated using IB-IVUS, and the findings will clarify the anti-atherogenic effects of sitagliptin.

Optimal Intravascular Ultrasound-Guided Percutaneous Coronary Intervention in Patients With Multivessel Disease and Diabetes.

There is a scarcity of data on clinical outcomes after intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) in patients with multivessel disease and diabetes. The Optimal Intravascular Ultrasound Guided Complex Percutaneous Coronary Intervention study multivessel cohort was a prospective, multicenter, single-arm trial enrolling 1,021 patients who underwent multivessel PCI, including left anterior descending coronary artery using IVUS, aiming to meet the prespecified OPTIVUS criteria for optimal stent expansion. We compared the clinical outcomes between those patients with and without diabetes. The primary end point was a composite of death, myocardial infarction, stroke, or any coronary revascularization. There were 560 patients (54.8%) with diabetes and 461 patients (45.2%) without diabetes. The mean age was not different between the 2 groups (70.9 ± 9.7 vs 71.7 ± 10.4 years, p = 0.17). Patients with diabetes more often had chronic kidney disease and complex coronary artery disease, as indicated by the greater total number of stents and longer total stent length. The rate of meeting the OPTIVUS criteria was not different between the 2 groups (61.2% vs 60.7%, p = 0.83). The cumulative 1-year incidence of the primary end point was not different between the 2 groups (10.8% vs 9.8%, log-rank p = 0.65). After adjusting for confounders, the risk of diabetes relative to nondiabetes remained insignificant for the primary end point (hazard ratio 0.97, 95% confidence interval 0.65 to 1.44, p = 0.88). In conclusion, in patients who underwent multivessel IVUS-guided PCI and were managed with contemporary clinical practice, patients with diabetes had similar 1-year outcomes to patients without diabetes.

Validity and reliability of new intravascular ultrasound analysis software for morphological measurement of coronary artery disease.

BACKGROUND: Intravascular ultrasound (IVUS) analysis software enables precise planimetry measurement and tissue characterization of coronary plaque. Recently, a new IVUS analysis software compatible with integrated backscatter-IVUS, VISIATLAS(TM), was developed. The validity and reliability of VISIATLAS(TM) were evaluated. METHODS AND RESULTS: Forty patients who underwent IVUS-guided percutaneous coronary intervention were enrolled, and planimetry measurements were performed by 2 observers using VISIATLAS(TM) and echoPlaque(TM). IVUS analysis was performed in non-stent segments in 10 patients (non-target vessel, n=5; target vessel before stent implantation, n=5) at every 2.5mm for 20 slices in each patient. Stent segments were analyzed in the remaining 30 patients. With VISIATLAS(TM), the intraobserver and interobserver intraclass correlation coefficients (ICC) for the area of external elastic membrane (EEM), lumen, and plaque plus media (P+M) were 0.999 and 0.999, 0.996 and 0.993, and 0.993 and 0.991, respectively. The intersoftware ICC for EEM, lumen, and P+M area were 0.997, 0.993, and 0.985, respectively. The ICC of stent volume for intraobserver, interobserver and intersoftware comparisons were 0.997, 0.993, and 0.998, respectively. Bland-Altman plots showed small differences and narrow limits of agreement for all of the above parameters. CONCLUSIONS: VISIATLAS(TM) has high repeatability and reproducibility of measurement. This new IVUS analysis software is suitable for accurate measurement of coronary artery and stent structure in future IVUS studies.

Single-Session Versus Staged Multivessel Optimal IVUS-Guided PCI in Patients With CCS or NSTE-ACS.

Background: There are no studies comparing single-session vs staged multivessel intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) in patients with chronic coronary syndrome (CCS) or non-ST-segment-elevation acute coronary syndrome (NSTE-ACS). Objectives: The authors aimed to compare single-session vs staged multivessel IVUS-guided PCI in patients with CCS or NSTE-ACS. Methods: The OPTIVUS-Complex PCI study multivessel cohort was a prospective multicenter single-arm trial enrolling 1,021 patients with CCS or NSTE-ACS undergoing multivessel PCI including left anterior descending coronary artery using IVUS aiming to meet the prespecified OPTIVUS criteria for optimal stent expansion. We compared single-session vs staged multivessel PCI. The primary endpoint was a composite of death, myocardial infarction, stroke, or any coronary revascularization. Results: There were 246 patients (24.1%) undergoing single-session multivessel PCI, and 775 patients (75.9%) undergoing staged multivessel PCI. There was a wide variation in the prevalence of single-session multivessel PCI across the participating centers. The staged multivessel PCI group more often had complex coronary anatomy such as 3-vessel disease, chronic total occlusion, and calcified lesions requiring an atherectomy device compared with the single-session multivessel PCI group. The rates of PCI success, procedural complications, and meeting OPTIVUS criteria were not different between groups. The cumulative 1-year incidence of the primary endpoint was not different between single-session and staged multivessel PCI groups (9.0% vs 10.8%, log-rank P = 0.42). After adjusting confounders, the effect of single-session multivessel PCI relative to staged multivessel PCI was not significant for the primary endpoint (HR: 0.95; 95% CI: 0.58-1.55; P = 0.84). Conclusions: Single-session and staged multivessel IVUS-guided PCI had similar 1-year outcomes.

