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In this work we propose to validate the predictive capabilities of one-dimensional (1D) blood flow models with full three-dimensional (3D) models in the context of patient-specific coronary hemodynamics in hyperemic conditions. Such conditions mimic the state of coronary circulation during the acquisition of the Fractional Flow Reserve (FFR) index. Demonstrating that 1D models accurately reproduce FFR estimates obtained with 3D models has implications in the approach to computationally estimate FFR. To this end, a sample of 20 patients was employed from which 29 3D geometries of arterial trees were constructed, 9 obtained from coronary computed tomography angiography (CCTA) and 20 from intra-vascular ultrasound (IVUS). For each 3D arterial model, a 1D counterpart was generated. The same outflow and inlet pressure boundary conditions were applied to both (3D and 1D) models. In the 1D setting, pressure losses at stenoses and bifurcations were accounted for through specific lumped models. Comparisons between 1D models (FFR1D) and 3D models (FFR3D) were performed in terms of predicted FFR value. Compared to FFR3D, FFR1D resulted with a difference of 0.00 ± 0.03 and overall predictive capability AUC, Acc, Spe, Sen, PPV and NPV of 0.97, 0.98, 0.90, 0.99, 0.82, and 0.99, with an FFR threshold of 0.8. We conclude that inexpensive FFR1D simulations can be reliably used as a surrogate of demanding FFR3D computations.

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INTRODUÇÃO: Recentemente, o conceito dos chamados balões farmacológicos tem sido testado no tratamento da reestenose intra stent, como uma alternativa de tratamento sem implante adicional de outra camada de metal no sítio previamente tratado. Ainda que os balões farmacológicos com paclitaxel tenham se mostrado eficazes para esta finalidade, esta tecnologia ainda apresenta alguns desafios: o paclitaxel é sabidamente menos efetivo e mais tóxico que outros fármacos anti-proliferativos, em especial quando comparado ao sirolimus e seus análogos/derivados. No presente estudo avaliamos um novo balão-farmacológico (Magic Touch), que utiliza sirolimus na dose de 1,27µg/mm2 , depositado em solução excipiente (nano partícula), na concentração de 1:1. MÉTODOS: Estudo prospectivo, multicêntrico, de braço único, incluindo pacientes com reestenose tanto de stents nãofarmacológicos como farmacológicos, tratados com balão Magic Touch. Não foram incluídas reestenoses do tipo oclusiva. Os pacientes foram submetidos a avaliação angiográfica e com ultrassom (USIC) aos seis meses. O desfecho primário foi a avaliação do grau de supressão neointinamal aos seis meses pela angiografia (perda luminal) e USIC (% de obstrução luminal). RESULTADO: Um total de 17 pacientes foram incluídos, sendo a maioria do sexo masculino (59%), com média de idade de 58 anos e com 60% de diabéticos. Metade da população tratada apresentava reestenose de stents farmacológicos e em 62% dos casos a reestenose era do tipo difusa/proliferativa. Sucesso angiográfico foi obtido em 100% dos casos. Aos 6 meses, a mediana da perda luminal tardia intra stent foi de 0,21mm [0,07; 0,51] ao passo que ao USIC, o% de obstrução luminal foi de 20% [18; 24]. Do ponto de vista clínico, ocorreu apenas um óbito, de causa não cardíaca. CONCLUSÃO: Neste estudo inicial em humanos, o balão farmacológico com sirolimus e nano partículas mostrou-se eficaz em reduzir a proliferação neointimal em pacientes com reestenose prévia de stents não-farmacológicos e/ou farmacológicos. (AU)

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The goal of this work is to compare coronary hemodynamics as predicted by computational blood flow models derived from two imaging modalities: coronary computed tomography angiography (CCTA) and intravascular ultrasound integrated with angiography (IVUS). Criteria to define boundary conditions are proposed to overcome the dissimilar anatomical definition delivered by both modalities. The strategy to define boundary conditions is novel in the present context, and naturally accounts for the flow redistribution induced by the resistance of coronary vessels. Hyperemic conditions are assumed to assess model predictions under stressed hemodynamic environments similar to those encountered in Fractional Flow Reserve (FFR) calculations. As results, it was found that CCTA models predict larger pressure drops, higher average blood velocity and smaller FFR. Concerning the flow rate at distal locations in the major vessels of interest, it was found that CCTA predicted smaller flow than IVUS, which is a consequence of a larger sensitivity of CCTA models to coronary steal phenomena. Comparisons to in-vivo measurements of FFR are shown.

