Emerging Hybrid Intracoronary Imaging Technologies and Their Applications in Clinical Practice and Research.

Intravascular ultrasound and optical coherence tomography are used with increasing frequency for the care of coronary patients and in research studies. These imaging tools can identify culprit lesions in acute coronary syndromes, assess coronary stenosis severity, guide percutaneous coronary intervention (PCI), and detect vulnerable plaques and patients. However, they have significant limitations that have stimulated the development of multimodality intracoronary imaging catheters, which provide improvements in assessing vessel wall pathology and guiding PCI.

Intravascular Ultrasound and Optical Coherent Tomography Combined Catheter.

Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) are established intravascular imaging tools for evaluating plaque characteristics and volume, together with guiding percutaneous coronary interventions. The high tissue penetration of IVUS facilitates assessment of the entire vessel wall, whereas the higher resolution of OCT allows detailed assessment of endoluminal structures. A combined IVUS-OCT probe works synergistically, facilitating a greater understanding of de novo coronary artery disease and a better correlation with pathological specimens.

First in-human evaluation of a novel intravascular ultrasound and optical coherence tomography system for intracoronary imaging.

Aims: We evaluated the first in-human performance of a novel hybrid imaging catheter that permits simultaneous and co-registered acquisition of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) images.

Methods And Results: A total of 17 patients undergoing planned percutaneous coronary intervention (PCI) were imaged between August 2018 and August 2019. Eleven patients with both pre- and post-PCI IVUS and OCT images were included in the offline image analysis.

Multi-modality intravascular imaging for guiding coronary intervention and assessing coronary atheroma: the Novasight Hybrid IVUS-OCT system.

Intravascular imaging has evolved alongside interventional cardiology as an adjunctive tool for assessing plaque pathology and for guiding and optimizing percutaneous coronary intervention (PCI) in challenging lesions. The two modalities which have dominated the field are intravascular ultrasound (IVUS), which relies on sound waves and optical coherence tomography (OCT), relying on light waves. These approaches however have limited efficacy in assessing plaque morphology and vulnerability that are essential for guiding PCI in complex lesions and identifying patient at risk that will benefit from emerging therapies targeting plaque evolution.

Essential requirements for establishing and operating data trusts: practical guidance co-developed by representatives from fifteen canadian organizations and initiatives.

Introduction: Increasingly, the label "data trust" is being applied to repeatable mechanisms or approaches to sharing data in a timely, fair, safe, and equitable way. However, there is an absence of practical guidance regarding how to establish and operate a data trust.

Aim And Approach: In December 2019, the Canadian Institute for Health Information and the Vector Institute for Artificial Intelligence convened a working meeting of 19 people representing 15 Canadian organizations/initiatives involved in data sharing, most of which focus on public sector health data.

30/80 MHz Bidirectional Dual-Frequency IVUS Feasibility Evaluated In Vivo and for Stent Imaging.

Although intravascular ultrasound (IVUS) is an important tool in guiding complex coronary interventions, the resolution of existing commercial IVUS devices is considerably poorer than that of optical coherence tomography. Dual-frequency IVUS (DF IVUS), incorporating a second, higher frequency transducer, has been proposed as a possible method of overcoming this limitation. Although preliminary studies have shown that DF IVUS can produce complementary images, including large-scale morphology and high detail of superficial features, it has not yet been determined that this approach would be feasible in a more clinically relevant environment.

Cardiac Tissue-Mimicking Ballistic Gel Phantom for Ultrasound Imaging in Clinical and Research Applications.

Ballistic gel was investigated as a tissue-mimicking material in an anthropomorphic cardiac phantom for ultrasound imaging. The gel was tested for its acoustic properties and its compatibility with conventional plastics molding techniques. Speed of sound and attenuation were evaluated in the range 2-12 MHz.

Interference-free Detection of Lipid-laden Atherosclerotic Plaques by 3D Co-registration of Frequency-Domain Differential Photoacoustic and Ultrasound Radar Imaging.

