500.05 Comparison Between Fractional Flow Reserve (FFR) vs. Computational Fractional Flow Reserve Derived from Three-dimensional Intravascular Ultrasound (IVUSFR) and Quantitative Flow Ratio (QFR)

BACKGROUND The determination of the ischemic status of a coronary artery by wireless physiologic assessment derived from angiography has been validated and approved in the US. However, the use ofplain angiography quantitative variables does not add much to thephysiology data since it has low correlation with fractional flowreserve (FFR) and predicts clinical outcomes poorly. Recently, a grayscale intravascular ultrasound (IVUS) derived physiology method(IVUSFR) was developed and showed a good correlation with invasiveFFR by combining the geometric advantages of IVUS with physiology.The aim of this study is to assess the coefficient of correlation (R) ofinvasive FFR compared to IVUSFR and quantitative flow ratio (QFR).METHODS Stable coronary artery disease (CAD) patients with intermediate lesions (i.e. 40?80% of diameter stenosis) were assessed by angiography and IVUS. QFR was derived from the angiography images, andIVUSFR was derived from quantitative IVUS data using computationalfluid dynamics. Coefficient of correlation (R) was used in this report.RESULTS Twenty-four patients with 34 lesions were included in theanalysis. The IVUSFR, invasive FFR, Vessel QFR fixed flow (vQFRf),and Vessel QFR contrast flow (vQFRc) values varied from 0.52 to 1.00,0.71 to 0.99, 0.55 to 1.00, and 0.34 to 1.00, respectively. The coefficient of correlation (R) of FFR vs. IVUSFR was 0.79; FFR vs. vQFRf was0.72; FFR vs. vQFRc was 0.65 (Figure).CONCLUSION Compared to invasive FFR, IVUSFR and vQFRf showed asimilar coefficient of correlation and were better than vQFR contrast flowFil: Kajita, Alexandre. Medstart; Estados UnidosFil: Bezerra, Cristiano Guedes. Universidade Federal da Bahia; BrasilFil: Ozaki, Yuichi. Medstart; Estados UnidosFil: Dan, Kazuhiro. Medstart; Estados UnidosFil: Melaku, Gebremedhin D.. Medstart; Estados UnidosFil: Pinton, Fabio A.. Universidade de Sao Paulo; BrasilFil: Falcão, Breno A. A.. Hospital of Messejana; BrasilFil: Mariani, José. Universidade de Sao Paulo; BrasilFil: Bulant, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. National Laboratory For Scientific Computing; BrasilFil: Maso Talou, Gonzalo Daniel. National Laboratory For Scientific Computing; BrasilFil: Esteves, Antonio. Universidade de Sao Paulo; BrasilFil: Blanco, Pablo Javier. National Laboratory For Scientific Computing; BrasilFil: Waksman, Ron. Medstart; Estados UnidosFil: Garcia Garcia, Hector M.. Medstart; Estados UnidosFil: Lemons, Pedro Alves. Universidade de Sao Paulo; Brasi

A Novel Algorithm to Quantify Coronary Remodeling Using Inferred Normal Dimensions

<sec><title>Background:</title><p>Vascular remodeling, the dynamic dimensional change in face of stress, can assume different directions as well as magnitudes in atherosclerotic disease. Classical measurements rely on reference to segments at a distance, risking inappropriate comparison between dislike vessel portions.</p></sec><sec><title>Objective:</title><p>to explore a new method for quantifying vessel remodeling, based on the comparison between a given target segment and its inferred normal dimensions.</p></sec><sec><title>Methods:</title><p>Geometric parameters and plaque composition were determined in 67 patients using three-vessel intravascular ultrasound with virtual histology (IVUS-VH). Coronary vessel remodeling at cross-section (n = 27.639) and lesion (n = 618) levels was assessed using classical metrics and a novel analytic algorithm based on the fractional vessel remodeling index (FVRI), which quantifies the total change in arterial wall dimensions related to the estimated normal dimension of the vessel. A prediction model was built to estimate the normal dimension of the vessel for calculation of FVRI.</p></sec><sec><title>Results:</title><p>According to the new algorithm, “Ectatic” remodeling pattern was least common, “Complete compensatory” remodeling was present in approximately half of the instances, and “Negative” and “Incomplete compensatory” remodeling types were detected in the remaining. Compared to a traditional diagnostic scheme, FVRI-based classification seemed to better discriminate plaque composition by IVUS-VH.</p></sec><sec><title>Conclusion:</title><p>Quantitative assessment of coronary remodeling using target segment dimensions offers a promising approach to evaluate the vessel response to plaque growth/regression.</p></sec

