Monitoring creatine and phosphocreatine by (13)C MR spectroscopic imaging during and after (13)C4 creatine loading: a feasibility study.

Creatine (Cr) supplementation to enhance muscle performance shows variable responses among individuals and different muscles. Direct monitoring of the supplied Cr in muscles would address these differences. In this feasibility study, we introduce in vivo 3D (13)C MR spectroscopic imaging (MRSI) of the leg with oral ingestion of (13)C4-creatine to observe simultaneously Cr and phosphocreatine (PCr) for assessing Cr uptake, turnover, and the ratio PCr over total Cr (TCr) in individual muscles. (13)C MRSI was performed of five muscles in the posterior thigh in seven subjects (two males and two females of ~20 years, one 82-year-old male, and two neuromuscular patients) with a (1)H/(13)C coil in a 3T MR system before, during and after intake of 15 % (13)C4-enriched Cr. Subjects ingested 20 g Cr/day for 4 days in four 5 g doses at equal time intervals. The PCr/TCr did not vary significantly during supplementation and was similar for all subjects and investigated muscles (average 0.71 ± 0.07), except for the adductor magnus (0.64 ± 0.03). The average Cr turnover rate, assessed in male muscles, was 2.1 ± 0.7 %/day. The linear uptake rates of Cr were variable between muscles, although not significantly different. This assessment was possible in all investigated muscles of young male volunteers, but less so in muscles of the other subjects due to lower signal-to-noise ratio. Improvements for future studies are discussed. In vivo (13)C MRSI after (13)C-Cr ingestion is demonstrated for longitudinal studies of Cr uptake, turnover, and PCr/TCr ratios of individual muscles in one exam.

Quantitative muscle ultrasound versus quantitative magnetic resonance imaging in facioscapulohumeral dystrophy.

INTRODUCTION: Ultrasound and magnetic resonance imaging (MRI) are non-invasive methods that can be performed repeatedly and without discomfort. In the assessment of neuromuscular disorders it is unknown if they provide complementary information. In this study we tested this for patients with facioscapulohumeral muscular dystrophy (FSHD). METHODS: We performed quantitative muscle ultrasound (QMUS) and quantitative MRI (QMRI) of the legs in 5 men with FSHD. RESULTS: The correlation between QMUS-determined z-scores and QMRI-determined muscle fraction and T1 signal intensity (SI) was very high. QMUS had a wider dynamic range than QMRI, whereas QMRI could detect inhomogeneous distribution of pathology over the length of the muscles. CONCLUSIONS: Both QMUS and QMRI are well suited for imaging muscular dystrophy. The wider dynamic range of QMUS can be advantageous in the follow-up of advanced disease stages, whereas QMRI seems preferable in pathologies such as FSHD that affect deep muscle layers and show inhomogeneous abnormality distributions.

Determining the role of sarcomeric proteins in facioscapulohumeral muscular dystrophy: a study protocol.

BACKGROUND: Although muscle weakness is a hallmark of facioscapulohumeral muscular dystrophy (FSHD), the molecular mechanisms that lead to weakness in FSHD remain largely unknown. Recent studies suggest aberrant expression of genes involved in skeletal muscle development and sarcomere contractility, and activation of pathways involved in sarcomeric protein degradation. This study will investigate the contribution of sarcomeric protein dysfunction to the pathogenesis of muscle weakness in FSHD. METHODS/DESIGN: Evaluation of sarcomeric function using skinned single muscle fiber contractile studies and protein analysis in muscle biopsies (quadriceps femoris and tibialis anterior) from patients with FSHD and age- and gender-matched healthy controls. Patients with other forms of muscular dystrophy and inflammatory myopathy will be included as disease controls to assess whether results are due to changes specific for FSHD, or a consequence of muscle disease in general. A total of 56 participants will be included. Extensive clinical parameters will be measured using MRI, quantitative muscle studies and physical activity assessments. DISCUSSION: This study is the first to extensively investigate muscle fiber physiology in FSHD following an earlier pilot study suggesting sarcomeric dysfunction in FSHD. The results obtained in this study will increase the understanding of the pathophysiology of muscle weakness in FSHD, and possibly identify novel targets for therapeutic intervention.

Tromboendarterectomía pulmonar en hipertensión pulmonar tromboembólica crónica. Experiencia binacional Uruguay-Argentina / Pulmonary thromboendarterectomy in chronic thromboembolic pulmonary hypertension. Binational experience Uruguay-Argentina / Tromboendarterectomia pulmonar na hipertensão pulmonar tromboembólica crônica. Experiência binacional Uruguai-Argentina

Introducción: La tromboendarterectomía pulmonar (TEA) es la principal herramienta terapéutica en hipertensión pulmonar tromboembólica crónica (HPTEC), potencialmente curativa. Se analiza la experiencia de 13 años de TEAs de pacientes uruguayos en el marco del convenio con el Hospital Universitario Fundación Favaloro (HUFF-Argentina). Metodología: Estudio analítico, observacional y retrospectivo de todas las TEAs realizadas entre 2011 y 2023. Resultados: Se realizaron 15 TEAs. 46 ± 17 años, 67% hombres. Diez pacientes tenían antecedentes de enfermedad tromboembólica previa y 8 hipercoagulabilidad. El tiempo desde el inicio de los síntomas al diagnóstico fue de 36 (22-78) meses. Ochenta por ciento se encontraba en CF III, con una distancia total recorrida en la prueba de la marcha de 6 minutos de 375 (272-458) metros, severidad ecocardiográfica (TAPSE/PAPs 0,22 ± 0,08 mm/mmHg) y hemodinámica (RVP 11 ± 5 UW) que mejoraron significativamente en el posoperatorio temprano. La mortalidad intrahospitalaria fue del 20% que se mantuvo en el seguimiento de 34 (7-97) meses excepto un paciente que murió por una nueva embolia de pulmón a los 3 años. Todos los fallecidos tenían una hemodinamia preoperatoria significativamente más grave (RVP 19 ± 6 UW, índice cardíaco 1,5 ± 0,4 L/min/m2). Seis sobrevivientes (50%) presentaron HP residual asociada a una mayor PAPm y RVP preoperatorias y menor recuperación funcional y ecocardiográfica a corto plazo (P <0,05), dos de los cuales recibieron terapia específica posterior al procedimiento. Conclusiones: La TEA determinó mejoría clínica, ecocardiográfica y hemodinámica. Seis supervivientes (50%) normalizaron la hemodinamia de reposo. La severidad hemodinámica preoperatoria dado por las lesiones obstructivas y microangiopatía distales se asoció con una alta tasa de complicaciones y mortalidad perioperatorias. La reducción del retardo en el diagnóstico y tratamiento junto con una mayor tasa de TEAs/año podrían reducir las complicaciones y mejorar el pronóstico.

