Vascular Deformation Mapping of Abdominal Aortic Aneurysm.

Abdominal aortic aneurysm (AAA) is a complex disease that requires regular imaging surveillance to monitor for aneurysm stability. Current imaging surveillance techniques use maximum diameter, often assessed by computed tomography angiography (CTA), to assess risk of rupture and determine candidacy for operative repair. However, maximum diameter measurements can be variable, do not reliably predict rupture risk and future AAA growth, and may be an oversimplification of complex AAA anatomy. Vascular deformation mapping (VDM) is a recently described technique that uses deformable image registration to quantify three-dimensional changes in aortic wall geometry, which has been previously used to quantify three-dimensional (3D) growth in thoracic aortic aneurysms, but the feasibility of the VDM technique for measuring 3D growth in AAA has not yet been studied. Seven patients with infra-renal AAAs were identified and VDM was used to identify three-dimensional maps of AAA growth. In the present study, we demonstrate that VDM is able to successfully identify and quantify 3D growth (and the lack thereof) in AAAs that is not apparent from maximum diameter. Furthermore, VDM can be used to quantify growth of the excluded aneurysm sac after endovascular aneurysm repair (EVAR). VDM may be a useful adjunct for surgical planning and appears to be a sensitive modality for detecting regional growth of AAAs.

Haemodynamic assessment of bicuspid aortic valve aortopathy: a systematic review of the current literature.

Both genetic and haemodynamic theories explain the aetiology, progression and optimal management of bicuspid aortic valve aortopathy. In recent years, the haemodynamic theory has been explored with the help of magnetic resonance imaging and computational fluid dynamics. The objective of this review was to summarize the findings of these investigations with focus on the blood flow pattern and associated variables, including flow eccentricity, helicity, flow displacement, cusp opening angle, systolic flow angle, wall shear stress (WSS) and oscillatory shear index. A structured literature review was performed from January 1990 to January 2018 and revealed the following 3 main findings: (i) the bicuspid aortic valve is associated with flow eccentricity and helicity in the ascending aorta compared to healthy and diseased tricuspid aortic valve, (ii) flow displacement is easier to obtain than WSS and has been shown to correlate with valve morphology and type of aortopathy and (iii) the stenotic bicuspid aortic valve is associated with elevated WSS along the greater curvature of the ascending aorta, where aortic dilatation and aortic wall thinning are commonly found. We conclude that new haemodynamic variables should complement ascending aorta diameter as an indicator for disease progression and the type and timing of intervention. WSS describes the force that blood flow exerts on the vessel wall as a function of viscosity and geometry of the vessel, making it a potentially more reliable marker of disease progression.

Evaluation of 4D flow MRI-based non-invasive pressure assessment in aortic coarctations.

Severity of aortic coarctation (CoA) is currently assessed by estimating trans-coarctation pressure drops through cardiac catheterization or echocardiography. In principle, more detailed information could be obtained non-invasively based on space- and time-resolved magnetic resonance imaging (4D flow) data. Yet the limitations of this imaging technique require testing the accuracy of 4D flow-derived hemodynamic quantities against other methodologies. With the objective of assessing the feasibility and accuracy of this non-invasive method to support the clinical diagnosis of CoA, we developed an algorithm (4DF-FEPPE) to obtain relative pressure distributions from 4D flow data by solving the Poisson pressure equation. 4DF-FEPPE was tested against results from a patient-specific fluid-structure interaction (FSI) simulation, whose patient-specific boundary conditions were prescribed based on 4D flow data. Since numerical simulations provide noise-free pressure fields on fine spatial and temporal scales, our analysis allowed to assess the uncertainties related to 4D flow noise and limited resolution. 4DF-FEPPE and FSI results were compared on a series of cross-sections along the aorta. Bland-Altman analysis revealed very good agreement between the two methodologies in terms of instantaneous data at peak systole, end-diastole and time-averaged values: biases (means of differences) were +0.4 mmHg, -1.1 mmHg and +0.6 mmHg, respectively. Limits of agreement (2 SD) were ±0.978 mmHg, ±1.06 mmHg and ±1.97 mmHg, respectively. Peak-to-peak and maximum trans-coarctation pressure drops obtained with 4DF-FEPPE differed from FSI results by 0.75 mmHg and -1.34 mmHg respectively. The present study considers important validation aspects of non-invasive pressure difference estimation based on 4D flow MRI, showing the potential of this technology to be more broadly applied to the clinical practice.

