Tomomi Koizumi

In Vivo Comparison Between Optical Coherence Tomography and Intravascular Ultrasound for Detecting Small Degrees of In-Stent Neointima After Stent Implantation

OBJECTIVES The purpose of this study was to evaluate optical coherence tomography (OCT) for detecting small degrees of in-stent neointima (ISN) after stent implantation compared with intravascular ultrasound (IVUS). BACKGROUND The importance of detecting neointimal coverage of stent struts has grown with the appreciation of the increased risk for late stent thrombosis after drug-eluting stent (DES) implantation. Intravascular ultrasound, the current standard for evaluating the status of DES, lacks the resolution to detect the initial neointimal coverage. Optical coherence tomography has greater resolution but has not yet been compared with IVUS in vivo with histological correlation for validation. METHODS Intravascular ultrasound and OCT were performed with motorized pullback imaging in 6 pigs across 33 stents, 1 month after implantation. Each pig was euthanized, and histological measurements of vessel, stent, and lumen dimensions were performed in 3 sections of each stent. A small degree of ISN was defined as occupying <30% of the stent area measured with histology. The IVUS, OCT, and histological assessment of ISN were compared in matched cross-sections of the stents with a small degree of ISN. RESULTS Eleven stents had a small degree of ISN (average ISN area: 1.26 +/- 0.46 mm(2), and percent area obstruction: 21.4 +/- 5.2%). Compared with histology, the diagnostic accuracy of OCT (area under the receiver operating characteristic curve [AUC] = 0.967, 95% confidence interval [CI] 0.914 to 1.019) was higher than that of IVUS (AUC = 0.781, 95% CI 0.621 to 0.838). CONCLUSIONS Optical coherence tomography detects smaller degrees of ISN more accurately than IVUS and might be a useful method for identifying neointimal coverage of stent struts after DES implantation.

Impact of Polymer Formulations on Neointimal Proliferation After Zotarolimus-Eluting Stent With Different Polymers Insights From the RESOLUTE Trial

Background— Polymer formulation may affect the efficacy of drug-eluting stents. Resolute, Endeavor, and ZoMaxx are zotarolimus-eluting stents with different stent platforms and different polymer coatings and have been tested in clinical trials. The aim of this analysis was to compare the efficacy of zotarolimus-eluting stents with different polymers. Methods and Results— Data were obtained from the first-in man trial or first randomized trials of each stent, The Clinical RESpOnse EvaLUation of the MedTronic Endeavor CR ABT-578 Eluting Coronary Stent System in De Novo Native Coronary Artery Lesions (RESOLUTE), Randomized Controlled Trial to Evaluate the Safety and Efficacy of the Medtronic AVE ABT-578 Eluting Driver Coronary Stent in De Novo Native Coronary Artery Lesions (ENDEAVOR II), and ZoMaxx I trials. Follow-up intravascular ultrasound analyses (8 to 9 months of follow-up) were possible in 353 patients (Resolute: 88, Endeavor: 98, ZoMaxx: 82, Driver: 85). Volume index (volume/stent length) was obtained for vessel, stent, lumen, peristent plaque, and neointima. Cross-sectional narrowing was defined as neointimal area divided by stent area (%). Neointima-free frame ratio was calculated as the number of frames without intravascular ultrasound–detectable neointima divided by the total number of frames within the stent. At baseline, vessel, lumen, and peristent plaque volume index were not significantly different among the 4 stent groups. At follow-up, percent neointimal obstruction was significantly lower in Resolute compared with Endeavor, ZoMaxx, and Driver (Resolute: 3.7±4.0, Endeavor: 17.5±10.1, ZoMaxx: 14.6±8.1, Driver: 29.4±17.2%; P<0.001). Greater maximum cross-sectional narrowing and higher neointima-free frame ratio, suggesting less neointimal coverage, were observed in Resolute compared with other stent groups. Multiple regression analysis confirmed that the biodurable polymer used in Resolute independently correlated with neointimal suppression among 3 zotarolimus-eluting stents. Conclusions— The different polymer formulations significantly affect the relative amount of neointima for zotarolimus-eluting stents. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00248079.