Optimal Intravascular Ultrasound-Guided Percutaneous Coronary Intervention in Patients With Multivessel Disease.

Background: Intravascular ultrasound (IVUS) was only rarely used in landmark trials comparing percutaneous coronary intervention (PCI) with coronary artery bypass grafting (CABG) in patients with multivessel disease. Objectives: The authors aimed to evaluate clinical outcomes after optimal IVUS-guided PCI in patients undergoing multivessel PCI. Methods: The OPTIVUS (OPTimal IntraVascular UltraSound)-Complex PCI study multivessel cohort was a prospective multicenter single-arm study enrolling 1,021 patients undergoing multivessel PCI, including left anterior descending coronary artery using IVUS, aiming to meet the prespecified criteria (OPTIVUS criteria: minimum stent area > distal reference lumen area [stent length ≥28mm], and minimum stent area >0.8 × average reference lumen area [stent length <28mm]) for optimal stent expansion. The primary endpoint was major adverse cardiac and cerebrovascular events (MACCE) (death/myocardial infarction/stroke/any coronary revascularization). The predefined performance goals were derived from the CREDO-Kyoto (Coronary REvascularization Demonstrating Outcome study in Kyoto) PCI/CABG registry cohort-2 fulfilling the inclusion criteria in this study. Results: In this study, 40.1% of the patients met OPTIVUS criteria in all stented lesions. The cumulative 1-year incidence of the primary endpoint was 10.3% (95% CI: 8.4%-12.2%), which was significantly lower than the predefined PCI performance goal of 27.5% (P < 0.001), and which was numerically lower than the predefined CABG performance goal of 13.8%. The cumulative 1-year incidence of the primary endpoint was not significantly different regardless of meeting or not meeting OPTIVUS criteria. Conclusions: Contemporary PCI practice conducted in the OPTIVUS-Complex PCI study multivessel cohort was associated with a significantly lower MACCE rate than the predefined PCI performance goal, and with a numerically lower MACCE rate than the predefined CABG performance goal at 1 year.

Target Lesion Revascularization After Intravascular Ultrasound-Guided Percutaneous Coronary Intervention.

BACKGROUND: Several stent expansion criteria derived from the intravascular ultrasound (IVUS) evaluation have been proposed to predict future clinical outcomes, but optimal stent expansion criteria as a guide during percutaneous coronary intervention (PCI) are still controversial. There are no studies evaluating the utility of stent expansion criteria along with the clinical and procedural factors in predicting target lesion revascularization (TLR) after contemporary IVUS-guided PCI. METHODS: OPTIVUS-Complex PCI study (Optimal Intravascular Ultrasound Guided Complex Percutaneous Coronary Intervention) multivessel cohort was a prospective multicenter study enrolling 961 patients undergoing multivessel PCI including left anterior descending coronary artery using IVUS with an intention to meet the prespecified criteria for optimal stent expansion. We compared several stent expansion criteria (minimum stent area [MSA], MSA/distal or average reference lumen area, MSA/distal or average reference vessel area, OPTIVUS criteria, IVUS-XPL [Impact of Intravascular Ultrasound Guidance on Outcomes of Xience Prime Stents in Long Lesions] criteria, ULTIMATE [Intravascular Ultrasound Guided Drug Eluting Stents Implantation in "All-Comers" Coronary Lesions] criteria, and modified MUSIC [Multicenter Ultrasound Stenting in Coronaries Study] criteria) as well as clinical, angiographic, and procedural characteristics between lesions with and without TLR. RESULTS: Among 1957 lesions, the cumulative 1-year incidence of lesion-based TLR was 1.6% (30 lesions). Hemodialysis, treatment of proximal left anterior descending coronary artery lesions, calcified lesions, small proximal reference lumen area, and small MSA had univariate associations with TLR, while all of the stent expansion criteria except for MSA were not associated with TLR. The independent risk factors of TLR were calcified lesions (hazard ratio, 2.34 [95% CI, 1.03-5.32]; P=0.04) and small proximal reference lumen area (Tertile 1: hazard ratio, 7.01 [95% CI, 1.45-33.93]; P=0.02; and Tertile 2: hazard ratio, 5.40 [95% CI, 1.17-24.90]; P=0.03). CONCLUSIONS: In contemporary IVUS-guided PCI practice, the 1-year incidence of TLR was very low. MSA, but not other stent expansion criteria, had univariate association with TLR. Independent risk factors of TLR were calcified lesions and small proximal reference lumen area, although the findings should be interpreted with caution due to small number of TLR events, limited lesion complexity, and short duration of follow-up.