Patient-specific modeling of right coronary circulation vulnerability post-liver transplant in Alagille's syndrome.

OBJECTIVES: Cardiac output (CO) response to dobutamine can identify Alagille's syndrome (ALGS) patients at higher risk of cardiovascular complications during liver transplantation. We propose a novel patient-specific computational methodology to estimate the coronary autoregulatory responses during different hemodynamic conditions, including those experienced in a post-reperfusion syndrome (PRS), to aid cardiac risk-assessment. MATERIAL AND METHODS: Data (pressure, flow, strain and ventricular volumes) from a 6-year-old ALGS patient undergoing catheter/dobutamine stress MRI (DSMRI) were used to parameterize a closed-loop coupled-multidomain (3D-0D) approach consisting of image-derived vascular models of pulmonary and systemic circulations and a series of 0D-lumped parameter networks (LPN) of the heart chambers and the distal arterial and venous circulations. A coronary microcirculation control model (CMCM) was designed to adjust the coronary resistance to match coronary blood flow (and thus oxygen delivery) with MVO2 requirements during Rest, Stress and a virtual PRS condition. RESULTS: In all three simulated conditions, diastolic dominated right coronary artery (RCA) flow was observed, due to high right ventricle (RV) afterload. Despite a measured 45% increase in CO, impaired coronary flow reserve (CFR) (~1.4) at Stress was estimated by the CMCM. During modeled PRS, a marked vasodilatory response was insufficient to match RV myocardial oxygen requirements. Such exhaustion of the RCA autoregulatory response was not anticipated by the DSMRI study. CONCLUSION: Impaired CFR undetected by DSMRI resulted in predicted myocardial ischemia in a computational model of PRS. This computational framework may identify ALGS patients at higher risk of complications during liver transplantation due to impaired coronary microvascular responses.

Improved coronary magnetic resonance angiography using gadobenate dimeglumine in pediatric congenital heart disease.

BACKGROUND: CMRA in pediatrics remains challenging due to the smaller vessel size, high heart rates (HR), potential image degradation caused by limited patient cooperation and long acquisition times. High-relaxivity contrast agents have been shown to improve coronary imaging in adults, but limited data is available in children. We sought to investigate whether gadobenate dimeglumine (Gd-BOPTA) together with self-navigated inversion-prepared coronary magnetic resonance angiography (CMRA) sequence design improves coronary image quality in pediatric patients. METHODS: Forty consecutive patients (mean age 6±2.8years; 73% males) were prospectively recruited for a 1.5-T MRI study under general anesthesia. Two electrocardiographic-triggered free breathing steady-state free precession (SSFP) angiography sequences (A and B) with isotropic spatial resolution (1.3mm3) were acquired using a recently developed image-based self-navigation technique. Sequence A was acquired prior to contrast administration using T2 magnetization preparation (T2prep). Sequence B was acquired 5-8min after a bolus of Gd-BOPTA with the T2prep replaced by an inversion recovery (IR) pulse to null the signal from the myocardium. Scan time, signal-to noise and contrast-to-noise ratios (SNR and CNR), vessel wall sharpness (VWS) and qualitative visual score for each sequence were compared. RESULTS: Scan time was similar for both sequences (5.3±1.8 vs 5.2±1.5min, p=.532) and average heart rate (78±14.7 vs 78±14.5bpm, p=.443) remained constant throughout both acquisitions. Sequence B resulted in higher SNR (12.6±4.4 vs 31.1±7.4, p<.001) and CNR (9.0±1.8 vs 13.5±3.7, p<.001) and provided improved coronary visualization in all coronary territories (VWS A=0.53±0.07 vs B=0.56±0.07, p=.001; and visual scoring A=3.8±0.59 vs B=4.1±0.53, p<.001). The number of non-diagnostic coronary segments was lower for sequence B [A=42 (13.1%) segments vs B=33 (10.3%) segments; p=.002], and contrary to the pre-contrast sequence, never involved a proximal segment. These results were independent of the patients' age, body surface area and HR. CONCLUSIONS: The use of Gd-BOPTA with a 3D IR SSFP CMRA sequence results in improved coronary visualization in small infants and young children with high HR within a clinically acceptable scan time.

