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Despite remarkable advances in the interventional landscape, device delivery during percutaneous coronary intervention (PCI) can still present technical challenges especially when performed in complex anatomical settings and through radial approach. To overcome difficult coronary stent delivery, several strategies have been developed. A niche option in such complex cases is the anchoring balloon technique, which involves inflation of a balloon non-coaxially in a side branch or distally to the target lesion in a coaxial fashion, to facilitate stent delivery. However, the main limitation of this technique is the requirement of a large guide catheter (≥7French) which may preclude the use of radial approach. We describe, step-by-step, the distal anchoring ballooning technique performed by a 6Fr radial approach to overcome the stent delivery failure in complex anatomical scenarios and to safely and successfully carry out the PCI procedures., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Randomized controlled trials assessing new drugs and devices tend to exclude subjects who are at greatest risk. The Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial incorporated broader inclusion criteria in an attempt to include a more representative spectrum of patients presenting with ST-segment elevation myocardial infarction (STEMI). To identify the differences between this modern trial and the real world, we analyzed the characteristics and outcomes of patients with STEMI who were screened but not enrolled at a high-volume recruiting center. Of 318 consecutive patients with STEMI who were screened, 200 (62.9%) were randomized, and 118 (37.1%) were excluded. The baseline characteristics and 30-day and 1-year clinical outcomes were compared in the 2 groups. The excluded patients had numerous high-risk features compared to those randomized, including being older (67.0 ± 12.8 vs 63.0 ± 11.4 years, p = 0.004), more often had had a previous MI (34.7% vs 8.0%, p <0.001), Killip class III-IV (27.4% vs 4.0%, p <0.001), and lower hemoglobin (13.4 ± 2.3 vs 14.8 ± 1.5 g/dl, p <0.001). The excluded patients had markedly greater 30-day and 1-year rates of all-cause mortality (17.4% vs 2.0%, p <0.001, and 27.6% vs 2.5%, p <0.001, respectively), major adverse cardiovascular events (death, MI, ischemia-driven target vessel revascularization, and stroke), major bleeding, and net adverse clinical events (major adverse cardiovascular events or major bleeding). On multivariate analysis, Killip class III-IV at presentation, age, left ventricular ejection fraction, and final Thrombolysis In Myocardial Infarction flow grade 3 were independent predictors of outcome. In conclusion, despite the broadened entry criteria of the HORIZONS-AMI trial, 37.1% of all patients presenting with STEMI at a center with a high rate of enrollment were judged to be ineligible and were excluded. The excluded patients had a significantly greater risk profile and markedly increased mortality and adverse events compared to the trial-eligible group., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Objectives: This study investigated the role of uncovered stent struts on late stent thrombosis (LST) after drug-eluting stent (DES) implantation with optical coherence tomography (OCT)., Background: Autopsy studies have identified delayed healing and lack of endothelialization of DES struts as the hallmarks of LST. DES strut coverage has not previously been examined in vivo in patients with LST., Methods: We studied 54 patients, including 18 with DES LST (median 615 days after implant) undergoing emergent percutaneous coronary interventions and 36 matched DES control subjects undergoing routine repeat OCT and intravascular ultrasound (IVUS) who did not experience LST for ≥3 years. Thrombus aspiration was performed during emergent percutaneous coronary intervention before OCT and IVUS assessment., Results: By OCT, patients with LST--compared with control subjects--had a higher percentage of uncovered (median [interquartile range]) (12.27 [5.50 to 23.33] vs. 4.14 [3.00 to 6.22], p < 0.001) and malapposed (4.60 [1.85 to 7.19] vs. 1.81 [0.00 to 2.99], p < 0.001) struts. The mean neointimal thickness was similar in the 2 groups (0.23 ± 0.17 mm vs. 0.17 ± 0.09 mm, p = 0.28). By IVUS, stent expansion was comparable in the 2 groups, although positive remodeling was increased in patients with LST (mean vessel cross-section area 19.4 ± 5.8 mm(2) vs. 15.1 ± 4.6 mm(2), p = 0.003). Thrombus aspiration demonstrated neutrophils and eosinophils in most cases. By multivariable analysis, the length of segment with uncovered stent struts by OCT and the remodeling index by IVUS were independent predictors of LST., Conclusions: In this in vivo case-controlled study, the