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This work presents a computational framework to perform a systematic and comprehensive assessment of the morphometry of coronary arteries from in vivo medical images. The methodology embraces image segmentation, arterial vessel representation, characterization and comparison, data storage, and finally analysis. Validation is performed using a sample of 48 patients. Data mining of morphometric information of several coronary arteries is presented. Results agree to medical reports in terms of basic geometric and anatomical variables. Concerning geometric descriptors, inter-artery and intra-artery correlations are studied. Data reported here can be useful for the construction and setup of blood flow models of the coronary circulation. Finally, as an application example, similarity criterion to assess vasculature likelihood based on geometric features is presented and used to test geometric similarity among sibling patients. Results indicate that likelihood, measured through geometric descriptors, is stronger between siblings compared with non-relative patients. Copyright © 2016 John Wiley & Sons, Ltd.

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Aims: The efficacy of a novel drug eluting stents with biodegradable polymer andcobalt-chromium alloy should be tested in the context of randomised trials, evenwhen using drugs known to be effective, such as sirolimus. The objective of thepresent study was to evaluate the safety and efficacy of a novel formulation of asirolimus-eluting stent with biodegradable polymer and cobalt-chromium alloyagainst a stent with the same metallic structure but without polymer coating or drugelution.Methods and results: The INSPIRON-I trial is a multicenter 2-arm randomisedtrial, conducted in 4 Brazilian institutions, which included 58 patients allocated forthe Inspiron sirolimus-eluting stent or the Cronus bare metal stent in a 2:1 ratio.Patients had de novo coronary lesions in native vessels with a diameter between2.5 and 3.5 mm, amenable for treatment with a single stent of 19 mm or less in length. The primary objective was to compare the in-stent late loss at 6 months of the sirolimus-eluting versus the control bare metal stent. Important secondary objectives included the comparison of major adverse cardiac events (MACE) ofdeath, myocardial infarction and target lesion revascularisation at 12 months. The study randomised 58 patients, 39 in the Inspiron group and 19 in the Cronusgroup. The great majority of the patients included had stable angina (76%).Baseline clinical and angiographic characteristics from both groups were similar, and 55.6% of the lesions were B2/C. The angiographic restudy at 6 months showed that percent diameter stenosis was significantly lower in the Inspiron group (15.8% vs. 38.7%, respectively; p=0.03), as well as late lumen loss (0.18 vs. 0.67 mm; p=0.009). Binary restenosis was also lower for Inspiron group, but without statistical difference (p=0.42)...

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BACKGROUND: Few studies that have assessed the effect of abbreviated oral N-acetylcysteine (NAC) regimens in radiocontrast-induced nephropathy (RCIN) yield mixed results. OBJECTIVE: To evaluate the renoprotective effect of high periprocedural oral doses (HPOD) of NAC in patients with chronic renal impairment undergoing a same-day angiography. METHODS: Sixty one patients with renal impaired function scheduled to undergo a same-day angiography were randomly assigned to NAC 1200 mg orally 3 hours before and 3 after the procedure, or a placebo. All patients received 0.9% saline intravenous. RCIN was defined as an increase in SCC > 0.5 mg/dl 48 hours after the procedure. RESULTS: The mean baseline SCC for all patients was 1.44 +/- 0.42 mg/dl. A significant difference in SCC change at 48 hours after the angiography was found (-0.07 mg/dl NAC, 0.09 mg/dl placebo, P = 0.04). RCIN occurred in 1 (3%) patient of NAC group and in 2 (7.1%) patients of placebo group (P = 0.59). Adverse effects were similar in both groups. CONCLUSIONS: In patients with mild renal impairment patients undergoing angiographic procedures, HPOD of NAC were more effective than placebo in preventing SCC change 48 hours. A non significant benefit in RCIN incidence was found.

Los escasos estudios que han evaluados los efectos de regimenes abreviados de Nacetilcisteína (NAC) oral en la nefropatía por contraste (NC) han encontrado resultados contrapuestos. OBJETIVO: Evaluar el efecto renoprotector de altas dosis orales periprocedimiento (ADOP) de NAC en pacientes con insuficiencia renal con angiografía programada el mismo día. MATERIAL y METODOS: Sesenta y un pacientes con insuficiencia renal y angiografía programada para el mismo día fueron asignados aleatoriamente a 1200 mg de NAC 3 horas previas y 3 horas posteriores al cateterismo o un placebo. Todos los pacientes recibieron hidratación endovenosa con solución salina al 0.9%. La NC se definió como el aumento en la creatinina sérica (CS) > 0.5 mg/dl a las 48 horas del procedimiento. RESULTADOS: La CS media en todos los pacientes fue 1.44: t 0.42 mg/dl. Se encontró una diferencia significativa entre ambos grupos en el cambio de CS a las 48 horas de la angiografía (-0.07 mg/dl NAC, 0.09 mg/dl placebo, P=0.04). La NC se presentó en 1 (3%) paciente del grupo NAC y en 2 (7.1 %) pacientes del grupo placebo (P=0.59). Los efectos adversos fueron similares en ambos grupos. CONCLUSION: En pacientes con insuficiencia renal leve sometidos a angiografía en el mismo día, las ADOP de NAC fueron más efectivas que el placebo en la prevención del cambio de CS a las 48 horas del procedimiento. Se encontró un beneficio no significativo en la incidencia de NC.