[Current percutaneous coronary intervention technology for management of coronary artery disease].

Enormous advance was obtained in the field of percutaneous coronary intervention, treatment for coronary artery disease. Drug eluting stent (DES) offers advantages over bare metal stent (BMS) such as reduction in restenosis rates. However, several concerns were proposed when compared with BMS. Currently, numerous technologies are under development to avert the complications of DES, such as stent thrombosis, or to challenge complex lesion, such as left main trunk/bifurcation. We summarized some of the development that is emerging on current management of coronary intervention.

Analysis of left main coronary artery bifurcation lesions treated with biolimus-eluting DEVAX AXXESS plus nitinol self-expanding stent: intravascular ultrasound results of the AXXENT trial.

OBJECTIVE: To assess the efficacy of the AXXESS stent on the treatment of left main coronary artery (LMCA) bifurcation lesions using IVUS. BACKGROUND: The treatment of LMCA bifurcation lesions remains challenging even with the use of drug-eluting stents. The AXXESS system is a biolimus A9-eluting self-expanding stent, dedicated to the treatment of bifurcation lesions. METHODS: Data were obtained from the AXXENT trial, a prospective, single-arm, multicenter study designed to evaluate the efficacy of the AXXESS stent on the treatment of LMCA bifurcation lesions. IVUS was available in 26 cases at 6-months follow-up. Volumetric and cross-sectional analyses within the AXXESS stent, and cross-sectional analyses at the ostia of left anterior descending (LAD) and left circumflex coronary arteries (LCX) were performed. RESULTS: Within the AXXESS stent, percent neointimal volume obstruction was (3.0 +/- 4.1)% with a minimal lumen area of 10.3 +/- 2.6 mm(2). AXXESS stent volume showed an 12.4% increase at follow-up compared with postprocedure (P = 0.04). Lumen area was significantly smaller in the LCX ostium compared with the LAD ostium at follow-up (3.6 +/- 1.3 mm(2) vs. 5.5 +/- 2.0 mm(2), P = 0.0112). There was greater neointimal formation in the LCX ostium compared with the LAD ostium (1.37 +/- 1.20 mm(2) vs. 0.30 +/- 0.36 mm(2), P = 0.0003). CONCLUSIONS: The AXXESS stent in the LMCA showed enlargement through 6-months follow-up and significant neointimal suppression. Greater neointimal formation and relatively inadequate stent expansion may contribute to luminal narrowing in the LCX ostium.

Comparison of vascular response to zotarolimus-eluting stent versus sirolimus-eluting stent: intravascular ultrasound results from ENDEAVOR III.

BACKGROUND: The purpose of this study was to investigate the vascular response of zotarolimus-eluting stent (ZES) and sirolimus-eluting stent (SES) using serial intravascular ultrasound (IVUS). METHODS: Data were obtained from the Endeavor Drug-Eluting Coronary Stent System Versus the Center Siromlimus-Eluting Coronary Stent System in De Novo Native Coronary Artery Lesions (ENDEAVOR) III trial, a randomized study comparing ZES and SES for the treatment of de novo native coronary artery lesions. Serial (baseline and 8-month follow-up) IVUS was available in 258 patients (190 ZES, 68 SES). RESULTS: At 8 months, ZES had greater percentage of neointimal volume index (ZES 1.1 +/- 0.8 mm3/mm vs SES 0.2 +/- 0.1 mm3/mm, P < .01), resulting in smaller lumen volume index (6.0 +/- 2.0 mm3/mm vs 7.0 +/- 2.1 mm3/mm, P < .05). Zotarolimus-eluting stents showed larger IVUS-detectable neointimal coverage over stent surface (50.2% vs 10.5%, P < .01) and greater mean neointimal thickness (0.19 +/- 0.07 mm vs 0.10 +/- 0.06 mm, P < .01). Zotarolimus-eluting stents had a significantly lower incidence of late-acquired incomplete stent apposition. CONCLUSIONS: Zotarolimus-eluting stent is associated with a significantly greater amount of neointimal hyperplasia compared with SES. This amount of hyperplasia in ZES is distributed throughout the stent at 8-month follow-up.