presence of uncovered stent struts as assessed by OCT and positive vessel remodeling as imaged by IVUS were associated with LST after DES., (Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: The safety of drug-eluting stents in ST-segment elevation myocardial infarction (STEMI) continues to be debated. Pathological studies have demonstrated an association between uncovered struts and subsequent stent thrombosis. Optical coherence tomography can detect stent strut coverage in vivo on a micron-scale level. We therefore used optical coherence tomography to examine strut coverage in patients with STEMI treated with paclitaxel-eluting stents (PES) and bare metal stents (BMS)., Methods and Results: In the Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial, patients with STEMI were randomized 3:1 to PES or BMS implantation. In a formal substudy, optical coherence tomography at 13 months was performed in 118 consecutive randomized patients (89 PES, 29 BMS) in whom 188 stents were assessed (146 PES and 42 BMS). A total of 44 139 stent struts were analyzed by an independent core laboratory blinded to stent assignment. The primary prespecified end point, the percentage of uncovered stent struts per lesion at follow-up, was 1.1 ± 2.5% in BMS lesions versus 5.7 ± 7.0% in PES lesions (P < 0.0001). Malapposed struts were observed in 0.1 ± 0.2% of BMS lesions versus 0.9 ± 2.1% of PES lesions (P = 0.0003). Percentage net volume obstruction was 36.0 ± 15.4% with BMS and 19.2 ± 11.3% with PES (P < 0.0001)., Conclusions: In patients with STEMI undergoing primary percutaneous coronary intervention, implantation of PES as compared with BMS significantly reduces neointimal hyperplasia but results in higher rates of uncovered and malapposed stent struts as assessed by optical coherence tomography at 13-month follow-up. Further studies are required to determine the clinical significance of these findings., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00433966.

Objectives: Using optical coherence tomography, we assessed the proportion of uncovered struts at 6-month follow-up in zotarolimus-eluting stents (ZES), specifically Endeavor (Medtronic CardioVascular, Santa Rosa, California) stents, and identical bare-metal stents (BMS) implanted in patients with ST-segment elevation myocardial infarction (STEMI)., Background: Sirolimus- and paclitaxel-eluting stents implanted in STEMI have been associated with delayed healing and incomplete strut coverage. ZES are associated with a more complete and uniform strut coverage in stable patients, but whether this holds true also after STEMI is unknown., Methods: Forty-four patients with STEMI who underwent primary PCI were randomized to ZES or BMS (3:1 randomization). Angiographic, intravascular ultrasound, and optical coherence tomography follow-up was conducted at 6 months and clinical follow-up at 1 year. All images were analyzed by an independent core laboratory that was blind to stent assignments., Results: There were no differences between ZES and BMS in percentage of uncovered struts (median: 0.00% [interquartile range (IQR): 0.00% to 1.78%] vs. 1.98% [IQR: 0.21% to 7.33%], p = 0.13), maximum length of uncovered segments (0.00 [IQR: 0.00 to 1.19] mm vs. 1.38 [IQR: 0.65 to 3.30] mm, p = 0.10), percentage of malapposed struts (0.00% [IQR: 0.00% to 0.23%] vs. 0.15% [IQR: 0.00% to 5.81%], p = 0.16), and maximum length of malapposed segments (0.00 [IQR: 0.00 to 0.67] mm vs. 0.33 [IQR: 0.00 to 2.55] mm, p = 0.20). Neointimal response was similar between ZES and BMS (332 [IQR: 240 to 429] microm vs. 186 [IQR: 136 to 348] microm, p = 0.99) and evenly distributed. No late acquired malapposition was observed in both groups. There were no deaths, myocardial infarction, or stent thromboses at 1 year., Conclusions: This optical coherence tomography study found no difference in strut coverage and similar vessel response to ZES, when compared with identical BMS, implanted during primary percutaneous coronary intervention in STEMI patients. (Six-Month Coverage and Vessel Wall Response of the Zotarolimus Drug-Eluting Stent Implanted in AMI Assessed by Optical Coherence Tomography [OCTAMI]; NCT00704561)., (Copyright 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objectives: We designed a randomized trial exploiting optical coherence tomography (OCT) to assess coverage and apposition of overlapping bare-metal stents (BMS) and drug-eluting stents (DES) in human coronary arteries., Background: Overlapping DES impair healing in animals. Optical coherence tomography allows accurate in vivo assessment of stent strut coverage and apposition., Methods: Seventy-seven patients with long coronary stenoses were randomized to overlapping sirolimus-eluting stents (SES), paclitaxel-eluting stents (PES), zotarolimus-eluting stents (ZES), or