Optical Coherence Tomography for Online Guidance of Complex Coronary Interventions

Abstract

Decision making on lesion preparation and stent/scaffold optimization are cornerstones of patient outcome. Intravascular imaging recently emerged as a critical modality to achieve better results of stent/scaffold implantation and superior clinical outcomes compared with coronary angiography alone. Optical coherence tomography (OCT), a light-based intravascular imaging modality with high frame rate in acquisition and very high speed pullback, can interrogate the target vessel in a couple of seconds, and immediately display a pristine longitudinal lumen contour with automatic detection of lesion severity, site and lumen/stent areas. Further, OCT provides pivotal information on sites of calcium, with accurate measurements of the minimum distance from the lumen, a major determinant of stent/ scaffold underexpansion, malapposition and eccentricity. Finally, to guide the PCI procedure using OCT without operator misjudgment, a real-time point-to-point correspondence between angiographic and OCT images has been recently created. Co-registration of OCT with angiography with direct tableside control of acquisition and analysis enables the operator to plan and map optimal stent/scaffold implantation. To prove the clinical relevance of OCTguided PCI, simple, standardized interventional planning, including pre-and postprocedural automatic lumen detection metrics, has to be translated into effective treatment flow algorithms. A similar OCT algorithm is being tested in the ongoing prospective, randomized, multicenter ILUMIEN III study, to demonstrate that OCT-guided stent placement is superior to angiography-guided and non-inferior to IVUS-guided stent implantation. (Circ J 2016; 80: 2063 -2072

Early vascular responses to everolimus-eluting cobalt–chromium stent in the culprit lesions of st-elevation myocardial infarction: results from a multicenter prospective optical coherence tomography study (MECHANISM-AMI 2-week follow-up study)

“…Furthermore, the potential of FD-OCT-guided techniques were revealed. Because high-resolution FD-OCT enables the precise visualization of stent expansion, strut apposition, strut embedment, and the residual thrombus burden during the procedure [ 21 , 22 ], it may be associated with accelerated vascular healing reactions within the initial 2 weeks. However, to confirm this hypothesis, it will be necessary to perform further randomized clinical studies to compare the vascular responses after stent implantation with or without FD-OCT guidance.…”

Growth Opportunities Utilization Inter-Industry

“…The underinvestment problem is related to debt overhang (Myers, 1977). Companies with high leverage and managers who act in the interests of shareholders will reject positive NPV projects.…”

“…First, when growth opportunities are high and financial conditions are good, the optimal investment will occur. Second, when growth opportunities are low and financial conditions are poor (high leverage), debt overhang or underinvestment occurs (Myers, 1977). Third, when growth opportunities are high and financial conditions are bad (Leverage is high), risk-avoidance occurs (Brito & John, 2002).…”

“…The agency theory refers to when managers act independently from the company shareholders' interests. For example, they might reject a potential net Present Value (NPV) project as long as they benefit debtholders (Myers, 1977). As an implication, the company could lose growth opportunities (La Rocca et al, 2007).…”

Calcific Coronary Lesions

“…As light penetrates calcium OCT can measure the thickness of calcium deposition and measure the volume of calcium. Kunihiro Shimamura and colleagues [30] have shown that OCT provides pivotal information on sites of calcium, with accurate measurements of the minimum distance from the lumen, a major determinant of stent/scaffold under expansion, malapposition and eccentricity (Fig 7).…”