Radiofrequency cardiac ablation with catheters placed on opposing sides of the ventricular wall: Computer modelling comparing bipolar and unipolar modes

Purpose: The aim of this study was to compare the efficacy of bipolar (BM) vs. unipolar (UM) mode of radiofrequency ablation (RFA) in terms of creating transmural lesions across the interventricular septum (IVS) and ventricular free wall (VFW). Materials and methods: We built computational models to study the temperature distributions and lesion dimensions created by BM and UM on IVS and VFW during RFA. Two different UM types were considered: sequential (SeUM) and simultaneous (SiUM). The effect of ventricular wall thickness, catheter misalignment, epicardial fat, and presence of air in the epicardial space were also studied. Results: Regarding IVS ablation, BM created transmural and symmetrical lesions for wall thicknesses up to 15 mm. SeUM and SiUM were not able to create transmural lesions with IVS thicknesses >= 12.5 and 15 mm, respectively. Lesions were asymmetrical only with SeUM. For VFW ablation, BM also created transmural lesions for wall thicknesses up to 15 mm. However, with SeUM and SiUM transmurality was obtained for VFW thicknesses <= 7.5 and 12.5 mm, respectively. With the three modes, VFW lesions were always asymmetrical. In the scenario with air or a fat tissue layer on the epicardial side, only SiUM was capable of creating transmural lesions. Overall, BM was superior to UM in IVS and VFW ablation when the catheters were not aligned. Conclusions: Our findings suggest that BM is more effective than UM in achieving transmurality across both ventricular sites, except in the situation of the epicardial catheter tip surrounded by air or placed over a fat tissue layer.This work received financial support from the Spanish 'Plan Nacional de I+D+I del Ministerio de Ciencia e Innovacion' (TEC2011-27133-C02-01), and from the Universitat Politecnica de Valencia (PAID-06-11 Ref. 1988). A. Gonzalez-Suarez is the recipient of a Grant VaLi+D (ACIF/2011/194) from the Generalitat Valenciana, Spain. The authors alone are responsible for the content and writing of the paper.González Suárez, A.; Trujillo Guillen, M.; Koruth, J.; D'avila, A.; Berjano, E. (2014). Radiofrequency cardiac ablation with catheters placed on opposing sides of the ventricular wall: Computer modelling comparing bipolar and unipolar modes. International Journal of Hyperthermia. 30(6):372-384. https://doi.org/10.3109/02656736.2014.949878S372384306SIVAGANGABALAN, G., BARRY, M. A., HUANG, K., LU, J., POULIOPOULOS, J., THOMAS, S. P., … KOVOOR, P. (2010). Bipolar Ablation of the Interventricular Septum is More Efficient at Creating a Transmural Line than Sequential Unipolar Ablation. Pacing and Clinical Electrophysiology, 33(1), 16-26. doi:10.1111/j.1540-8159.2009.02602.xNagashima, K., Watanabe, I., Okumura, Y., Ohkubo, K., Kofune, M., Ohya, T., … Hirayama, A. (2011). Lesion Formation by Ventricular Septal Ablation With Irrigated Electrodes. Circulation Journal, 75(3), 565-570. doi:10.1253/circj.cj-10-0870D’ Avila, A., Houghtaling, C., Gutierrez, P., Vragovic, O., Ruskin, J. N., Josephson, M. E., & Reddy, V. Y. (2004). Catheter Ablation of Ventricular Epicardial Tissue. Circulation, 109(19), 2363-2369. doi:10.1161/01.cir.0000128039.87485.0bDukkipati, S. R., d’ Avila, A., Soejima, K., Bala, R., Inada, K., Singh, S., … Reddy, V. Y. (2011). Long-Term Outcomes of Combined Epicardial and Endocardial Ablation of Monomorphic Ventricular Tachycardia Related to Hypertrophic Cardiomyopathy. Circulation: Arrhythmia and Electrophysiology, 4(2), 185-194. doi:10.1161/circep.110.957290Sosa, E., Scanavacca, M., d’ Avila, A., Oliveira, F., & Ramires, J. A. F. (2000). Nonsurgical transthoracic epicardial catheter ablation to treat recurrent ventricular tachycardia occurring late after myocardial infarction. 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Lipid bodies containing oxidatively truncated lipids block antigen cross-presentation by dendritic cells in cancer

Tumor-associated dendritic cells are defective in their ability to cross-present antigens, and they accumulate lipid bodies. Here the authors show that this defect is due to an impaired trafficking of peptide-MHC class I caused by the interaction of electrophilic lipids with chaperone heat shock protein 70