Validity of the Low-Impact Dance for exercise-based cardiac rehabilitation program.

PURPOSE: The aim of this study was to evaluate the oxygen uptake in patients with cardiovascular disease during the low-impact dance program and to compare the findings with the values at peak oxygen uptake (VO2) and aerobic threshold (AT). METHODS: The study included 19 patients with cardiovascular disease [age, 68.3±8.7 years; left-ventricular ejection fraction, 60.3%±8.7%; peak VO2, 6.6±1.1 metabolic equivalents (METs)] who were receiving optimal medical treatment. Their heart rate and VO2 were monitored during cardiopulmonary exercise testing (CPET) and during the low impact dance. The dance involved low-impact dynamic sequences. The patients completed two patterns of low-impact dance, and metabolic gas exchange measurements were obtained using a portable ergospirometry carried in a backpack during the dance sessions. RESULTS: The mean values of VO2 (4.0±0.2 METs and 3.9±0.3 METs) and those of heart rate (105.2±2.9 bpm and 96.8±2.6 bpm) during the dance program were not significantly differ from the AT value (4.5±0.2 METs) obtained in CPET. The median (and interquartile range) RPE reported after the dance exercise trials was 11 (9-13). No signs of overexertion were observed in any of the patients during either dance exercise trial. CONCLUSIONS: The results suggest that it is reasonable to consider the low-impact dance program as an aerobic exercise program in cardiac rehabilitation. Our findings have important implications for exercise training programs in the cardiac rehabilitation setting and for future studies.

Impact of gender on neointimal hyperplasia following coronary artery stenting.

Whether gender affects long-term outcomes after bare metal stent implantation remains controversial. The aim of this study was to examine the impact of gender on neointimal hyperplasia in a large cohort of patients after stent implantation using 3-dimensional intravascular ultrasound. Lumen and stent areas were manually traced at 0.5-mm intervals throughout the stented segment. Using Simpson's method, lumen, stent, and neointimal (stent - lumen) volumes were calculated and standardized by stent length. Women were older, presented more often with hyperlipidemia or hypertension, and had smaller reference vessel diameter and mean stent area, compared with men. Although neointimal hyperplasia and neointimal thickness in women were similar to that in men, the percentage of neointimal hyperplasia (neointimal area divided by stent area) was higher in women due to the smaller stent area. After adjusting for stent area, the percentage of neointimal hyperplasia did not differ by gender. In conclusion, the results of this study indicate that neointimal hyperplasia after bare metal stent implantation in women is similar to that seen in men. Despite the similarity in outcome, there are several gender-specific differences in baseline characteristics.

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.

Effects of sitagliptin on coronary atherosclerosis in patients with type 2 diabetes-A serial integrated backscatter-intravascular ultrasound study.

Dipeptidyl peptidase-4 (DPP-4) inhibitors have demonstrated anti-inflammatory and anti-atherogenic effects in an animal model. However, the clinical usefulness of DPP-4 inhibitors, particularly its effects on coronary atherosclerosis, has not been evaluated thus far. Therefore, in this study, we evaluated the effects of sitagliptin, a DPP-4 inhibitor, on coronary atherosclerosis using integrated backscatter (IB)-intravascular ultrasound (IVUS) in patients with type 2 diabetes. This trial was a prospective, open-labeled, randomized, multicenter study. Twenty-eight patients with type 2 diabetes who underwent elective percutaneous coronary intervention (PCI) were randomly assigned to either the sitagliptin group (group S) or the control group (group C). Non-PCI lesions were evaluated using IB-IVUS at the time of PCI and at the 48-week follow-up. The primary endpoint was the percentage change in plaque volume measured using grayscale IVUS, and the secondary endpoint was changes in plaque composition evaluated using IB-IVUS. Grayscale IVUS analysis demonstrated that plaque volume tended to decrease in both groups (group S: -1.7±8.5%; group C: -3.2±12.2%), but a between-group difference was not observed. A decrease in the lipid plaque volume (group S: from 200.1±116.2 to 179.8±121.0 mm3, P = 0.02; group C: from 298.3±363.0 to 256.6±386.1 mm3, P = 0.1) and an increase in the calcified plaque volume (group S: from 2.1±0.9 to 3.2±1.8 mm3, P = 0.06; group C: from 2.3±1.7 to 4.8±3.5 mm3, P = 0.04) was observed on IB-IVUS analysis. Univariate and multivariate regression analyses showed that the percentage change in serum non-high-density lipoprotein (HDL) cholesterol level was an independent and significant predictor of a reduction in lipid plaque volume (ß = 0.445, P = 0.04). In conclusions, sitagliptin did not significantly reduce coronary plaque volume in patients with type 2 diabetes. However, a decrease in the lipid plaque volume was observed in the sitagliptin group. A decrease in non-HDL cholesterol level was associated with a reduction in the lipid volume of coronary artery plaques.

