121 research outputs found
The Evolution of Data Fusion Methodologies Developed to Reconstruct Coronary Artery Geometry From Intravascular Imaging and Coronary Angiography Data: A Comprehensive Review
Understanding the mechanisms that regulate atherosclerotic plaque formation and
evolution is a crucial step for developing treatment strategies that will prevent plaque
progression and reduce cardiovascular events. Advances in signal processing and the
miniaturization of medical devices have enabled the design of multimodality intravascular
imaging catheters that allow complete and detailed assessment of plaque morphology
and biology. However, a significant limitation of these novel imaging catheters is that they
provide two-dimensional (2D) visualization of the lumen and vessel wall and thus they
cannot portray vessel geometry and 3D lesion architecture. To address this limitation
computer-based methodologies and user-friendly software have been developed. These
are able to off-line process and fuse intravascular imaging data with X-ray or computed
tomography coronary angiography (CTCA) to reconstruct coronary artery anatomy. The
aim of this review article is to summarize the evolution in the field of coronary artery
modeling; we thus present the first methodologies that were developed to model vessel
geometry, highlight the modifications introduced in revised methods to overcome the
limitations of the first approaches and discuss the challenges that need to be addressed,
so these techniques can have broad application in clinical practice and research
Optical coherence tomography for the assessment of coronary atherosclerosis and vessel response after stent implantation
Optical Coherence Tomography (OCT) is a light-based imaging modality that can provide in vivo high-resolution images of the coronary artery with a level of resolution (axial 10-20 µm) ten times higher than intravascular ultrasound. The technique, uses low-coherent near infrarred light to create high-resolution cross sectional images of the vessel. The technology refinement achieved in the last years has made this imaging modality less procedurally demanding opening its possibilities for clinical use. The present thesis provides im
Advances in IVUS/OCT and Future Clinical Perspective of Novel Hybrid Catheter System in Coronary Imaging
Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) have been
developed and improved as both diagnostic and guidance tools for interventional
procedures over the past three decades. IVUS has a resolution of 100µm with a
high tissue penetration and capability of assessing the entire structure of a coronary
artery including the external elastic membrane, whereas OCT has a higher resolution of
10–20µm to assess endoluminal structures with a limited tissue penetration compared
to IVUS. Recently, two companies, CONAVI and TERUMO, integrated IVUS and OCT into
a single catheter system. With their inherent strength and limitations, the combined IVUS
and OCT probes are complementary and work synergistically to enable a comprehensive
depiction of coronary artery. In this review, we summarize the performance of the two
intracoronary imaging modalit
The Use of Intracoronary Optical Coherence Tomography in Interventional Cardiology: Safety, Feasibility and Clinical Applications
Interventional cardiology has witnessed tremendous change since 1977 when Andreas Gruentzig
successfully performed the first balloon angioplasty. Whereas initial concerns revolved around
maintaining vessel patency with issues of recoil and restenosis, the introduction of stents
changed the landscape forever. Inherent with their use, stents, and, more specifically, drugeluting
stents (DES), have become central to improved patient outcomes but, at some cost.
Catastrophic, yet fortunately still rare complications such as stent thrombosis have re-ignited an
intense need for greater scrutiny when developing and, subsequently implanting DES into our
patients.
The demand for detailed information regarding coronary artery disease has seen intravascular
imaging become pivotal at delineating atherosclerosis and tissue responses following stent
implantation. In fact, the strategy that relied on angiography alone is evolving to include better
confirmation of disease severity and stenting technique. With this, optical coherence tomography
(OCT) has grown exponentially with a broad diffusion amongst catheterisation laboratories
worldwide.
Optical coherence tomography is a procedurally demanding technique. Individual experience is
often frustrated initially with disappointing images as a result of inadequate blood clearance.
With perseverance and adequate proctorship however, one cannot help but be impressed by the
clarity and resolution afforded by this imaging modality. It is these images that have attracted
considerable attention at cardiology conferences internationally and have helped instil OCT as
the most sensitive intravascular imaging technique available today.
The aim of this thesis was to evaluate the role of OCT in contemporary coronary intervention.
Part 1 embraces the principles of the technique and the physical properties of OCT (chapter 2)
and gives an insight into where OCT is placed compared to other intravascular imaging
modalities (chapter 3). Despite the adoption of OCT in more and more catheterisation
laboratories, little has been documented as to its safety, so, in chapter 4, we review the
procedural safety of intracoronary OCT in a large group of patients across six leading European
centres
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