Impact of Polymer Formulations on Neointimal Proliferation After Zotarolimus-Eluting Stent With Different PolymersClinical Perspective

Background— Polymer formulation may affect the efficacy of drug-eluting stents. Resolute, Endeavor, and ZoMaxx are zotarolimus-eluting stents with different stent platforms and different polymer coatings and have been tested in clinical trials. The aim of this analysis was to compare the efficacy of zotarolimus-eluting stents with different polymers. Methods and Results— Data were obtained from the first-in man trial or first randomized trials of each stent, The Clinical RESpOnse EvaLUation of the MedTronic Endeavor CR ABT-578 Eluting Coronary Stent System in De Novo Native Coronary Artery Lesions (RESOLUTE), Randomized Controlled Trial to Evaluate the Safety and Efficacy of the Medtronic AVE ABT-578 Eluting Driver Coronary Stent in De Novo Native Coronary Artery Lesions (ENDEAVOR II), and ZoMaxx I trials. Follow-up intravascular ultrasound analyses (8 to 9 months of follow-up) were possible in 353 patients (Resolute: 88, Endeavor: 98, ZoMaxx: 82, Driver: 85). Volume index (volume/stent length) was obtained for vessel, stent, lumen, peristent plaque, and neointima. Cross-sectional narrowing was defined as neointimal area divided by stent area (%). Neointima-free frame ratio was calculated as the number of frames without intravascular ultrasound–detectable neointima divided by the total number of frames within the stent. At baseline, vessel, lumen, and peristent plaque volume index were not significantly different among the 4 stent groups. At follow-up, percent neointimal obstruction was significantly lower in Resolute compared with Endeavor, ZoMaxx, and Driver (Resolute: 3.7±4.0, Endeavor: 17.5±10.1, ZoMaxx: 14.6±8.1, Driver: 29.4±17.2%; P<0.001). Greater maximum cross-sectional narrowing and higher neointima-free frame ratio, suggesting less neointimal coverage, were observed in Resolute compared with other stent groups. Multiple regression analysis confirmed that the biodurable polymer used in Resolute independently correlated with neointimal suppression among 3 zotarolimus-eluting stents. Conclusions— The different polymer formulations significantly affect the relative amount of neointima for zotarolimus-eluting stents. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00248079.

Intramural Hematoma Appearing as a New Lesion After Coronary Stenting

A 51-year-old man with hypertension and hyperlipidemia presented with exertional chest pain and underwent a stress echocardiogram that showed anterior and lateral ischemia. Coronary angiography revealed a 70% stenosis of the mid left circumflex artery and an 80% stenosis of the proximal left

Differing Behavior of Plasma Pentraxin3 and High-Sensitive CRP at theVery Onset of Myocardial Infarction with ST-segment Elevation

Although pentraxin3 (PTX3) has been reported as marker of more directly reflect the vascular inflammatory status than short pentraxin including high-sensitive CRP (hs-CRP), detailed difference in blood levels between PTX3 and hs-CRP at the onset of ST-segment elevation myocardial infarction (STEMI) are not fully investigated. Blood levels of pentraxins (PTX3 and hs-CRP) in 20 patients with early arrival of STEMI (2.9 ± 2.2 hours after onset) were measured at baseline, 24, 48, 72 and 120 hours after primary percutaneous coronary intervention (PCI). Also, the blood levels in infarct-related artery (IRA) were measured by thrombus aspiration during PCI. Samples of control (not myocardial infarction) with normal coronary artery (n=10) were drawn from both coronary and peripheral arteries during diagnostic coronary angiography. At baseline, the levels of PTX3 in both femoral and coronary artery in STEMI were significantly higher than those in control, but the hs-CRP did not different between STEMI and control. The level of both PTX3 and hs-CRP did not different between femoral artery and IRA in STEMI patients at baseline. Systemic level of PTX3 peaked 24 hours (p=0.01) followed by the hs-CRP that peaked 48 hours (p<0.01) after the PCI. PTX3 had appeared earlier than hs-CRP in the systemic circulation in the STEMI patients, but they may not be locally released from the IRA.