Summary Introduction: Pulmonary thromboendarterectomy (PTE) is the main therapeutic tool for chronic thromboembolic pulmonary hypertension (CTEPH), and is potentially curative. The experience of 13 years of PTEs on Uruguayan patients under the agreement with the University Hospital Fundación Favaloro (HUFF-Argentina) is analyzed. Methodology: Analytical, observational, and retrospective study of all PTEs performed between 2011 and 2023. Results: Fifteen PTEs were performed. Age was 46 ± 17 years, 67% male. Ten patients had a history of prior thromboembolic disease, and 8 had hypercoagulability. The time from symptom onset to diagnosis was 36 (22-78) months. Eighty percent were in NYHA Functional Class III, with a total distance walked in the 6-minute walk test of 375 (272-458) meters, echocardiographic severity (TAPSE/sPAP 0,22 ± 0,08 mm/mmHg), and hemodynamic severity (PVR 11 ± 5 WU) which significantly improved in the early postoperative period. In-hospital mortality was 20% and remained at a follow-up of 34 (7-97) months, except for one patient who died from a new pulmonary embolism at 3 years. All deceased patients had significantly more severe preoperative hemodynamics (PVR 19 ± 6 WU, cardiac index 1,5 ± 0,4 L/min/m²). Six survivors (50%) presented with residual PH associated with higher preoperative mPAP and PVR and lower short-term functional and echocardiographic recovery (P <0,05), two of whom received specific therapy post-procedure. Conclusions: PTE resulted in clinical, echocardiographic, and hemodynamic improvement. Six survivors (50%) normalized resting hemodynamics. Preoperative hemodynamic severity due to distal obstructive lesions and microangiopathy was associated with a high rate of perioperative complications and mortality. Reducing the delay in diagnosis and treatment and a higher rate of PTEs/year could reduce complications and improve prognosis.

Introdução: A tromboendarterectomia pulmonar (TEP) é a principal ferramenta terapêutica na hipertensão pulmonar tromboembólica crônica (HPTEC), potencialmente curativa. Analisa-se a experiência de 13 anos de TEPs em pacientes uruguaios no âmbito do convênio com o Hospital Universitário Fundação Favaloro (HUFF-Argentina). Metodologia: Estudo analítico, observacional e retrospectivo de todas as TEPs realizadas entre 2011 e 2023. Resultados: Foram realizadas 15 TEPs. Idade de 46 ± 17 anos, 67% homens. Dez pacientes tinham antecedentes de doença tromboembólica prévia e 8 hipercoagulabilidade. O tempo desde o início dos sintomas até o diagnóstico foi de 36 (22-78) meses. Oitenta por cento encontravam-se em Classe Funcional III, com uma distância total percorrida no teste de caminhada de 6 minutos de 375 (272-458) metros, gravidade ecocardiográfica (TAPSE/sPAP 0,22 ± 0,08 mm/mmHg) e hemodinâmica (RVP 11 ± 5 UW) que melhoraram significativamente no pós-operatório precoce. A mortalidade intra-hospitalar foi de 20% e manteve-se no seguimento de 34 (7-97) meses, exceto um paciente que faleceu por uma nova embolia pulmonar aos 3 anos. Todos os falecidos apresentavam hemodinâmica pré-operatória significativamente mais grave (RVP 19 ± 6 UW, índice cardíaco 1,5 ± 0,4 L/min/m²). Seis sobreviventes (50%) apresentaram HP residual associada a maior PAPm e RVP pré-operatórias e menor recuperação funcional e ecocardiográfica a curto prazo (P <0,05), dois dos quais receberam terapia específica pós-procedimento. Conclusões: A TEP resultou em melhora clínica, ecocardiográfica e hemodinâmica. Seis sobreviventes (50%) normalizaram a hemodinâmica de repouso. A gravidade hemodinâmica pré-operatória devido a lesões obstrutivas e microangiopatia distal foi associada a uma alta taxa de complicações e mortalidade perioperatória. A redução do atraso no diagnóstico e tratamento juntamente com uma maior taxa de TEPs/ano poderia reduzir as complicações e melhorar o prognóstico.

MRI-Guided Biopsy as a Tool for Diagnosis and Research of Muscle Disorders.

BACKGROUND: Sampling error is a common problem in muscle biopsies. MRI-guided biopsy allows verification of biopsy site during the procedure, which may reduce sampling error in patients with focal disease. OBJECTIVES: To describe the technique for MRI-guided muscle biopsy and discuss potential applications. METHODS: Axial MRI images were acquired to determine the target site for muscle biopsy. Needle trajectory was planned on 3D T1 weighted imaging and a MRI-guided biopsy of the vastus lateralis was performed in 13 FSHD patients. RESULTS: An adequate amount of muscle tissue was obtained in all participants, and MRI-guided biopsy succeeded in reaching focal target sites. However, symptomatic hematomas were observed in 2/13 patientsDiscussion:MRI-guided biopsy has a higher complication rate compared to traditional needle biopsy, most likely due to proximity to blood vessels in combination with the vacuum-assisted suction of the MRI-guided technique. We recommend that this technique is reserved for select diagnostic cases and research questions, with careful assessment of vasculature and reduced suction levels.

Quantitative MRI reveals decelerated fatty infiltration in muscles of active FSHD patients.