Competencia para el cuidado y soporte social percibido en cuidadores de personas con enfermedad cerebrovascular / Competence for care and perceived social support in caregivers of people with cerebrovascular disease

Resumen Las enfermedades cerebrovasculares son una de las principales causas de mortalidad, morbilidad y discapacidad en el mundo según la Organización Mundial de la Salud, al igual que para América Latina y Colombia, generando una gran carga de tipo económica y social para los sistemas de salud, para las personas y familias que lo padecen, los cuales no se encuentran preparados para la atención de este fenómeno. Objetivo Determinar la relación entre soporte social percibido y competencia para el cuidado en el hogar de cuidadores familiares de personas con enfermedad cerebrovascular. Diseño Estudio descriptivo con abordaje cuantitativo y correlacional. La población estuvo constituida por los cuidadores familiares de personas con enfermedad cerebrovascular internados en el Hospital Universitario San José de Popayán. Se utilizó la ficha de caracterización de la diada cuidador-persona con enfermedad crónica GCPC-UN-D1, el cuestionario MOS de apoyo social percibido y la escala de competencia para el cuidado en el hogar. Se realizó análisis descriptivo de las características de la población de estudio, para determinar la correlación entre variables, se acudió al coeficiente de correlación estadístico de Spearman. Resultados Predominan cuidadores del género femenino, con niveles medios de escolaridad. Se evidencia relación estadísticamente significativa entre la competencia para el cuidado en el hogar y el soporte social percibido. Conclusiones Se requiere consolidar intervenciones de soporte social y competencia para el cuidado que disminuyan la carga para el cuidado en los cuidadores familiares.

Abstract Chronic diseases are the main cause of mortality, morbidity and disability in the world according to the World Health Organization, as well as for Latin America and Colombia, generating a great economic and social burden for health systems, for people and families that suffer from it, which are not prepared for the attention of this phenomenon. Objective To determine the relationship between perceived social support and competence for care in the home of family caregivers of people with cerebrovascular disease. Design Descriptive study with quantitative and correlational approach. Population The eligible population is constituted by the family caregivers of people with cerebrovascular disease admitted to the San José de Popayán University Hospital. Collection of information It will be carried out through the approach of family caregivers of people with cerebrovascular disease hospitalized in the San José de Popayán. Instruments Characterization sheet of the caregiver dyad-person with chronic disease GCPC-UN-D1, MOS questionnaire of perceived social support, Competence for home care. A descriptive analysis of the characteristics of the study population will be carried out, in order to determine the correlation between variables, the Spearman statistical correlation coefficient was to used. Results Female caregivers predominate, with average levels of schooling. There is a statistically significant relationship between the competence for home care and the perceived social support. Conclusions It is necessary to consolidate interventions of social support and competence for care that reduce the burden for the care of family caregivers.

Relación entre los niveles de glucosa en sangre y fuerza máxima en una muestra de estudiantes universitarios / Relationship between blood glucose levels and maximum strength in a sample of university students