Impact of Polymer Formulations on Neointimal Proliferation After Zotarolimus-Eluting Stent With Different Polymers

Background— Polymer formulation may affect the efficacy of drug-eluting stents. Resolute, Endeavor, and ZoMaxx are zotarolimus-eluting stents with different stent platforms and different polymer coatings and have been tested in clinical trials. The aim of this analysis was to compare the efficacy of zotarolimus-eluting stents with different polymers. Methods and Results— Data were obtained from the first-in man trial or first randomized trials of each stent, The Clinical RESpOnse EvaLUation of the MedTronic Endeavor CR ABT-578 Eluting Coronary Stent System in De Novo Native Coronary Artery Lesions (RESOLUTE), Randomized Controlled Trial to Evaluate the Safety and Efficacy of the Medtronic AVE ABT-578 Eluting Driver Coronary Stent in De Novo Native Coronary Artery Lesions (ENDEAVOR II), and ZoMaxx I trials. Follow-up intravascular ultrasound analyses (8 to 9 months of follow-up) were possible in 353 patients (Resolute: 88, Endeavor: 98, ZoMaxx: 82, Driver: 85). Volume index (volume/stent length) was obtained for vessel, stent, lumen, peristent plaque, and neointima. Cross-sectional narrowing was defined as neointimal area divided by stent area (%). Neointima-free frame ratio was calculated as the number of frames without intravascular ultrasound–detectable neointima divided by the total number of frames within the stent. At baseline, vessel, lumen, and peristent plaque volume index were not significantly different among the 4 stent groups. At follow-up, percent neointimal obstruction was significantly lower in Resolute compared with Endeavor, ZoMaxx, and Driver (Resolute: 3.7±4.0, Endeavor: 17.5±10.1, ZoMaxx: 14.6±8.1, Driver: 29.4±17.2%; P<0.001). Greater maximum cross-sectional narrowing and higher neointima-free frame ratio, suggesting less neointimal coverage, were observed in Resolute compared with other stent groups. Multiple regression analysis confirmed that the biodurable polymer used in Resolute independently correlated with neointimal suppression among 3 zotarolimus-eluting stents. Conclusions— The different polymer formulations significantly affect the relative amount of neointima for zotarolimus-eluting stents. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00248079.

Intravascular ultrasound insights from the Cobalt Chromium Stent With Antiproliferative for Restenosis II (COSTAR II) trial comparing CoStar and Taxus paclitaxel-eluting stents

BACKGROUND Dedicated IVUS analyses of the second CObalt chromium STent with Antiproliferative for Restenosis (COSTAR II) trial have not been documented. We aim to compare IVUS findings between CoStar paclitaxel-eluting stent (PES) and Taxus PES in patients enrolled in the COSTAR II trial. We also attempted to examine the possible regional impact of multiple stenting. METHODS AND MATERIALS Among the 1700 patients enrolled, 238 were assigned to an IVUS cohort including 168 patients treated by provisional multiple stenting. At 9 months, qualitative and quantitative IVUS observations including incomplete stent apposition (ISA) and neointimal proliferation (neointimal obstruction: neointimal volume/stent volume ×100) were compared between CoStar and Taxus PESs. RESULTS In qualitative analysis, late-acquired ISA was observed in 1 patient treated by Taxus PES. Impaired strut continuity suggestive of stent fracture was observed in 2 out of 33 patients treated by multiple CoStar, and 4 out of 21 patients treated by multiple Taxus (P=.14). No such findings were found in single-stented patients in either stent subset. Quantitative analysis showed greater neointimal obstruction in CoStar (19.7%±13.4%, n=52) than in Taxus (10.7%±9.9%, n=38), whereas no significant difference in neointimal obstruction was found between single and multiple stenting in either CoStar or Taxus PES. CONCLUSIONS The CoStar PES exhibits greater neointimal proliferation compared with Taxus PES at 9 months but with similar qualitative outcomes including late-acquired ISA. IVUS findings suggestive of stent fracture were found only in multiple-stenting cases irrespective of the stent used.