OBJECTIVE: To investigate the effects of aerobic exercise training (AET) and cognitive-behavioral therapy (CBT), directed towards an increase in daily physical activity, on the progression of fatty infiltration and edema in skeletal muscles of patients with facioscapulohumeral muscular dystrophy (FSHD) type 1 by T2 MRI. METHODS: Quantitative T2 MRI (qT2 MRI) and fat-suppressed T2 MRI of the thigh were performed at 3T on 31 patients, 13 of whom received usual care (UC), 9 AET, and 9 CBT. Muscle-specific fat fractions (%), derived from qT2 MRI, were recorded pretreatment and posttreatment. Intervention effects were analyzed by comparing fat fraction progression rates of the UC with the treated groups using Mann-Whitney tests, and intermuscle differences by a linear mixed model. Edematous hyperintense lesions were identified on the fat-suppressed T2 MRI. RESULTS: The intraclass correlation coefficient for reproducibility of qT2 MRI fat assessment was 0.99. In the UC group, the fat fraction increased by 6.7/year (95% confidence interval [CI] 4.3 to 9.1). This rate decreased to 2.9/year (95% CI 0.7 to 5.2) in the AET (p = 0.03) and 1.7/year (95% CI -0.2 to 3.6) in the CBT group (p = 0.00015). The treatment effect differed among individual muscles. Fewer new edematous lesions occurred after therapy. CONCLUSIONS: Fat fraction derived from qT2 MRI is a reproducible and sensitive biomarker to monitor the effects of increased physical activity in individual muscles. This biomarker reports a favorable effect of AET and CBT on the rate of muscular deterioration in FSHD as reflected in decelerated fat replacement. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for patients with FSHD type 1, both AET and CBT decrease the rate of fatty infiltration in muscles.

Evaluation of exposure-response relationships for health effects of microbial bioaerosols - A systematic review.

Studies suggest adverse health effects following exposure to bioaerosols in the environment and in particular at workplaces. However, there is still a lack of health-related exposure limits based on toxicological or epidemiological studies from environmental health or from the working environment. The aim of this study was to derive health-based exposure limits for bioaerosols that can protect the general population as group "at risk" via environmental exposure using analysis of peer-reviewed studies related to occupational medicine, indoor air and environmental health. The derivation of exposure limits should be conducted by the members of a bioaerosol expert panel according to established toxicological criteria. A systematic review was performed in Medline (PubMed) including studies containing both data on exposure measurements and observed health outcomes. In addition, literature recommended by the experts was considered. A comprehensive search strategy was generated and resulted in a total of n=1569 studies in combination with the literature recommendations. Subsequently, abstracts were screened using defined exclusion criteria yielding a final number of n=44 studies. A standardized extraction sheet was used to combine data on health effects and exposure to different bioaerosols. After full-text screening and extraction according to the defined exclusion criteria n=20 studies were selected all related to occupational exposures comprising the working areas wood processing, farming, waste processing and others. These studies were analyzed in collaboration with the bioaerosol expert network in terms of suitability for derivation of health-related exposure limits. The bioaerosol expert network concluded that none of the analyzed studies provided suitable dose-response relationships for derivation of exposure limits. The main reasons were: (1) lack of studies with valid dose-response data; (2) diversity of employed measuring methods for microorganisms and bioaerosol-emitting facilities; (3) heterogeneity of health effects; (4) insufficient exposure assessment. However, several indicator parameters and exposure concentrations could be identified for different bioaerosol-emitting facilities. Nevertheless, health-related exposure limits are urgently needed especially in approval procedures of facilities like composting plants or livestock farms emitting bioaerosols in the neighbourhood of residents. In the regulatory toxicology framework, it is common to use animal experimental studies for derivation of general exposure limits if appropriate environmental epidemiological studies on harmful substances are lacking. This might be another possibility to obtain health-related exposure limits for specific bioaerosol parameters. Furthermore, we recommend to use suitable measurable outcome parameters related to bioaerosols; to measure bioaerosols according to a protocol representative for exposure pattern and duration at the particular work place; to develop standardized detection methods for indicator parameters; to combine different detection methods to compensate for the limitations of each method; to apply new analysis methods to identify the real risk potential.

Strain de la aurícula izquierda por speckle tracking: descripción de protocolo para su medición "paso a paso"

En base a la evidencia disponible y a la experiencia de trabajo en la cohorte del estudio GEnotipo, Fenotipo y Ambiente de la HiperTensión arterial en el UruguaY (GEFA-HT-UY) se describe un protocolo "paso a paso" para la adquisición y medición de strain de la aurícula izquierda, tanto de forma global como para un análisis segmentario tipo "ojo de buey", mediante ecocardiografía bidimensional con speckle tracking.

Summary: Based on the available evidence and work experience of the GEnotipo, Fenotipo y Ambiente de la HiperTensión arterial en el UruguaY (GEFA-HT-UY) cohort, a "step by step" protocol for the acquisition and measurement of the left atrial strain is described, both as a global and segmentary analysis ("bull's eye" like ) using two-dimensional speckle tracking echocardiography.

Baseado nos elementos disponíveis e a experiência de trabalhar na coorte do estudo GEnotipo, Fenotipo y Ambiente de la HiperTensión arterial en el UruguaY (GEFA-HT-UY) se descreve um protocolo de "passo a passo" para a aquisição e a medição do strain da aurícula esquerda, tanto em forma global como pra uma análise segmentar tipo "olho de boi", usando a ecocardiografia bidimensional com speckle tracking.

Strain de la aurícula izquierda por speckle tracking: evaluación de su reproducibilidad global y segmentaria / Left atrium strain by speckle tracking: evaluation of its global and segmental reproducibility / Strain do atrio esquerdo por speckle tracking: avaliação da sua reprodutibilidade global e segmentar

Resumen: Objetivos: evaluar la reproducibilidad intra e interobservador en la medición del strain auricular izquierdo función reservorio mediante speckle tracking, usando un protocolo para su análisis global y segmentario. Métodos y resultados: se estableció un protocolo para la adquisición y medición del strain de la aurícula izquierda (SAI), para un análisis global y segmentario, utilizando un modelo tipo "ojo de buey". Se evaluó su reproducibilidad mediante el coeficiente de correlación intraclase (CCI) en 20 participantes de la cohorte GEnotipo, Fenotipo y Ambiente de la HiperTensión arterial en el UruguaY (GEFA-HT-UY). Se obtuvo una excelente reproducibilidad global intraobservador de 0,92 (IC: 0,81-0,97) y buena reproducibilidad interobservador de 0,82 (IC: 0,59-0,92). El análisis segmentario de SAI no fue reproducible. Los valores promedio de SAI fueron 31,0% (± 7,5) para la vista de 4 cámaras; 34,6% (± 9,9) para la vista de 2 cámaras, y 36,8% (± 13,9) para la vista de 3 cámaras. El valor global de SAI tomando las tres vistas fue de 34,1% (± 7,8) y de 32,8% (± 6,5) considerando las vistas de 4 y 2 cámaras. Conclusión: el protocolo de adquisición y análisis de SAI para la función de reservorio fue reproducible para su análisis global, no así para su análisis segmentario.