Ansiedade dos estudantes diante da expectativa do exame vestibular

Este estudio investigó la ansiedad de los estudiantes en las escuelas privadas en un estado de Brasil en el examen de ingreso. La muestra fuese compuesta de 124 estudiantes de la escuela secundaria participantes del PISM (Proceso de Admisión Común), siendo 66 mujeres e 58 hombres, 69 alumnos del 1er año de escuela secundaria y 55 del 3er año. Los estudiantes respondieron a un cuestionario socio-demográfico y al Inventario de Ansiedad Rasgo-Estado (IDATE), en sus propias aulas. Hubo una diferencia significativa en relación con el género (p=0,036) que se encontró un mayor nivel de ansiedad estado en el 1er año de las mujeres en comparación con los hombres del 1er año (p = 0,004). El mismo resultado se encontró con respecto a la ansiedad-rasgo: las mujeres de 1er año son más ansiosas que los hombres del 1er año (p=0,000).O presente estudo investigou a ansiedade dos jovens estudantes de escolas particulares de um estado do Brasil em relação ao exame vestibular. A amostra foi composta por 124 estudantes do ensino médio participantes do vestibular seriado PISM (Processo de Ingresso Seletivo Misto), sendo 66 do gênero feminino e 58 do gênero masculino, 69 alunos do 1º ano do ensino médio e 55 do 3º ano. Os estudantes responderam a um questionário sócio-demográfico e ao Inventário de Ansiedade Traço-Estado (IDATE) na suas próprias salas de aula. Foi observada uma diferença significativa quanto ao gênero (p=0,036) sendo que foi encontrado um maior nível de ansiedade-estado nas mulheres do 1º ano comparativamente aos rapazes do 1ºano (p=0,004). O mesmo resultado foi encontrado com relação à ansiedade-traço: moças do 1º ano são mais ansiosas do que rapazes do 1º ano (p=0,000).This study investigated the anxiety of private schools students at the expectation of attending colleges' entrance examination in one Brazilian state. The sample consisted of 124 high school students participating in the PISM series of examination (Joint Selective Admission Process). They were 66 females and 58 males, 69 students from the 1st year and 55 from the 3rd year. Students answered a sociodemographic questionnaire and the State-Trait Anxiety Inventory in their respective classrooms. A significant difference regarding gender (p=0.036) was found, women from the 1st year presented higher levels of state-anxiety compared to men from the 1st year (p=0.004). The same result was found with respect to the trait-anxiety, women from the 1st year were more anxious than men from the 1st year (p=0.000)

2017 HRS/EHRA/ECAS/APHRS/SOLAECE expert consensus statement on catheter and surgical ablation of atrial fibrillation: executive summary.

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2017 HRS/EHRA/ECAS/APHRS/SOLAECE expert consensus statement on catheter and surgical ablation of atrial fibrillation: executive summary.

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withdrawn 2017 hrs ehra ecas aphrs solaece expert consensus statement on catheter and surgical ablation of atrial fibrillation

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Critical role of TLR2 and MyD88 for functional response of macrophages to a group IIA-Secreted phospholipase A2 from snake venom

artículo (arbitrado) -- Universidad de Costa Rica, Instituto de Investigaciones Clodomiro Picado. 2014The snake venom MT-III is a group IIA secreted phospholipase A2 (sPLA2) enzyme with functional and structural similarities with mammalian pro-inflammatory sPLA2s of the same group. Previously, we demonstrated that MT-III directly activates the innate inflammatory response of macrophages, including release of inflammatory mediators and formation of lipid droplets (LDs). However, the mechanisms coordinating these processes remain unclear. In the present study, by using TLR22/2 or MyD882/2 or C57BL/6 (WT) male mice, we report that TLR2 and MyD88 signaling have a critical role in MT-III-induced inflammatory response in macrophages. MT-III caused a marked release of PGE2, PGD2, PGJ2, IL-1b and IL-10 and increased the number of LDs in WT macrophages. In MT-III-stimulated TLR22/2 macrophages, formation of LDs and release of eicosanoids and cytokines were abrogated. In MyD882/2 macrophages, MT-III-induced release of PGE2, IL-1b and IL-10 was abrogated, but release of PGD2 and PGJ2 was maintained. In addition, COX-2 protein expression seen in MT-III-stimulated WT macrophages was abolished in both TLR22/2 and MyD882/2 cells, while perilipin 2 expression was abolished only in MyD882/2 cells. We further demonstrated a reduction of saturated, monounsaturated and polyunsaturated fatty acids and a release of the TLR2 agonists palmitic and oleic acid from MT-III-stimulated WT macrophages compared with WT control cells, thus suggesting these fatty acids as major messengers for MT-III-induced engagement of TLR2/MyD88 signaling. Collectively, our findings identify for the first time a TLR2 and MyD88-dependent mechanism that underlies group IIA sPLA2- induced inflammatory response in macrophages.This investigation was supported by research grants from FAPESP, Sao Paulo, Brazil (www.fapesp.br), grants 11/21341-5 and 10/06345-1, INCTTOX, Sao Paulo, Brazil (www.incttox.com.br), grant 573790/2008-6, CNPq PQ, Brazil (www.cnpq.br), grant 306920/2011-5, Brazil, Spanish Ministery of Science and Innovation, Spain (http://web.micinn.es/), grant BFU2010-18826.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP