Os autores agradecem a Sra. Maggie Wallner (Atritech Inc. / Boston Scientific) para a revisão crítica do artigo. Os autores gostariam de agradecer ao Sr. Mahesh Deshpanade (Boston Scientific) para seu apoio administrativo e permissões de direitos autorais de organização. O vídeo foi apoiada por uma concessão irrestrita de Boston Scientific.

<ol>
	<li>Miyasaka, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Time+trends+of+ischemic+stroke+incidence+and+mortality+in+patients+diagnosed+with+first+atrial+fibrillation+in+1980+to+2000:+report+of+a+community-based+study.">Time trends of ischemic stroke incidence and mortality in patients diagnosed with first atrial fibrillation in 1980 to 2000: report of a community-based study.</a> Stroke. 36, 2362-2366 (2005).</li><li>Holmes, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Percutaneous+closure+of+the+left+atrial+appendage+versus+warfarin+therapy+for+prevention+of+stroke+in+patients+with+atrial+fibrillation:+a+randomised+non-inferiority+trial.">Percutaneous closure of the left atrial appendage versus warfarin therapy for prevention of stroke in patients with atrial fibrillation: a randomised non-inferiority trial.</a> Lancet. 374, 534-542 (2009).</li><li>Schweizer, P. A., Becker, R., Katus, H. A., Thomas, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dronedarone:+current+evidence+for+its+safety+and+efficacy+in+the+management+of+atrial+fibrillation.">Dronedarone: current evidence for its safety and efficacy in the management of atrial fibrillation.</a> Drug. 5, 27-39 (2011).</li><li>Wyse, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+rate+control+and+rhythm+control+in+patients+with+atrial+fibrillation.">A comparison of rate control and rhythm control in patients with atrial fibrillation.</a> N. Engl. J. Med. 347, 1825-1833 (2002).</li><li>Carlsson, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Randomized+trial+of+rate-control+versus+rhythm-control+in+persistent+atrial+fibrillation:+the+Strategies+of+Treatment+of+Atrial+Fibrillation+(STAF)+study.">Randomized trial of rate-control versus rhythm-control in persistent atrial fibrillation: the Strategies of Treatment of Atrial Fibrillation (STAF) study.</a> J. Am. Coll. Cardiol. 41, 1690-1696 (2003).</li><li>Van Gelder, I. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+rate+control+and+rhythm+control+in+patients+with+recurrent+persistent+atrial+fibrillation.">A comparison of rate control and rhythm control in patients with recurrent persistent atrial fibrillation.</a> N. Engl. J. Med. 347, 1834-1840 (2002).</li><li>Echt, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mortality+and+morbidity+in+patients+receiving+encainide,+flecainide,+or+placebo.+The+Cardiac+Arrhythmia+Suppression+Trial.">Mortality and morbidity in patients receiving encainide, flecainide, or placebo. The Cardiac Arrhythmia Suppression Trial.</a> N. Engl. J. Med. 324, 781-788 (1991).</li><li>Ames, A., Stevenson, W. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiology+patient+page.+Catheter+ablation+of+atrial+fibrillation.">Cardiology patient page. Catheter ablation of atrial fibrillation.</a> Circulation. 113, e666-e668 (2006).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stroke+Prevention+in+Atrial+Fibrillation+Study.+Final+results.">Stroke Prevention in Atrial Fibrillation Study. Final results.</a> Circulation. 84, 527-539 (1991).</li><li>Singer, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antithrombotic+therapy+in+atrial+fibrillation:+American+College+of+Chest+Physicians+Evidence-Based+Clinical+Practice+Guidelines+(8th+Edition).">Antithrombotic therapy in atrial fibrillation: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition).</a> Chest. 133, 546S-592S (2008).</li><li>Connolly, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dabigatran+versus+warfarin+in+patients+with+atrial+fibrillation.">Dabigatran versus warfarin in patients with atrial fibrillation.</a> N. Engl. J. Med. 361, 1139-1151 (2009).</li><li>Patel, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rivaroxaban+versus+warfarin+in+nonvalvular+atrial+fibrillation.">Rivaroxaban versus warfarin in nonvalvular atrial fibrillation.</a> N. Engl. J. Med. 365, 883-891 (2011).</li><li>Albers, G. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ximelagatran+vs+warfarin+for+stroke+prevention+in+patients+with+nonvalvular+atrial+fibrillation:+a+randomized+trial.">Ximelagatran vs warfarin for stroke prevention in patients with nonvalvular atrial fibrillation: a randomized trial.</a> JAMA. 293, 690-698 (2005).</li><li>Fiessinger, J. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ximelagatran+vs+low-molecular-weight+heparin+and+warfarin+for+the+treatment+of+deep+vein+thrombosis:+a+randomized+trial.">Ximelagatran vs low-molecular-weight heparin and warfarin for the treatment of deep vein thrombosis: a randomized trial.</a> JAMA. 293, 681-689 (2005).</li><li>Schulman, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dabigatran+versus+warfarin+in+the+treatment+of+acute+venous+thromboembolism.">Dabigatran versus warfarin in the treatment of acute venous thromboembolism.</a> N. Engl. J. Med. 361, 2342-2352 (2009).</li><li>Sick, P. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Initial+worldwide+experience+with+the+WATCHMAN+left+atrial+appendage+system+for+stroke+prevention+in+atrial+fibrillation.">Initial worldwide experience with the WATCHMAN left atrial appendage system for stroke prevention in atrial fibrillation.</a> J. Am. Coll. Cardiol. 49, 1490-1495 (2007).</li><li>Reddy, V. Y., Holmes, D., Doshi, S. K., Neuzil, P., Kar, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Safety+of+percutaneous+left+atrial+appendage+closure:+results+from+the+Watchman+Left+Atrial+Appendage+System+for+Embolic+Protection+in+Patients+with+AF+(PROTECT+AF)+clinical+trial+and+the+Continued+Access+Registry.">Safety of percutaneous left atrial appendage closure: results from the Watchman Left Atrial Appendage System for Embolic Protection in Patients with AF (PROTECT AF) clinical trial and the Continued Access Registry.</a> Circulation. 123, 417-424 (2011).</li></ol>

Dr. Möbius-Winkler, Dr. Dähnert e Prof Schuler participaram no Julgamento de AF de proteção. Dr. Möbius-Winkler trabalha como inspetor de Implantação WATCHMAN para Atritech Inc. e Boston Scientific.