Summary: Objective: to evaluate intra and inter-observer reproducibility of speckle tracking left atrial strain reservoir function using a protocol for its global and segmental analysis. Methods: a protocol for acquisition and measurement of left atrial strain was created (bull's-eye type), for its global and segmental analysis. Reproducibility was assessed using intraclass correlation coefficient in twenty participants from the GEnotipo, Fenotipo y Ambiente de la HiperTensión arterial en el UruguaY cohort. For global assessment intra-observer reproducibility graded excellent (0.92 (IC: 0.81-0.97)) while inter-observer reached good reproducibility (0.82 (IC: 0.59-0.92)). Left atrial strain segmental analysis was not reproducible. Mean (±SD) left atrial strain was 31.0±7.5% for 4 chamber view, 34.6±9.9% for 2 chamber view and 36.8±13.9% for 3 chamber view. Global left atrial strain considering three views was 34.1±7.8%, and 32.8±6.5% considering 4 and 2 chamber views. Conclusion: left atrial strain acquisition and analysis protocol for reservoir function was reproducible for its global but not for its segmental analysis.

Resumo: Objetivo: avaliar a reprodutibilidade intra e interobservador do strain speckle tracking atrial esquerdo função de reservatório usando um protocolo para sua análise global e segmentar. Métodos: foi criado um protocolo de aquisição e mensuração de strain do atrio esquerdo, por sua análise global e segmentar (tipo olho de boi). A reprodutibilidade foi avaliada por meio do coeficiente de correlação intraclasse em vinte participantes da coorte GEnotipo, Fenotipo e Ambiente da Hiper-Tensiologia arterial em UruguaY. Para a avaliação global, a reprodutibilidade intra-observador foi excelente (0,92 (IC: 0,81-0,97)), enquanto o interobservador alcançou boa reprodutibilidade (0,82 (IC: 0,59-0,92)). A análise segmentar de strain do atrio esquerdo não foi reprodutível. A média (± SD) de strain do atrio esquerdo foi 31,0 ± 7,5% para 4 câmaras, 34,6 ± 9,9% para 2 câmaras e 36,8 ± 13,9% para 3 câmaras. A strain global, considerando três visualizações, foi de 34,1 ± 7,8% e 32,8 ± 6,5% considerando a visão de 4 e 2 câmaras. Conclusão: o protocolo de aquisição e análise de strain do atrio esquerdo para função de reservatório foi reproduzível para sua análise global, mas não para sua segmentação.

Prevalencia de septal pouch en una cohorte derivada para ecocardiograma transesofágico / Prevalence of septal pouch in a cohort derived for transesophageal echocardiography / Prevalência da bolsa septal em uma coorte derivada para ecocardiografia transesofágica

Resumen: Introducción: los defectos del septum interauricular (SIA) son frecuentes. En los últimos años se ha identificado una nueva entidad conocida comoseptal pouch (SP). Los datos sobre su prevalencia son escasos, estimándose entre 30%-50% en la población general. El rol como fuente de cardioembolia es discutido. Objetivos: el objetivo primario es determinar la prevalencia y caracterizar el SP; en forma secundaria, definir la variabilidad interobservador para su diagnóstico. Material y método: estudio observacional, descriptivo y analítico. Se reclutaron en forma prospectiva pacientes consecutivos derivados para ecocardiograma transesofágico (ETE) entre el 20 de abril de 2018 y el 30 de agosto de 2018. Se registraron datos patronímicos, antecedentes personales de accidente cerebrovascular (ACV), ritmo cardíaco y motivo del estudio. Se evaluó la presencia de SP y se caracterizó como left-sided septal pouch (LSSP) o rigth-sided septal pouch (RSSP); se midió profundidad, presencia de trombo en su interior y se completó el estudio ecocardiográfico. Las imágenes fueron evaluadas por dos ecocardiografistas ciegos entre sí. Las variables cualitativas se presentan en frecuencia relativa (FR); las cuantitativas en mediana e intervalo intercuartilo. Se realizó test de chi cuadrado para evaluar la asociación entre la presencia de SP y la presencia de ACV o de FA. La reproducibilidad del diagnóstico de SP fue evaluada por índice Kappa. Resultados: se incluyeron 50 sujetos. La prevalencia de SP fue de 0,5 (FR), 0,46 LSSP y 0,04 RSSP. El índice Kappa interobservador para el diagnóstico fue 0,68, error estándar 0,14, con 84% de acuerdo. Catorce sujetos tenían antecedente de ACV, en nueve de ellos se diagnosticó SP (chi cuadrado p=0,21); 18 pacientes tenían fibrilación auricular/flutter, la mitad de ellos tenía SP (chi cuadrado p=1). Conclusión: la prevalencia de SP fue de la mitad de la población, predominando ampliamente el LSSP, con buena reproducibilidad en su diagnóstico. Se trata de un hallazgo subdiagnosticado; interesa continuar investigando su posible asociación con ACV.

Summary: Introduction: the interatrial septum defects are frequent. A new entity has recently been identified, known as septal pouch. Prevalence data in general population is scarce, and is estimated between 30%-50%. The role as a source of cardioembolism is unclear. Objectives: the primary objective is to determine the prevalence and characterize the septal pouch; secondarily to define the interobserver variability for the diagnosis. Material and methods: observational, descriptive and analytical study. Consecutive patients were recruited for transesophageal echocardiography between 4/20/2018 and 8/30/2018. We recorded patronymic data, personal history of stroke, heart rate, and the reason for the study. The presence of septal pouch was defined and characterized as left-sided septal pouch or rigth-sided septal pouch; depth was measured, presence of thrombus inside and echocardiographic study measures were completed. The images were evaluated by two blind echocardiographers. The qualitative variables are presented in relative frequency (RF), the quantitative variables in median and interquartile interval. Chi square test was carried out. The reproducibility of the diagnosis of septal pouch was evaluated by Kappa index. Results: 50 subjects were included. The prevalence of septal pouch was 0.5 (RF), 0.46 left-sided septal pouch and 0.04 rigth-sided septal pouch. The interobserver Kappa index for diagnosis is 0.68, standard error 0.14, with 84% agreement. 14 subjects had stroke, in 9 of them septal pouch was diagnosed (chi square p=0.21); 18 patients had atrial fibrillation or flutter, half of them had septal pouch (chi square p=1). Conclusion: the prevalence of septal pouch was half of the population, predominantly the left-sided septal pouch, with good reproducibility in diagnosis. It is an underdiagnosed finding; further investigation is necessary to assess its relation to stroke.