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BACKGROUND: Few studies that have assessed the effect of abbreviated oral N-acetylcysteine (NAC) regimens in radiocontrast-induced nephropathy (RCIN) yield mixed results. OBJECTIVE: To evaluate the renoprotective effect of high periprocedural oral doses (HPOD) of NAC in patients with chronic renal impairment undergoing a same-day angiography. METHODS: Sixty one patients with renal impaired function scheduled to undergo a same-day angiography were randomly assigned to NAC 1200 mg orally 3 hours before and 3 after the procedure, or a placebo. All patients received 0.9% saline intravenous. RCIN was defined as an increase in SCC > 0.5 mg/dl 48 hours after the procedure. RESULTS: The mean baseline SCC for all patients was 1.44 +/- 0.42 mg/dl. A significant difference in SCC change at 48 hours after the angiography was found (-0.07 mg/dl NAC, 0.09 mg/dl placebo, P = 0.04). RCIN occurred in 1 (3%) patient of NAC group and in 2 (7.1%) patients of placebo group (P = 0.59). Adverse effects were similar in both groups. CONCLUSIONS: In patients with mild renal impairment patients undergoing angiographic procedures, HPOD of NAC were more effective than placebo in preventing SCC change 48 hours. A non significant benefit in RCIN incidence was found.(AU)

Los escasos estudios que han evaluados los efectos de regimenes abreviados de Nacetilcisteína (NAC) oral en la nefropatía por contraste (NC) han encontrado resultados contrapuestos. OBJETIVO: Evaluar el efecto renoprotector de altas dosis orales periprocedimiento (ADOP) de NAC en pacientes con insuficiencia renal con angiografía programada el mismo día. MATERIAL y METODOS: Sesenta y un pacientes con insuficiencia renal y angiografía programada para el mismo día fueron asignados aleatoriamente a 1200 mg de NAC 3 horas previas y 3 horas posteriores al cateterismo o un placebo. Todos los pacientes recibieron hidratación endovenosa con solución salina al 0.9%. La NC se definió como el aumento en la creatinina sérica (CS) > 0.5 mg/dl a las 48 horas del procedimiento. RESULTADOS: La CS media en todos los pacientes fue 1.44: t 0.42 mg/dl. Se encontró una diferencia significativa entre ambos grupos en el cambio de CS a las 48 horas de la angiografía (-0.07 mg/dl NAC, 0.09 mg/dl placebo, P=0.04). La NC se presentó en 1 (3%) paciente del grupo NAC y en 2 (7.1 %) pacientes del grupo placebo (P=0.59). Los efectos adversos fueron similares en ambos grupos. CONCLUSION: En pacientes con insuficiencia renal leve sometidos a angiografía en el mismo día, las ADOP de NAC fueron más efectivas que el placebo en la prevención del cambio de CS a las 48 horas del procedimiento. Se encontró un beneficio no significativo en la incidencia de NC.(AU)

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Extrinsic compression of the left main coronary artery (LMC) by the pulmonary artery (PA) is a very unusual and poorly understood entity, usually associated with the presence of adult congenital heart disease. We identified 12 patients (age range, 6 months to 55 years) with LMC stenosis (> or = 50%) presumably secondary to compression by a dilated main PA and related to various forms of heart disease (11 congenital, 1 pulmonary hypertension). In all cases, the main PA was dilated with the main PA/aortic root diameter increased (mean, 2.0; normal value, < or = 1.0), and in all but two, PA pressures were increased (> 30 mm Hg systolic). Left coronary trunk stenosis was usually visualized in only one angiographic view (best seen in 45 degrees left anterior oblique, 30 degrees cranial projection). The LMC also appeared to be inferiorly displaced and in close contact with the left aortic sinus (mean angle between sinus and LMC was 23 degrees +/- 13 degrees, a control group was 70 degrees +/- 15 degrees ). In one patient, surgical correction of the dilated PA was associated with a reduction in LMC stenosis from 85% to < 50% and less inferior left main displacement (from 25 degrees to 50 degrees ). Patients with a dilated main PA may exhibit extrinsic LMC compression leading to significant eccentric narrowing and downward displacement of the LMC. In the presence of significant dilatation of the main PA from any etiology, functional and/or anatomic studies should be performed to exclude significant LM obstruction.

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