BMS. The primary goal of the study was to determine the rate of uncovered/malapposed struts in overlap versus nonoverlap segments, according to stent type, at 6-month follow-up with OCT., Results: A total of 53,047 struts were analyzed. The rate of uncovered/malapposed struts was 1.5 +/- 3.4% and 0.6 +/- 2.7% in overlap versus nonoverlap BMS (p = NS), respectively, and 4.3 +/- 11% and 3.6 +/- 8% in overlap versus nonoverlap DES (p = NS), respectively. There were no differences in the rates of uncovered/malapposed struts between overlapping BMS and DES, likely due to low frequency of uncovered/malapposed struts in ZES (0.1 +/- 0.4%), which offset the higher rates observed in SES (6.7 +/- 9.6%) and PES (6.7 +/- 16.5%, p < 0.05). Overlap segments showed greater neointimal volume obstruction versus nonoverlap segments in all DES (p < 0.05 for all DES types). Strut-level neointimal thickness at overlap and nonoverlap segments were lowest in SES (0.16 +/- 0.1 mm and 0.12 +/- 0.1 mm, respectively) compared with PES (0.27 +/- 0.1 mm and 0.20 +/- 0.1 mm, respectively), ZES (0.40 +/- 0.16 mm and 0.33 +/- 0.13 mm, respectively), and BMS (0.55 +/- 0.31 mm and 0.53 +/- 0.25 mm, respectively, p < 0.05)., Conclusions: As assessed by OCT the impact of DES on vascular healing was similar at overlapping and nonoverlapping sites. However, strut malapposition, coverage pattern, and neointimal hyperplasia differ significantly according to DES type. (Optical Coherence Tomography for Drug Eluting Stent Safety [ODESSA]; NCT00693030)., (Copyright 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Aims: We sought to evaluate the vascular response of stent struts deployed in bifurcation segments using optical coherence tomography (OCT)., Methods and Results: This study is a sub-analysis of ODESSA, a prospective randomised trial designed to evaluate healing of overlapped drug-eluting stents (DES) vs. bare metal stents (BMS) (sirolimus SES: paclitaxel PES: zotarolimus ZES: Liberté BMS in a 2: 2: 2: 1 ratio) for de novo coronary artery stenosis. OCT was performed at 6-month follow-up. Bifurcation segments with side branch diameters larger than 1.5mm by angiography were analysed. The cross-sectional image at the bifurcation segment was divided into three regions: opposite to the ostium (OO), adjacent to the ostium (AO), or side-branch ostium (SO). Struts were classified in three categories: uncovered (U), covered (C), or proliferative (P). The incidence of each strut category was compared between regions and stent types. There were 12,656 struts in 61 bifurcation segments (PES: 16, SES: 14, ZES: 23, Liberté BMS: 8) from 46 patients obtained at six months. PES had the highest rate of U in SO region (PES 60.1, SES 17.0, ZES 13.2, BMS 12.3 (%), P<0.0001), whereas SES demonstrated the highest rate of U in OO (PES 3.8, SES 14.0, ZES 1.5, BMS 0.0 (%), P=0.0025)., Conclusions: This study demonstrates a variable pattern of strut coverage in the bifurcation among stent technologies, with a high percentage of PES floating struts remaining uncovered at 6-month follow-up.

The risk of late stent thrombosis represents a major concern for patients treated with drug-eluting stents (DES). Delayed healing and incomplete stent coverage were commonly observed in pathologic specimens of vessels treated with DES. In-situ assessment of the stent coverage has been limited by the low spatial resolution of current image modalities. Optical coherence tomography (OCT) enables real-time, full tomographic, in-vivo visualization of coronary vessel microstructure. Struts coverage and vessel response of DES compared to BMS are the most immediate clinical applications of OCT. Thickness of coverage and strut apposition can be quantified at micron-scale level with a resolution 10-30 times higher than conventional intravascular ultrasound. Current clinical experience demonstrates the high level of accuracy of OCT in evaluating the heterogeneity of vascular healing following DES implantation. Neointimal coverage at strut level assessed by OCT seems a reasonable intermediate endpoint to quickly scrutinize in preregistration studies the safety profile of the next generation of DES. Major limitations of current OCT technology are shallow depth of light penetration and the need to occlude the vessel for blood removal. Second generation forms of OCT, which allow images to be recorded faster (congruent with 10 times) during a nonocclusive flush, have been recently developed. Full, quick scan of multiple and long stent without occlusion balloon is possible. Further technical advancements are expected to provide sharper images with additional contrast and tissue texture characterization. The value of these improvements must be gauged by the degree of impact in DES technology and patient care., ((c) 2008 Wiley-Liss, Inc.)