Vascular responses to the multiple overlapped paclitaxel-eluting stents for the treatment of bare-metal in-stent restenotic lesions: angiographic and intravascular ultrasound analysis from the TAXUS-V ISR Trial

BACKGROUND Although effective coverage of coronary diffuse in-stent restenosis (ISR) lesions has warranted the use of multiple drug-eluting stents, the vessel response to paclitaxel-eluting stent (PES) overlap is not fully understood. METHODS AND MATERIALS In the TAXUS-V ISR, i.e., comparing PES versus brachytherapy for the treatment of bare-metal ISR, angiographic analyses at 9-month follow-up were available in 184 ISR lesions treated with PES. RESULTS In-stent late loss in entire stented segment of multiple PES (n=50) was 0.45+/-0.48 mm, whereas that of single PES (n=134) was 0.3+/-0.47 mm, P=.06. No aneurysm was observed at overlapping PES segments at 9 months. Stent thrombosis up to 9 months was observed in one in each group (single PES, 0.7% vs. multiple PES, 1.8%; P=.47). In a subset of 30 patients, volumetric intravascular ultrasound analysis demonstrated that in-stent net volume obstruction was 12.3+/-12.4 in single PES (n=20) and 14.9+/-9.8 in multiple PES (n=10), P=.60. The changes of vessel and lumen at the overlapping PES segment were similar to those of the adjacent 5-mm segments (Deltaminimum lumen area, mm(2): -1.2+/-1.0, -1.1+/-1.1, -0.8+/-0.9, P=.48; Deltavessel volume, mm(3)/mm: -0.2+/-1.4, 0.1+/-1.7, 0.3+/-1.3, P=.37; proximal, overlap, distal segment, respectively). There was no late incomplete stent apposition at overlapping PES segments. CONCLUSIONS No in vivo evidence of adverse local vessel response at the site of overlapping PES for the treatment of bare-metal ISR has been demonstrated.

Latent plaque rupture in a patient undergoing stenting for acute coronary syndrome and diffuse coronary disease: a case report and review of literature.

Secondary prevention of plaque rupture following percutaneous coronary intervention in patients with acute coronary syndrome is not well studied. This case report describes a 53‐year‐old man who experienced plaque rupture between two previously successfully implanted stents in the right coronary artery, as documented during the 3rd intervention using intravascular ultrasound.

Impact of Polymer Formulations on Neointimal Proliferation After Zotarolimus-Eluting Stent With Different PolymersClinical Perspective: Insights From the RESOLUTE Trial

Background— Polymer formulation may affect the efficacy of drug-eluting stents. Resolute, Endeavor, and ZoMaxx are zotarolimus-eluting stents with different stent platforms and different polymer coatings and have been tested in clinical trials. The aim of this analysis was to compare the efficacy of zotarolimus-eluting stents with different polymers. Methods and Results— Data were obtained from the first-in man trial or first randomized trials of each stent, The Clinical RESpOnse EvaLUation of the MedTronic Endeavor CR ABT-578 Eluting Coronary Stent System in De Novo Native Coronary Artery Lesions (RESOLUTE), Randomized Controlled Trial to Evaluate the Safety and Efficacy of the Medtronic AVE ABT-578 Eluting Driver Coronary Stent in De Novo Native Coronary Artery Lesions (ENDEAVOR II), and ZoMaxx I trials. Follow-up intravascular ultrasound analyses (8 to 9 months of follow-up) were possible in 353 patients (Resolute: 88, Endeavor: 98, ZoMaxx: 82, Driver: 85). Volume index (volume/stent length) was obtained for vessel, stent, lumen, peristent plaque, and neointima. Cross-sectional narrowing was defined as neointimal area divided by stent area (%). Neointima-free frame ratio was calculated as the number of frames without intravascular ultrasound–detectable neointima divided by the total number of frames within the stent. At baseline, vessel, lumen, and peristent plaque volume index were not significantly different among the 4 stent groups. At follow-up, percent neointimal obstruction was significantly lower in Resolute compared with Endeavor, ZoMaxx, and Driver (Resolute: 3.7±4.0, Endeavor: 17.5±10.1, ZoMaxx: 14.6±8.1, Driver: 29.4±17.2%; P<0.001). Greater maximum cross-sectional narrowing and higher neointima-free frame ratio, suggesting less neointimal coverage, were observed in Resolute compared with other stent groups. Multiple regression analysis confirmed that the biodurable polymer used in Resolute independently correlated with neointimal suppression among 3 zotarolimus-eluting stents. Conclusions— The different polymer formulations significantly affect the relative amount of neointima for zotarolimus-eluting stents. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00248079.