Publications by authors named "John Ormiston"

Aims: Percutaneous coronary intervention with Y-stenting of coronary bifurcation disease is not commonly undertaken. The procedural and medium-term clinical outcomes of coronary bifurcation lesions treated with the proximal to distal Y stent technique by a single experienced operator were reviewed.

Methods: A total of 167 consecutive procedures using either provisional Y strategies or full-coverage options performed at Auckland City Hospital, New Zealand, between January 2013 and July 2018 were included in this retrospective observational study.

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Objectives: To describe a novel technique for ostial stent placement using real-time IVUS guidance.

Background: Accurate placement of coronary stents at ostial locations is challenging with the true ostium frequently being missed increasing the risk of adverse events. We have developed a novel technique for ostial stent placement and report our benchtop testing and initial clinical experience.

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Proximal to distal Y stenting technique is a modified bifurcation technique based on the original Y stenting technique described over 20 years ago. We use a bench top model to illustrate the steps of the technique, which can provide both provisional and full coverage options, using radial artery access. This technique may be applied in clinical settings on a wide range of bifurcation anatomies with a number of unique advantages.

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Objectives: In a coronary bifurcation bench model, to determine the effects of side branch (SB) wire crossing position and balloon position on the stent scaffolding after the final proximal optimization technique (POT).

Background: POT performed as a final step after SB dilatation or kissing balloon inflation (KBI) has been widely advocated despite limited evidence.

Methods: Thirty-one stent implantations in bifurcation phantoms were performed using a one-stent provisional technique with (KBI) (n = 13), with POT-side-POT technique (n = 12) or with the two-stent culotte technique (n = 6).

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We investigated if blood flow changes induced through the presence of a stent could be detected using in vitro dynamically scaled 4D Phase-Contrast Magnetic Resonance Imaging (PC-MRI). Using idealized and patient-specific left main coronary artery bifurcations, we 3D-printed the dynamically large scaled geometries and incorporated them into a flow circuit for non-invasive acquisition with a higher effective spatial resolution. We tested the effects of using non-Newtonian and Newtonian fluids for the experiment.

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Objectives: To compare on the bench the physical and mechanical properties of Magmaris, a magnesium bioresorbable scaffold (BRS), with Absorb and DESolve polymeric BRS and a permanent metallic stent.

Background: Understanding the mechanical and physical properties of BRS is crucial for appropriate implantation and postdilatation.

Methods: Testing was performed in fluid at 37°C and in silicone bifurcation phantoms with a 30° angle between main branch (MB) and side branch.

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Background: Percutaneous coronary intervention in complex bifurcation lesions is prone to suboptimal implantation results and is associated with increased risk of subsequent clinical events. Angiographic ambiguity is high during bifurcation stenting, but it is unknown if procedural guidance by intravascular optical coherence tomography (OCT) improves clinical outcome.

Methods And Design: OCTOBER is a randomized, investigator-initiated, multicenter trial aimed to show superiority of OCT-guided stent implantation compared to standard angiographic-guided implantation in bifurcation lesions.

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Aims: This study sought to investigate the long-term clinical outcomes related to scaffold sizing based on quantitative coronary angiography.

Methods And Results: A total of 1,248 patients who received Absorb bioresorbable scaffolds in the ABSORB Cohort B, ABSORB EXTEND, and ABSORB II trials were included in the analysis. The incidence of MACE (a composite of cardiac death, any myocardial infarction [MI], and ischaemia-driven target lesion revascularisation [ID-TLR]) was analysed according to the Dmax subclassification of oversized scaffold group versus non-oversized (any undersize) scaffold group.

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Aims: The aim of this study was to evaluate the five-year clinical results of a sirolimus-eluting stent (MiStent SES) with a bioabsorbable coating designed for sustained drug delivery during and after rapid polymer dissolution.

Methods And Results: The five-year results from the DESSOLVE I and II trials including major adverse cardiac events (MACE), target lesion failure (TLF), target vessel failure (TVF), and stent thrombosis (ST) at five-year follow-up are reported. In DESSOLVE I, 10.

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Objectives: To confirm clinically that coronary balloon catheter tips may be damaged during bifurcation treatment with side-branch access through the side of a stent. On the bench, we aimed to assess the susceptibility of different balloon designs to damage. We compared catheter tip widths.