Resumo: Introdução: os defeitos do septo interatrial são freqüentes. Nos últimos anos, uma nova entidade conhecida como bolsa septal foi identificada. Dados sobre prevalência são escassos, estimados em 30%-50% na população geral. O papel como fonte de cardioembolismo é discutido. Objetivos: o objetivo primário é determinar a prevalência e caracterizar a bolsa septal; secundariamente definir a variabilidade interobservador para o seu diagnóstico. Material e métodos: estudo observacional, descritivo e analítico. Consecutivos pacientes foram recrutados para ecocardiograma transesofágico entre 20/4/2018 e 30/08/2018. Registramos dados patronímicos, histórico pessoal de acidente vascular cerebral, frequência cardíaca e o motivo do estudo. A presença de bolsa septal foi definida e caracterizada como bolsa septal esquerda ou bolsa septal direita; a profundidade foi medida, a presença de trombo no interior e o estudo ecocardiográfico foram concluídos. As imagens foram avaliadas por dois ecocardiografistas cegos. As variáveis qualitativas são apresentadas em frequência relativa (FR); os quantitativos em mediana e interquartil intervalo. O teste do qui quadrado foi realizado. A reprodutibilidade do diagnóstico de bolsa septal foi avaliada pelo índice Kappa. Resultados: 50 sujeitos foram incluídos. A prevalência de bolsa septal foi de 0,5 (FR), 0,46 bolsa septal esquerda e 0,04 bolsa septal direita. O índice Kappa interobservador para diagnóstico é 0,68, erro padrão 0,14, com 84% de concordância. 14 sujeitos apresentaram acidente vascular cerebral, em 9 deles foi diagnosticada bolsa septal (qui-quadrado p=0,21); 18 pacientes apresentaram fibrilhação auricular / flutter, metade deles com bolsa septal (qui quadrado p=1). Conclusão: a prevalência de bolsa septal foi metade da população, predominantemente a bolsa septal esquerda, com boa reprodutibilidade em seu diagnóstico. É um achado subdiagnosticado; é interessante para continuar investigando sua possível associação com acidente vascular cerebral.

Cardiotoxicidad por trastuzumab en pacientes con cáncer de mama. Serie de casos / Cardiotoxicity due to trastuzumab in patients with breast cancer. Case series / Cardiotoxicidade devido ao trastuzumab em pacientes com câncer de mama. Série de casos

resumen está disponible en el texto completo

Summary: Background: trastuzumab-induced cardiac dysfunction is a manifestation of cardiotoxicity, usually reversible, transient and dose independent. Its early detection by transthoracic echocardiogram allows the modification of therapeutic schemes and the initiation of cardioprotective drugs. Objective: to evaluate the presence of trastuzumab cardiotoxicity manifested as left ventricular dysfunction assessed by transthoracic echocardiogram and its evolution with trastuzumab suspension and initiation of cardioprotective drugs. Material and methods: observational study; case series. We retrospectively selected patients who started treatment with trastuzumab for breast cancer, with at least 5 consecutive transthoracic echocardiograms and who met trastuzumab-induced cardiac dysfunction criteria defined as the relative reduction of the left ventricular ejection fraction > 10% with respect to the baseline, with final value <53%. Age, stage of the disease, cardiovascular risk factors , number of trastuzumab cycles, exposure time, left ventricular ejection fraction, reduction percentage and time to normalization were recorded. Left ventricular ejection fraction was calculated by the Simpson method. The numerical variables are expressed as median and range. Results: of a total of 43 patients at risk of trastuzumab-induced cardiac dysfunction, during the period 2014-2017, results of the eight cases that met the inclusion criteria are shown. All were asymptomatic. Baseline left ventricular ejection fraction was: 63% (55-65), at the time of trastuzumab-induced cardiac dysfunction: 49% (45-52) and percentage of decrease: 22.5% (16.1 -26.2). All the patients temporarily suspended trastuzumab and they initiated enalapril (losartan if there was intolerance) and carvedilol. Left ventricular ejection fraction normalization occurred in all patients. The time between ventricular dysfunction and normalization of left ventricular ejection fraction was 49.5 days (28-166). The ventricular dysfunction appeared early in 2 patients (cycles 5 and 6 of trastuzumab) and in the rest, between cycles 10 and 15. The patients with early manifestation had a delayed recovery of left ventricular ejection fraction (119 and 166 days respectively). After normalization of ventricular dysfunction, all patients restarted treatment with trastuzumab while maintaining cardioprotective treatment. Conclusions: in this number of cases, we observed two different patterns of trastuzumab-induced cardiac dysfunction, one with earlier manifestation and greater delay in left ventricular ejection fraction recovery. Cardiac dysfunction was reversible and all patients could continue treatment. It is the intention of the working group to continue investigating on this topic through observational cohort and randomized clinical studies to analyze the risk factors for the development of trastuzumab-induced cardiac dysfunction, as well as eventual preventive measures.

Resumo: Introdução: a disfunção ventricular devida ao trastuzumab é uma manifestação de cardiotoxicidade com lesão geralmente reversível, transitória e dose independente. Sua detecção precoce pelo ecocardiograma transtorácico permite a modificação de esquemas terapêuticos e o início de drogas cardioprotetoras. Objetivo: avaliar a presença de cardiotoxicidade do trastuzumab manifestada como disfunção do ventrículo esquerdo no ecocardiograma transtorácido e sua evolução frente à suspensão do trastuzumab e início de drogas cardioprotetoras. Material e métodos: estudo observacional; série de casos. Selecionamos retrospectivamente pacientes que iniciaram o tratamento com trastuzumab para câncer de mama, com pelo menos 5 ecocardiogramas consecutivos e que preencheram os critérios do disfunção do ventrículo esquerdo definidos como a redução relativa da fração de ejeção >10% em comparação com linha de base, com valor final: <53%. Idade, estágio da doença, fatores de risco cardiovascular , número de ciclos de trastuzumab, tempo de exposição, fração de ejeção, percentual de redução e tempo para normalização foram registrados. A fração de ejeção foi calculada pelo método de Simpson. As variáveis numéricas são expressas como mediana e intervalo. Resultados: de um total de 43 pacientes em risco de disfunção ventricular, durante o período de 2014-2017, os resultados dos oito casos que preencheram os critérios de inclusão são mostrados. Os pacientes eram assintomáticos na área cardiovascular. Linha de base de fração de ejeção: 63% (55-65), quando disfunção ventricular: 49% (45-52), e declínio percentual: 22,5% (16,1-26,2). Todos suspenderam temporariamente o trastuzumab e iniciaram o enalapril (losartan se houve intolerância) e carvedilol. A normalização da fração de ejeção ocorreu em todos os pacientes. O tempo entre o disfunção ventricular e a normalização foi de 49,5 dias (28-166). O disfunção ventricular é expressa em ciclos 5 e 6 de trastuzumab em 2 pacientes e no resto entre os ciclos 10 e 15. Os pacientes com manifestação precoce levaram mais tempo para se recuperar (119 e 166 dias, respectivamente). Após a normalização da fração de ejeção o tratamento com trastuzumab continuou mais o tratamento cardioprotetor. Conclusões: nesta série de casos, observamos dois padrões diferentes de disfunção ventricular devida ao trastuzumab, um mais precose e com mais atraso na recuperação da fração de ejeção do ventrículo esquerdo. A disfunção ventricular devida ao trastuzumab foi reversível e todos os pacientes puderam continuar o tratamento. É a intenção do grupo de trabalho para continuar investigando através de estudos de coorte observacionais e ensaios clínicos randomizados para analisar os fatores de risco para o desenvolvimento de disfunção ventricular devida ao trastuzumab e possíveis medidas preventivas.