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.

The impact of metallic allergy on stent implantation: metal allergy and recurrence of in-stent restenosis.

BACKGROUND: Relation between metallic allergy and in-stent restenosis (ISR) has been inconclusive. We hypothesized that mechanism of restenosis is different between initial stent implantation and dilatation for ISR. Thus, we studied metallic allergy and restenosis in these two different situations separately. METHODS AND RESULTS: We performed follow-up angiography and patch test for metallic allergy in a total of 174 stented consecutive patients, 109 patients (63%) for restudy of initial stent implantation and 65 patients (37%) for restudy of treatment following ISR. The positive rate of patch test in initial stent implantation was not significantly different between with or without restenosis (10% vs. 9%; p=ns). Whereas, following dilatation of ISR, the incidence of positive patch test was significantly higher in patients with recurrence of restenosis than those without the recurrence (39% vs. 12%; p=0.02). Multivariate analysis revealed that the positive patch test (Odd Ratio 4.39, p=0.02) and diffuse typed ISR (Odd Ratio 3.68, p=0.03) were significant predictors of recurrent restenosis. CONCLUSIONS: Metal allergy does not have any correlation with the restenosis after initial stent implantation. However, metal allergy is frequently observed in patients with recurrence of ISR. Metal allergy may contribute to a mechanism in the repeat recurrence of ISR, but not to restenosis after initial stent implantation.

Outcomes of everolimus-eluting stent incomplete stent apposition: a serial optical coherence tomography analysis.

AIM: The aim of the present study was to evaluate the natural course of acute incomplete stent apposition (ISA) after second-generation everolimus-eluting stent (EES) when compared with first-generation sirolimus-eluting stent (SES) by using optical coherence tomography (OCT). METHODS AND RESULTS: From the OCT substudy of the RESET trial, we identified 77 patients (EES = 38 and SES = 39) who successfully underwent serial OCT examination at post-stenting and 8-12-month follow-up. The presence of ISA was assessed in the OCT images, and ISA distance was measured from the centre of the strut blooming to the adjacent lumen border. Incomplete stent apposition was observed in all EES and SES at post-stenting, and it was persistent in 26% of EES and 38% of SES at 8-12-month follow-up. Maximum ISA distance was significantly decreased during the follow-up period in both EES (315 ± 94-110 ± 165 µm, P < 0.001) and SES (308 ± 119-143 ± 195 µm, P < 0.001). Receiver-operating curve analysis identified that the best cut-off value of OCT-estimated ISA distance at post-stenting for predicting late-persistent ISA at 8-12-month follow-up in EES and SES was >355 and >285 µm, respectively. CONCLUSIONS: The second-generation EES showed better healing of acute ISA in comparison with the first-generation SES. Optical coherence tomography can predict late-persistent ISA after DES implantation and provide useful information to optimize PCI.

Initial characterization of Ikari Guide catheter for transradial coronary intervention.

Ikari is a new guide catheter for transradial intervention (TRI) that produces stronger back-up force by utilizing an unfavorable angle between the subclavian and brachiocephalic arteries. We report the initial results of the Ikari guide catheter based on the experience of a single center. Six operators performed a total of 102 coronary interventions for 91 patients using the Ikari guide catheter, while 101 interventions were performed with the transfemoral approach (TFI) during the same period. A left Ikari catheter was used in 63 procedures, and a right Ikari catheter was used in 39. The success rate for the procedure was 97% with a 6 French Ikari catheter. All failures were due to tortuous brachiocephalic arteries. For the Ikari procedure, the average fluorescence time was 14.5 9.5 minutes and the dye volume used was 153 53 ml; these results were equal to or better than those of TFI during the same period (20.1 12.2 minutes and 184 61 ml, respectively). These preliminary data suggest that an acceptable success rate can be achieved in TRI using appropriate guides, such as an Ikari catheter.