Introducción: Uno de los marcadores de salud metabólica que más asociación presenta con los niveles de fuerza máxima (FM) de una persona son los niveles de glucosa (GL). A pesar de esto, en población universitaria colombiana no se han desarrollado estudios que establecer la relación entre estas variables. Métodos: Durante el segundo semestre del año 2019 y el primer semestre del año 2020, se desarrolló un estudio descriptivo y transversal, en 139 estudiantes del programa de entrenamiento deportivo de la fundación universitaria del área andina (101 hombres y 38 mujeres) ubicada en Bogotá, Colombia. La GL en sangre fue evaluada con el equipo ACCUTREND, mediante la aplicación de una muestra capilar en condiciones de ayuno. La FM fue evaluada aplicando un protocolo directo para la medición de una repetición máxima (1RM) en 6 ejercicios diferentes: sentadilla completa en banco Smith, press pecho libre, extensión de rodilla en máquina, press militar libre sentado, prensa inclinada y jalón al pecho en máquina. Resultados: Los hombres presentaron un mejor rendimiento en los protocolos de 1 RM en comparación con las mujeres (P<0.05) mientras que en los niveles de GL no hubo diferencias (P>0.05). En el total de las muestras, los participantes con menor desempeño en las variables de índice general de fuerza e índice general de fuerza ajustada (Q1) presentaron mayores niveles de GL en sangre en comparación con los de mejor desempeño (Q4) (P<0.05). Discusión y Conclusiones: Los resultados de esta investigación pueden ser de gran utilidad para los profesionales en el campo del entrenamiento deportivo ya que en contextos universitarios en los que no se puedan aplicar pruebas sanguíneas que permitan identificar la salud metabólica de sus estudiantes, la medición de la FM es un alternativa viable y práctica, para de forma indirecta, identificar los alumnos con una posible alteración metabólicas. (AU)

Introduction: One of the metabolic health markers that is most associated with a person’s maximum strength (FM) levels are glucose (GL) levels. Despite this, no studies have been developed in the Colombian university population to establish the relationship between these variables. Methods: During the second semester of 2019 and the first semester of 2020, a descriptive and cross-sectional study was developed, in 139 students of the sports training program of the university foundation of the Andean area (101 men and 38 women) located in Bogotá, Colombia. GL in blood was evaluated with the ACCUTREND equipment, by applying a capillary sample under fasting conditions. The FM was evaluated by applying a direct protocol for the measurement of a maximum repetition (1RM) in 6 different exercises: full squat on Smith bench, free chest press, knee extension on machine, seated free military press, incline press and chest pull on machine. Results: Men presented better performance in the 1 RM protocols compared to women (P <0.05), while there were no differences in GL levels (P> 0.05). In the total of the samples, the participants with lower performance in the variables of general index of strength and general index of adjusted strength (Q1) presented higher levels of GL in blood compared to those with better performance (Q4) (P <0.05). Discussion and Conclusions: The results of this research can be very useful for professionals in the field of sports training since in university contexts in which blood tests that allow identifying the metabolic health of their students cannot be applied, the measurement of FM is a viable and practical alternative to indirectly identify students with a possible metabolic disorder. (AU)

Discrepancias en el agrupamiento del sistema de grupos sanguíneos ABO / Discrepancies in the grouping of ABO blood group system

La Medicina Transfusional ha logrado tan importantes avances en las últimas décadas, y se la ha reconocido como una especialidad multidisciplinaria, dirigida a la obtención y selección de los componentes de la sangre. Ha representado un avance de múltiples enfermedades, que en otros tiempos eran fatales para la vida humana. La posibilidad de esta acción terapéutica ha adquirido cada vez más seguridad, pese a los riesgos que siempre acarrea. La transfusión de componentes de la sangre establece como condición básica e imprescindible la compatibilidad ABO y RH entre donante y receptor . Se presentan tres casos de pacientes en edades escolares con procesos malignos en recidiva, politransfundidos con la pertenencia a un grupo sanguíneo y muestran un debilitamiento de los antígenos y anticuerpos, dando como resultado otro grupo sanguíneo, que al hacer remisión de su enfermedad vuelven a su grupo sanguíneo, hecho que no ocurre con frecuencia pero está descrito en la literatura.

Transfusional Medicine has achieved important advances in recent decades, and it has been recognized as a multidisciplinary field; which is aimed at obtaining and selecting blood components. It has represented a progress for the detection of multiple diseases that were fatal to human life in other precedent times. The possibility of this therapeutic action has become increasingly safe, despite the presupposed risks. The transfusion of blood components establishes as basic and indispensable condition ABO and Rh compatibility between donor and recipient. Three cases of school-aged patients are presented with relapsed malignancies, poly-transfused patients belonging to a determined blood group show a declining of antigens and antibodies resulting in another blood group, and during the remission of the disease they go back to their own blood group, this is fact that not often occurs, but it is described by the medical literature.