Comparison between MDCT and Grayscale IVUS in a Quantitative Analysis of Coronary Lumen in Segments with or without Atherosclerotic Plaques

Background: The diagnostic accuracy of 64-slice MDCT in comparison with IVUS has been poorly described and is mainly restricted to reports analyzing segments with documented atherosclerotic plaques. Objectives: We compared 64-slice multidetector computed tomography (MDCT) with gray scale intravascular ultrasound (IVUS) for the evaluation of coronary lumen dimensions in the context of a comprehensive analysis, including segments with absent or mild disease. Methods: The 64-slice MDCT was performed within 72 h before the IVUS imaging, which was obtained for at least one coronary, regardless of the presence of luminal stenosis at angiography. A total of 21 patients were included, with 70 imaged vessels (total length 114.6 &#177; 38.3 mm per patient). A coronary plaque was diagnosed in segments with plaque burden > 40%. Results: At patient, vessel, and segment levels, average lumen area, minimal lumen area, and minimal lumen diameter were highly correlated between IVUS and 64-slice MDCT (p < 0.01). However, 64-slice MDCT tended to underestimate the lumen size with a relatively wide dispersion of the differences. The comparison between 64-slice MDCT and IVUS lumen measurements was not substantially affected by the presence or absence of an underlying plaque. In addition, 64-slice MDCT showed good global accuracy for the detection of IVUS parameters associated with flow-limiting lesions. Conclusions: In a comprehensive, multi-territory, and whole-artery analysis, the assessment of coronary lumen by 64-slice MDCT compared with coronary IVUS showed a good overall diagnostic ability, regardless of the presence or absence of underlying atherosclerotic plaques

A Novel Algorithm to Quantify Coronary Remodeling Using Inferred Normal Dimensions

Background: Vascular remodeling, the dynamic dimensional change in face of stress, can assume different directions as well as magnitudes in atherosclerotic disease. Classical measurements rely on reference to segments at a distance, risking inappropriate comparison between dislike vessel portions. Objective: to explore a new method for quantifying vessel remodeling, based on the comparison between a given target segment and its inferred normal dimensions. Methods: Geometric parameters and plaque composition were determined in 67 patients using three-vessel intravascular ultrasound with virtual histology (IVUS-VH). Coronary vessel remodeling at cross-section (n = 27.639) and lesion (n = 618) levels was assessed using classical metrics and a novel analytic algorithm based on the fractional vessel remodeling index (FVRI), which quantifies the total change in arterial wall dimensions related to the estimated normal dimension of the vessel. A prediction model was built to estimate the normal dimension of the vessel for calculation of FVRI. Results: According to the new algorithm, “Ectatic” remodeling pattern was least common, “Complete compensatory” remodeling was present in approximately half of the instances, and “Negative” and “Incomplete compensatory” remodeling types were detected in the remaining. Compared to a traditional diagnostic scheme, FVRI-based classification seemed to better discriminate plaque composition by IVUS-VH. Conclusion: Quantitative assessment of coronary remodeling using target segment dimensions offers a promising approach to evaluate the vessel response to plaque growth/regression

TCT-72 Computational fractional flow reserve derived from three-dimensional intravascular ultrasound: a new algorithm of fusion between anatomy and physiology

BACKGROUND: Fractionalflow reserve (FFR) and intravascular ultra-sound (IVUS) imaging, respectively, are considered as the ?goldstandard? for functional and anatomical assessments of angiographicintermediate stenoses. Associating both in a single method couldoptimize diagnosis and treatment of coronary artery disease.Fil: Bezerra, Cristiano. Universidade de Sao Paulo; BrasilFil: Pinton, Fábio A.. InCor; BrasilFil: Falcão, Breno. InCor; BrasilFil: Mariani, José. Universidade de Sao Paulo; BrasilFil: Bulant, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. LNCC; BrasilFil: Talou, Gonzalo. LNCC; BrasilFil: Filh Esteves, Antonio Esteves. Hospital Sirio Libanes; BrasilFil: Blanco, Pablo. LNCC; BrasilFil: Lemos, Pedro A.. Universidade de Sao Paulo; Brasi