Diez años de experiencia de un centro de referencia en hipertensión arterial pulmonar en Uruguay / A ten year experience in a pulmonary hypertension reference center in Uruguay

Introducción: la hipertensión arterial pulmonar (HAP) es una condición clínica que conduce al fallo ventricular derecho y la muerte. Se caracterizó la epidemiología de pacientes con HAP en un centro de referencia de Uruguay. Métodos: se incluyeron 52 pacientes adultos con diagnóstico invasivo de HAP (enero 2006-diciembre 2016). Se estimó el riesgo mediante un modelo de cuatro variables (clase funcional-CF, distancia recorrida de 6 minutos -DR6M, presión auricular derecha e índice cardíaco). Se le asignó un valor de 1, 2 y 3 (bajo, intermedio y alto riesgo, respectivamente) a cada variable (European Society of Cardiology y European Respiratory Society 2015). Se categorizó el riesgo mediante el redondeo al valor entero más cercano del promedio de la suma de los valores asignados para cada variable. Resultados: edad 46±2 años, 85% femenino. Predominaron la HAP idiopática, HAP asociada a cardiopatía congénita (HAP-CPC) e HAP asociada a enfermedades del tejido conectivo (HAP-ETC). Los pacientes con HAP-CPC presentaron la mayor DR6M y la menor proporción de CF III/IV (p < 0,05). La sobrevida fue menor en HAP-ETC (p = 0,069). La mortalidad al año observada fue de 0%, 6% y 20% para pacientes con bajo (n=17), intermedio (n=28) y alto (n=7) riesgo, respectivamente, independientemente de la edad, sexo y subgrupo de HAP. El 51% de los pacientes con riesgo intermedio y alto recibieron tratamiento combinado. Conclusiones: se analizaron las características y sobrevida de pacientes con HAP de un centro de referencia uruguayo. El modelo de riesgo permitió discriminar la mortalidad de los pacientes. El 51% de los pacientes con riesgo intermedio y alto recibieron tratamiento combinado.

Introduction: Pulmonary Arterial Hypertension (PAH) is a clinical condition that leads to failure in the right ventricle and death. The epidemiology of patients with pulmonary hypertension was characterized in a reference center in Uruguay. Method: 52 patients with a diagnose of invasive pulmonary hypertension (January 2006-December 2016) were included in the study. Risk was estimated by means of a four variable model (functional class -FC, functional capacity, 6 minutes walking distance -6MWD, right atrium pressure and cardiac output). Values of 1, 2 and 3 were allocated (low, medium and high risk respectively) to each variable (ESC/ERS 2015 PAH guidelines). Risk was categorized by rounding the average of the sum of values allocated for each variable to the nearest integer. Results: age ranged 46±2 years old, 85% of patients were women. Idiopathic hypertension, PAH associated to congenital heart disease (PAH-CHD) and PAH associated to connective tissue diseases (PAH-CTD) prevailed. Patients with PAH-CHD evidenced the greatest 6MWD and the lowest proportion of FC III/IV (p <0.05). Survival was lowet in the PAH-CTD (p =0.069). Mortality after one year was 0%, 6% and 20% for patients with low (n=17), intermediate (n=28) and high (n=7) risk, respectively, regardless of age, sex and subgroup of PAH. 51% of patients with intermediate and high risk received combined treatment. Conclusions: the characteristics and survival of patients with PAH of a reference center in Uruguay were analysed in the study. The risk model allowed discriminating patient mortality. 51% of patients with intermediate and high risk received combined treatment.

Introdução: a Hipertensão Arterial Pulmonar (HAP) é uma condição clínica que leva a insuficiência ventricular direita e à morte. Neste artigo descreve-se a epidemiologia dos pacientes com HAP de um centro de referência no Uruguai. Métodos: foram incluídos 52 pacientes adultos com diagnóstico invasivo de HAP (janeiro 2006-dezembro 2016). O risco foi estimado utilizando um modelo com quatro variáveis (classe funcional -CF, distância percorrida em 6 minutos -DR6M, pressão auricular direita e índice cardíaco). Foram atribuídos os valores 1, 2 ou 3 (risco baixo, médio e alto respectivamente) a cada variável (ESC/ERS 2015). O risco foi caracterizado arredondando o valor inteiro mais próximo à média da soma dos valores atribuídos a cada variável. Resultados: a média de Idade dos pacientes era 46±2 anos sendo 85% do sexo feminino. Predominaram a HAP idiopática, a HAP associada a cardiopatia congênita (HAP-CPC) e HAP associada a doenças do tecido conectivo (HAP-ETC). Os pacientes com HAP-CPC apresentaram a maior DR6M e a menor proporção de CF III/IV (p <0.05). A sobrevida foi menor nos portadores de HAP-ETC (p =0.069). A mortalidade observada ao ano foi de 0%, 6% e 20% respectivamente para pacientes com risco baixo (n=17), médio (n=28) e alto (n=7), independentemente da idade, sexo e subgrupo de HAP. 51% dos pacientes com risco médio e alto receberam tratamento combinado. Conclusões: as características e a sobrevida de pacientes com HAP de um centro de referência uruguaio foram analisadas. O modelo de risco permitiu discriminar a mortalidade dos pacientes. 51% de dos pacientes com RI/RA recibieron tratamento combinado.