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This is a consensus document from the European Bifurcation Club concerning bench testing in coronary artery bifurcations. It is intended to provide guidelines for bench assessment of stents and other strategies in coronary bifurcation treatment where the United States Food and Drug Administration (FDA) or International Organization for Standardization (ISO) guidelines are limited or absent. These recommendations provide guidelines rather than a step-by-step manual.

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The ideal stent must fulfil a broad range of technical requirements. Stents must be securely crimped onto the delivery balloon and, in this form, must have a low profile and be sufficiently flexible to facilitate deliverability to the lesion site without distortion or displacement. Following expansion, stents must exert sufficient radial force on the vessel wall to overcome lesion resistance and elastic recoil.

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Background: Procedural technique may affect clinical outcomes after bioresorbable vascular scaffold (BVS) implantation. Prior studies suggesting such a relationship have not adjusted for baseline patient and lesion characteristics that may have influenced operator choice of technique and outcomes.

Objectives: This study sought to determine whether target lesion failure (TLF) (cardiac death, target-vessel myocardial infarction, or ischemia-driven target lesion revascularization) and scaffold thrombosis (ScT) rates within 3 years of BVS implantation are affected by operator technique (vessel size selection and pre- and post-dilation parameters).

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Objectives: The aim of this double-blind, randomized, sham-controlled study was to verify the blood pressure (BP)-lowering efficacy of externally delivered focused ultrasound for renal denervation (RDN).

Background: Nonrandomized, first proof-of-concept study and experimental evidence suggested that noninvasive techniques of RDN emerged as an alternative approach of RDN to invasive technologies.

Methods: WAVE IV, an international, randomized (1 : 1) sham-controlled, double-blind prospective clinical study, was prematurely stopped.

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Background: As the indications for transcatheter aortic valve implantation (TAVI) have expanded, so to have the demands on interventionists to allow as many patients to access this technology as possible.

Methods: We retrospectively reviewed our TAVI database for patients who had received a 29mm SAPIEN 3 valve despite having an annular area greater than the manufacturer-recommended upper limit of 683mm, as determined by multi-detector computed tomography (MDCT). Procedural and inpatient outcome data were collected.

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Background: The long-term fate of Absorb bioresorbable vascular scaffold (Abbott Vascular, Santa Clara, CA) struts jailing side branch ostia has not been clarified. We therefore evaluate serially (post-procedure and at 6 months, 1, 2, 3, and 5 years) the appearance and fate of jailed Absorb bioresorbable vascular scaffold struts.

Methods And Results: We performed 3-dimensional optical coherence tomographic analysis of the ABSORB Cohort B trial (A Clinical Evaluation of the Bioabsorbable Everolimus Eluting Coronary Stent System in the Treatment of Patients With De Novo Native Coronary Artery Lesions) up to 5 years using a novel, validated cut-plane analysis method.

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Since the first coronary angioplasty on Sept 16, 1977, the field of percutaneous coronary intervention has evolved rapidly. Now marking its 40th anniversary, percutaneous coronary intervention has become one of the most common medical procedures worldwide. Much of this progress has been due to the iteration and improvement of angioplasty technologies.

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Background: Although previous observational studies have documented late luminal enlargement and expansive remodeling following implantation of a bioresorbable vascular scaffold (BVS), no comparison with metallic stents has been conducted in a randomized fashion.

Objectives: This study sought to compare vessel remodeling patterns after either Absorb BVS or Xience metallic drug-eluting stent (DES) implantation (Abbott Vascular, Santa Clara, California) and determine the independent predictors of remodeling.

Methods: In the ABSORB II randomized trial, 383 lesions (n = 359) were investigated by intravenous ultrasound both post-procedure and at 3-year follow-up.

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Aims: Multimodality invasive imaging of the first-in-man cohort demonstrated at 5 years stable lumen dimensions and a low rate of major adverse cardiac events (MACE). However, the long-term non-invasive assessment of this device remains to be documented. The objective was to describe the 72-month multislice computed tomography (MSCT) angiographic and functional findings after the implantation of the second iteration of the fully resorbable everolimus-eluting polymeric scaffold.

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During percutaneous coronary intervention, stents are placed in narrowings of the arteries to restore normal blood flow. Despite improvements in stent design, deployment techniques and drug-eluting coatings, restenosis and stent thrombosis remain a significant problem. Population stent design based on statistical shape analysis may improve clinical outcomes.

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