Assistência circulatória em choque cardiogênico pós-infarto agudo do miocárdio

Em pacientes com insuficiência coronariana aguda e choque cardiogênico, a mortalidade é alta. O dispositivo mais utilizado para suporte hemodinâmico é o balão intra-aórtico que, no entanto, pode ser insuficiente em pacientes com choque cardiogênico refratário. Relato de caso com dois dias de dor precordial opressiva e intensa, irradiada para membro superior esquerdo. ECG com supradesnivelamento anterior. Realizado angioplastia e implante de stent na artéria descendente anterior. Evolução com choque cardiogênico refratário ao uso de drogas vasoativas e balão intra-aórtico. Foram realizadas medidas hemodinâmicas e decidiu-se pela colocação do Impella® 2,5 por via percutânea para assistência circulatória

Evaluation of plaque composition by intravascular ultrasound ""virtual histology"": the impact of dense calcium on the measurement of necrotic tissue

Aims: We aimed to evaluate if the co-localisation of calcium and necrosis in intravascular ultrasound virtual histology (IVUS-VH) is due to artefact, and whether this effect can be mathematically estimated. Methods and results: We hypothesised that, in case calcium induces an artefactual coding of necrosis, any addition in calcium content would generate an artificial increment in the necrotic tissue. Stent struts were used to simulate the ""added calcium"". The change in the amount and in the spatial localisation of necrotic tissue was evaluated before and after stenting (n=17 coronary lesions) by means of a especially developed imaging software. The area of ""calcium"" increased from a median of 0.04 mm(2) at baseline to 0.76 mm(2) after stenting (p<0.01). In parallel the median necrotic content increased from 0.19 mm(2) to 0.59 mm(2) (p<0.01). The ""added"" calcium strongly predicted a proportional increase in necrosis-coded tissue in the areas surrounding the calcium-like spots (model R(2)=0.70; p<0.001). Conclusions: Artificial addition of calcium-like elements to the atherosclerotic plaque led to an increase in necrotic tissue in virtual histology that is probably artefactual. The overestimation of necrotic tissue by calcium strictly followed a linear pattern, indicating that it may be amenable to mathematical correction.State of Sao Paulo Research Foundation (FAPESP), BrazilNational Council for Scientific and Technological Development (CNPq), BrazilFAPES

Aspirin-Free Prasugrel Monotherapy Following Coronary Artery Stenting in Patients With Stable CAD: The ASET Pilot Study

Objectives: The aim of this study was to evaluate the hypothesis that prasugrel monotherapy following successful everolimus-eluting stent implantation is feasible and safe in patients with stable coronary artery disease (CAD). Background: Recent studies have suggested that short dual-antiplatelet therapy strategies may provide an adequate balance between ischemic and bleeding risks. However, the complete omission of aspirin immediately after percutaneous coronary intervention (PCI) has not been tested so far. Methods: The study was a multicenter, single-arm, open-label trial with a stopping rule based on the occurrence of definite stent thrombosis (if >3, trial enrollment would be terminated). Patients undergoing successful everolimus-eluting stent implantation for stable CAD with SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery) scores <23 were included. All participants were on standard dual-antiplatelet therapy at the time of index PCI. Aspirin was discontinued on the day of the index procedure but given prior to the procedure; prasugrel was administered in the catheterization laboratory immediately after the successful procedure, and aspirin-free prasugrel became the therapy regimen from that moment. Patients were treated solely with prasugrel for 3 months. The primary ischemic endpoint was the composite of cardiac death, spontaneous target vessel myocardial infarction, or definite stent thrombosis, and the primary bleeding endpoint was Bleeding Academic Research Consortium types 3 and 5 bleeding up to 3 months. Results: From February 22, 2018, to May 7, 2019, 201 patients were enrolled. All patients underwent PCI for stable CAD. Overall, 98.5% of patients were adherent to prasugrel at 3-month follow-up. The primary ischemic and bleeding endpoints occurred in 1 patient (0.5%). No stent thrombosis events occurred. Conclusions: Aspirin-free prasugrel monotherapy following successful everolimus-eluting stent implantation demonstrated feasibility and safety without any stent thrombosis in selected low-risk patients with stable CAD. These findings may help underpin larger randomized controlled studies to evaluate the aspirin-free strategy compared with traditional dual-antiplatelet therapy following PCI. (Acetyl Salicylic Elimination Trial: The ASET Pilot Study [ASET]; NCT03469856