As lipid composition of atherosclerotic plaques is considered to be one of the primary indicators for plaque vulnerability, a diagnostic modality that can sensitively evaluate their necrotic core is highly desirable in atherosclerosis imaging. In this regard, intravascular photoacoustic (IVPA) imaging is an emerging plaque detection modality that provides lipid-specific chemical information of arterial walls. Within the near-infrared window, a 1210-nm optical source is usually chosen for IVPA applications because lipid exhibits a strong absorption peak at that wavelength.

Frequency-domain differential photoacoustic radar: theory and validation for ultrasensitive atherosclerotic plaque imaging.

Lipid composition of atherosclerotic plaques is considered to be highly related to plaque vulnerability. Therefore, a specific diagnostic or imaging modality that can sensitively evaluate plaques' necrotic core is desirable in atherosclerosis imaging. In this regard, intravascular photoacoustic (IVPA) imaging is an emerging plaque detection technique that provides lipid-specific chemical information from an arterial wall with great optical contrast and long acoustic penetration depth.

Polycythemia Vera Presenting as Cardiac Arrest: Novel Management Strategies.

Acute coronary syndromes (ACS) usually occur in patients with multiple cardiac risk factors. In young adults, drug use and hypercoagulable states are common causes for ACS presentations. We report a case of a man in his early 30s who was diagnosed with polycythemia vera (PV) and had a cardiac arrest due to an anterolateral ST elevation myocardial infarction.

Development of a 3 French Dual-Frequency Intravascular Ultrasound Catheter.

Coronary plaque morphology, including plaque size and fibrous cap thickness, is thought to contribute to the risk of plaque rupture and future cardiac events. Dual-frequency intravascular ultrasound has been proposed as a possible technique to visualize both large-scale features and superficial detail of coronary plaque; however, it has not been found to be feasible within the constraints of a clinically functional intravascular ultrasound catheter. In this study, we describe the design and fabrication of a dual-frequency catheter using a bidirectional transducer stack with center frequencies of approximately 30 and 80 MHz.

Hybrid intravascular imaging: recent advances, technical considerations, and current applications in the study of plaque pathophysiology.

Cumulative evidence from histology-based studies demonstrate that the currently available intravascular imaging techniques have fundamental limitations that do not allow complete and detailed evaluation of plaque morphology and pathobiology, limiting the ability to accurately identify high-risk plaques. To overcome these drawbacks, new efforts are developing for data fusion methodologies and the design of hybrid, dual-probe catheters to enable accurate assessment of plaque characteristics, and reliable identification of high-risk lesions. Today several dual-probe catheters have been introduced including combined near infrared spectroscopy-intravascular ultrasound (NIRS-IVUS), that is already commercially available, IVUS-optical coherence tomography (OCT), the OCT-NIRS, the OCT-near infrared fluorescence (NIRF) molecular imaging, IVUS-NIRF, IVUS intravascular photoacoustic imaging and combined fluorescence lifetime-IVUS imaging.

In vivo feasibility of endovascular Doppler optical coherence tomography.

Feasibility of detecting intravascular flow using a catheter based endovascular optical coherence tomography (OCT) system is demonstrated in a porcine carotid model in vivo. The effects of A-line density, radial distance, signal-to-noise ratio, non-uniform rotational distortion (NURD), phase stability of the swept wavelength laser and interferometer system on Doppler shift detection limit were investigated in stationary and flow phantoms. Techniques for NURD induced phase shift artifact removal were developed by tracking the catheter sheath.

Intraoperative handheld optical coherence tomography forward-viewing probe: physical performance and preliminary animal imaging.

A prototype intraoperative hand-held optical coherence tomography (OCT) imaging probe was developed to provide micron resolution cross-sectional images of subsurface tissue during open surgery. This new ergonomic probe was designed based on electrostatically driven optical fibers, and packaged into a catheter probe in the form factor of clinically accepted Bayonet shaped neurosurgical probes. Optical properties of the probe were measured to have a ~20 μm spot size, 5 mm working distance and 4 mm field of view.