Distinct disease phases in muscles of facioscapulohumeral dystrophy patients identified by MR detected fat infiltration.

Facioscapulohumeral muscular dystrophy (FSHD) is an untreatable disease, characterized by asymmetric progressive weakness of skeletal muscle with fatty infiltration. Although the main genetic defect has been uncovered, the downstream mechanisms causing FSHD are not understood. The objective of this study was to determine natural disease state and progression in muscles of FSHD patients and to establish diagnostic biomarkers by quantitative MRI of fat infiltration and phosphorylated metabolites. MRI was performed at 3T with dedicated coils on legs of 41 patients (28 men/13 women, age 34-76 years), of which eleven were re-examined after four months of usual care. Muscular fat fraction was determined with multi spin-echo and T1 weighted MRI, edema by TIRM and phosphorylated metabolites by 3D (31)P MR spectroscopic imaging. Fat fractions were compared to clinical severity, muscle force, age, edema and phosphocreatine (PCr)/ATP. Longitudinal intramuscular fat fraction variation was analyzed by linear regression. Increased intramuscular fat correlated with age (p<0.05), FSHD severity score (p<0.0001), inversely with muscle strength (p<0.0001), and also occurred sub-clinically. Muscles were nearly dichotomously divided in those with high and with low fat fraction, with only 13% having an intermediate fat fraction. The intramuscular fat fraction along the muscle's length, increased from proximal to distal. This fat gradient was the steepest for intermediate fat infiltrated muscles (0.07±0.01/cm, p<0.001). Leg muscles in this intermediate phase showed a decreased PCr/ATP (p<0.05) and the fastest increase in fatty infiltration over time (0.18±0.15/year, p<0.001), which correlated with initial edema (p<0.01), if present. Thus, in the MR assessment of fat infiltration as biomarker for diseased muscles, the intramuscular fat distribution needs to be taken into account. Our results indicate that healthy individual leg muscles become diseased by entering a progressive phase with distal fat infiltration and altered energy metabolite levels. Fat replacement then relatively rapidly spreads over the whole muscle.

29. Multimodalidad de imagen en dos casos de sarcoidosis cardíaca

Historia clínica: la sarcoidosis cardíaca presenta tres etapas fisiopatológicas (FSP): edema, infiltración y fibrosis. Las nuevas técnicas de imagen (strain longitudinal global SLG por ETT, CR y PET) permiten detectar precozmente el compromiso cardiovascular. Caso 1: 53 años, mujer, sarcoidosis sistémica en pulmón y piel en tratamiento con corticoides. Asintomática a nivel cardiovascular. ETT de control mostró afinamiento del septum basal y disquinesia a ese nivel. Se observó caída del SLG -12% con FEVI normal y a nivel del septum basal SL positivo de 1,4%. La CR en modo cine reveló iguales alteraciones sectoriales, la secuencia en T2 no mostró edema y presentó realce tardío (RT) positivo intramiocárdico inferolateral. Caso 2: 37 años, mujer, diagnóstico de sarcoidosis en piel y ganglionar; asintomática a nivel cardiovascular. El ETT mostró afinamiento con disquinesia del septum basal, FEVI normal y SLG normal pero strain disminuido (-16%) a nivel septal basal. En la CR el modo cine reveló las mismas alteraciones sectoriales en el septum basal pero sin edema en la secuencia T2 ni fibrosis en la secuencia de RT. Pruebas complementarias: Caso 1: CR secuencia RT que muestra fibrosis intramiocárdica en el sector inferolateral. Caso 2: SLG que muestra la caída del strain en el sector septum basal. Evolución clínica: nada a destacar. Diagnóstico: sarcoidosis cardíaca. Discusión: según la FSP podemos ver en etapas precoces (edema e infiltración) en el ETT un engrosamiento o adelgazamiento regional sin respetar territorio vascular siendo el sitio más frecuente el septum basal, SLG descendido y disfunción diastólica. En la CR se pueden ver alteraciones en la secuencia T2: hiperintensidad de la señal intramiocárdica de morfología nodular (edema). En las etapas tardías (fibrosis) en el ETT se observan aneurismas de la pared basal del septum y deterioro significativo de la FEVI y en la CR fibrosis con RT intramiocárdico (más frecuente en sectores basal e ínfero-lateral del VI). En el caso 1 completamos el compromiso cardíaco basados en la multimodalidad de imagen. El caso 2 presentó signos sugestivos en el ETT de compromiso cardíaco no demostrándose en la secuencia de edema ni RT, planteándonos valorar el compromiso mediante otra técnica de imagen como el PET.

59. Disfunción sistólica del ventrículo derecho: una nueva causa del fenómeno estenosis aórtica de bajo flujo-bajo gradiente paradojal

Historia clínica: Sf, 61 años. AP de: radioterapia por linfoma Hodgkin hace 40 años. Historia de disnea de esfuerzo CF III. Examen CV: RR, 72cpm, SS en foco aórtico 3/6, PA 120/80 mmHg, IY y RHY. PP: ausencia de estertores. Pruebas complementarias: ECG: RS, 75 cpm, auriculomegalia derecha, HBAI, QRS 120 ms, trastornos inespecíficos de la repolarización. ETT: EA severa calcificada con AVA 0,8 cm2 y gradiente medio 8 mmHg, índice de VS 28 ml/m2, FEVI 54%, HVI leve, relajación prolongada del VI, dilatación de cavidades derechas, disfunción sistólica severa del VD, insuficiencia tricuspídea (IT) masiva. Cateterismo cardíaco: coronarias sin estenosis, gradiente transvalvular aórtico pico a pico: 6 mmHg, GC (termodilución): 2,48 L/min e IC 1,58 L/min/m2, PAPm 20 mmHg, PCP 12 mmHg. Evolución clínica: no corresponde. Diagnóstico: el planteo diagnóstico fue de valvulopatía rádica, con IT masiva y EAo severa con bajo flujo - bajo gradiente (BF/BG) paradojal vinculada a disfunción del VD. Discusión: la estenosis aórtica de bajo flujo bajo gradiente paradojal (área valvular Ao (1,0 cm2, gradiente medio < 40 mmHg/velocidad máxima < 4,0 m/s, FEVI conservada y VS < 35 ml/m2) se explica por un bajo volumen sistólico del ventrículo izquierdo (VI) debido a fisiología restrictiva y a poscarga aumentada. Esto se asocia a características típicas del VI (HVI, tamaño reducido del VI, contractilidad disminuida no evidenciada por la FEVI y poscarga aumentada). Presentamos un caso fisiopatológicamente complejo, donde la reducción del VS es secundaria a disfunción del ventrículo derecho (VD). En este caso las características típicas asociadas a la EAo de BF/BG están ausentes, por lo que planteamos dos alternativas fisiopatológicas: la EAo es la entidad predominante y la repercusión sobre cavidades derechas es secundaria, o la cardiopatía derecha exageró la severidad de la EAo a través del bajo VS. La ausencia hipertensión pulmonar y de PCP elevada favorece la segunda hipótesis. La IT masiva podría ser primaria de origen rádico y/o secundaria a disfunción del VD de origen rádico. La importancia de identificar la causa del BF y de definir la causa de la IT es primordial para un plan terapéutico adecuado, optando en este caso por tratamiento médico, posponiendo la cirugía.