Comprehensive data visualization for high resolution endovascular carotid arterial wall imaging.

Carotid angioplasty and stenting is a minimally invasive endovascular procedure that may benefit from in vivo high resolution imaging for monitoring the physical placement of the stent and potential complications. The purpose of this pilot study was to evaluate the ability of optical coherence tomography to construct high resolution 2D and 3D images of stenting in porcine carotid artery. Four Yorkshire pigs were anaesthetized and catheterized.

Hybrid intravascular ultrasound and optical coherence tomography catheter for imaging of coronary atherosclerosis.

Objective: To demonstrate the feasibility of imaging human coronary atherosclerosis using a novel hybrid intravascular ultrasound (IVUS) and optical coherence tomography (OCT) imaging catheter.

Background: IVUS and OCT have synergistic advantages and recent studies involving both modalities suggest the use of a hybrid imaging catheter may offer improved guidance of coronary interventions and plaque characterization.

Methods: A 1.

Intravascular ultrasound results from the NEVO ResElution-I trial: a randomized, blinded comparison of sirolimus-eluting NEVO stents with paclitaxel-eluting TAXUS Liberté stents in de novo native coronary artery lesions.

Background: The NEVO sirolimus-eluting stent (NEVO SES) is a novel cobalt-chromium stent combining sirolimus release from reservoirs with bioabsorbable polymer to reduce spatial and temporal polymer exposure. The aim of this study was to assess the arterial response to the NEVO SES in a randomized, blinded comparison versus the surface-coated TAXUS Liberte paclitaxel-eluting stent (TAXUS Liberté PES) in human native coronary lesions using intravascular ultrasound (IVUS).

Methods And Results: The NEVO ResElution-I IVUS substudy enrolled 100 patients (1:1 randomization).

Right coronary wall CMR in the older asymptomatic advance cohort: positive remodeling and associations with type 2 diabetes and coronary calcium.

Background: Coronary wall cardiovascular magnetic resonance (CMR) is a promising noninvasive approach to assess subclinical atherosclerosis, but data are limited in subjects over 60 years old, who are at increased risk. The purpose of the study was to evaluate coronary wall CMR in an asymptomatic older cohort.

Results: Cross-sectional images of the proximal right coronary artery (RCA) were acquired using spiral black-blood coronary CMR (0.

Doppler optical coherence tomography for interventional cardiovascular guidance: in vivo feasibility and forward-viewing probe flow phantom demonstration.

We demonstrate the potential of a forward-looking Doppler optical coherence tomography (OCT) probe for color flow imaging in several commonly seen narrowed artery morphologies. As a proof of concept, we present imaging results of a surgically exposed thrombotic occlusion model that was imaged superficially to demonstrate that Doppler OCT can identify flow within the recanalization channels of a blocked artery. We present Doppler OCT images in which the flow is nearly antiparallel to the imaging direction.

Impaired coronary vasodilation by magnetic resonance angiography is associated with advanced coronary artery calcification.

Objectives: This study evaluated the hypothesis that impaired nitroglycerin (NTG)-induced coronary vasodilation is associated with advanced coronary atherosclerosis in asymptomatic older patients.

Background: Atherosclerosis is associated with both structural and functional abnormalities of the vessel wall. Noninvasive functional measures of subclinical coronary atherosclerosis may help characterize high-risk subjects and guide preventive therapy.

Electrostatic forward-viewing scanning probe for Doppler optical coherence tomography using a dissipative polymer catheter.

A novel flexible scanning optical probe is constructed with a finely etched optical fiber strung through a platinum coil in the lumen of a dissipative polymer. The packaged probe is 2.2 mm in diameter with a rigid length of 6mm when using a ball lens or 12 mm when scanning the fiber proximal to a gradient-index (GRIN) lens.