34. Cardiotoxicidad por trastuzumab en pacientes con cáncer de mama. Serie de casos

Antecedentes: la disfunción ventricular por trastuzumab (DV-TTZ) es una manifestación de cardiotoxicidad con injuria habitualmente reversible, transitoria y dosis independiente. La detección precoz de DV-TTZ mediante ETT permite la modificación de esquemas terapéuticos y el inicio de fármacos cardioprotectores. Objetivo: evaluar la presencia de cardiotoxicidad por trastuzumab (TTZ) manifestada como disfunción del VI evaluada por ETT y su evolución frente a la suspensión de TTZ e inicio de fármacos cardioprotectores. Material y método: serie de casos. Se seleccionaron retrospectivamente pacientes que iniciaron tratamiento con TTZ por cáncer de mama, con al menos 5 ETT consecutivos y que cumplieran criterios de DV-TTZ definida como la reducción de la FEVI > 10% respecto a la basal, con FEVI final < 53%. Se registraron la edad, estadio de la enfermedad, factores de riesgo CV, número de ciclos de TTZ y FEVI. Se calculó la FEVI mediante método de Simpson o estimación visual. Las variables numéricas se expresan como mediana y rango. Resultados: de un total de 43 pacientes con riesgo de DV-TTZ, 2014-2017, se muestran resultados de los ocho casos que cumplieron criterios de inclusión. Todas asintomáticas en la esfera CV. FEVI basal 62,5% (55,0-65,0), FEVI al momento de DV-TTZ 48,8% (45,0-52,0) y porcentaje de descenso -22,6% (-26,2-16,1). Todas suspendieron transitoriamente TTZ e iniciaron enalapril (losartán si hubo intolerancia) y carvedilol. La normalización de la FEVI ocurrió en 7/8 pacientes. El tiempo entre la DV-TTZ y la normalización de la FEVI fue de 50 días (28-166). La DV-TTZ se manifestó precozmente en 2 pacientes (ciclo 5 y 6 TTZ) y en el resto entre los ciclos 10 y 15. Las pacientes con manifestación precoz demoraron más en recuperar la FEVI (119 y 116 días respectivamente). Las pacientes que normalizaron la FEVI continuaron el tratamiento con TTZ manteniendo tratamiento cardioprotector. Conclusiones: en esta serie de casos observamos dos patrones diferentes de DV-TTZ, uno más precoz con mayor retardo en la recuperación de la FEVI. Es intención del grupo de trabajo continuar investigando mediante estudios observacionales de cohorte y estudios clínicos randomizados para conocer los factores de riesgo para el desarrollo de DV-TTZ, así como posibles medidas de prevención.

37. Strain auricular izquierdo por speckle tracking: protocolo para su estudio y creación de modelo para análisis segmentario

Antecedentes: el strain auricular izquierdo reservorio (SAIR) nos da información adicional respecto a la función auricular izquierda y presiones de llenado del VI. También predice eventos adversos (IC, FA). No existen publicaciones que protocolicen el método, y la evidencia disponible es dispar por diferencias en su metodología. Luego de una extensa revisión bibliográfica y en base a la experiencia de nuestro grupo de trabajo proponemos un protocolo para su estudio. Objetivo: protocolizar la medición del SAIR con Speckle Tracking. Familiarizar al ecocardiografista con esta nueva técnica. Material y método: se realizó una extensa revisión bibliográfica. Se adquirieron imágenes de ETT de pacientes de la cohorte poblacional GEFA-HT-Uy. Se realizó posproceso de las imágenes en Echopac mediante Q Analysis, utilizando Speckle Tracking. Durante un año se desarrolló la técnica realizando múltiples mediciones de Strain auricular reservorio por dos investigadores clínicos, con avanzado nivel técnico en ecocardiografía (nivel 3). Se realizaron tres medidas por paciente, normatizando la medición en base a ensayo y error. Se creó un modelo de análisis segmentario de aurícula izquierda (tipo "bull eye"). Posteriormente se confeccionó un protocolo detallado para el estudio del SAIR gatillado por onda R, el cual proponemos presentar en el Congreso Uruguayo de Cardiología. Resultados: se adquirieron imágenes de 52 pacientes, 28 mujeres. Se realizaron 156 medidas de Strain auricular, tres por paciente. Se elaboró un protocolo que estandariza la medida, gatillada por onda R. En base a este protocolo hemos estudiado la reproducibilidad de la medición del SAIR, ensayo que se presenta en forma separada. Conclusiones: se desarrolló un modelo inédito de análisis segmentario de la aurícula izquierda. Se estandariza medición del SAIR mediante Speckle Tracking. Esto permite desarrollar líneas de investigación en función auricular con este método innovador.

Mindfulness meditation associated with alterations in bottom-up processing: psychophysiological evidence for reduced reactivity.

Mental training by meditation has been related to changes in high-level cognitive functions that involve top-down processing. The aim of this study was to investigate whether the practice of meditation is also related to alterations in low-level, bottom-up processing. Therefore, intersensory facilitation (IF) effects in a group of mindfulness meditators (MM) were compared to IF effects in an age- and gender-matched control group. Smaller and even absent IF effects were found in the MM group, which suggests that changes in bottom-up processing are associated with MM. Furthermore, reduced interference of a visual warning stimulus with the IF effects was found, which suggests an improved allocation of attentional resources in mindfulness meditators, even across modalities.