O procedimento para o implante percutâneo da WATCHMAN deixou dispositivo de fecho atrial apêndice descrito aqui, tem sido demonstrado em ensaios clínicos para ser 16 viável, não-inferior a varfarina terapia 2, 17 e segura. Embora em todos os estudos houve uma maior taxa de complicações no grupo que recebeu o implante 2,16,17, os dados do estudo AF proteger e estudar registro PAC, que avaliou a segurança, sugere que as complicações associadas com a implantação do guarda pode ser em grande parte atribuída à inexperiência do operador. A freqüência de taxas de eventos de segurança foi inicialmente elevado, mas diminuiu ao longo do tempo 17. O método aqui apresentado destaca diversas etapas críticas na prevenção de complicações processuais. Durante o estudo piloto, três eventos de segurança ocorreu como resultado de falha do dispositivo. Em dois indivíduos o dispositivo embolizado, e em uma pessoa o fio fraturado durante o implanteinjeção. Embora esses eventos ocorreram em dispositivos de primeira geração, e que não ocorreu no dispositivo de segunda geração, o sistema WATCHMAN deve sempre ser cuidadosamente examinado antes de utilizar 16. As complicações mais comuns associadas com o procedimento são derrames pericárdicos que necessitam de intervenção e de embolia aérea. Análise de dados de imagens sugere que os derrames graves pericárdicas no ensaio AF PROTECT foram causados ​​por erro do operador durante a punção transeptal, pela manipulação do dispositivo WATCHMAN ou por manipulação dentro do LAA com a bainha para alcançar um procedimento de implante óptima. Ao utilizar um cateter pigtail o risco de perfuração do LAA pela ponta da bainha pode ser fortemente reduzido. Um derrame pericárdico provavelmente resultou de um &quot;teste de rebocador&quot; vigorosa realizada para verificar a estabilidade do dispositivo no LAA. Por esta razão, é crítica a utilização do T e fluoroscopia durante todo o procedimento para monitorizar o iprocesso mplantation. Ao verificar a estabilidade, o contraste deve ser injetado no LAA para visualizar a câmara, ou o processo deve ser continuamente monitorado com ETE. Com a observação, não há mais cabo-relacionados derrames têm sido observados. Relacionada ao procedimento acidente vascular cerebral ocorreu em 3 casos como resultado de ar embolia da bainha de acesso grande 12F transeptal. Portanto, é crítico para ser diligentes em adequadamente rubor da bainha assegurar que o ar não é aprisionado no interior da bainha 17. Além disso, em jejum antes do procedimento pode levar à desidratação resulta uma pressão esquerdo atrial baixo durante o procedimento de implante, que pode causar embolia ar. Portanto, antes da implantação do dispositivo, solução salina deve ser infundida a aumentar a pressão esquerdo do paciente atrial a cerca de 10 mmHg. Apesar do aumento da taxa de segurança de eventos com LAA oclusão em relação ao tratamento com varfarina, o resultado global com relação à morbidade / mortalidade com LAA oclusão foi improvou 17. Encerramento do apêndice atrial esquerdo é, portanto, uma alternativa promissora eficaz à terapia com varfarina contínua em pacientes com não-valvular fibrilação atrial.

the watchman left atrial appendage closure device for atrial fibrillation

A fibrilação atrial (FA) é a arritmia cardíaca mais comum, afetando cerca de 6 milhões de pessoas nos Estados Unidos 1. Desde AF afeta principalmente pessoas idosas, a sua prevalência aumenta em paralelo com a idade. Como tal, espera-se que 15,9 milhões de americanos irá ser afectada pelo ano 2050 2. Acidente vascular cerebral isquémico ocorre em 5% de pacientes não anticoagulados AF cada ano. Os tratamentos atuais para FA incluem controle de taxa, o controle do ritmo e prevenção de 3 de AVC. O American College of Cardiology, American Heart Association, e da Sociedade Européia de Cardiologia, atualmente o controle da frequência recomendada como primeiro curso de terapia para AF 3. Controlo da taxa de é conseguido através da administração de agentes farmacológicos, tais como os beta-bloqueadores, que reduzem a taxa do coração até atingir um estado menos sintomática 3. O controle do ritmo pretende voltar do coração para o seu ritmo sinusal normal e é tipicamenteconseguido através da administração de drogas antiarrítmicas, como cardioversão, amiodarona elétrica ou terapia de ablação. Métodos de controlo do ritmo, no entanto, não têm sido demonstrado ser superior à taxa de métodos de controle de 4-6. Na verdade, certos fármacos antiarrítmicos têm sido mostrados para ser associado a taxas mais elevadas de hospitalização, efeitos adversos graves 3, ou mesmo aumento da mortalidade em pacientes com defeitos estruturais do coração 7. Assim, o tratamento com anti-arrítmicos é mais frequentemente usado quando a taxa de controle de drogas são ineficazes ou contra-indicados. Taxa de controle e agentes anti-arrítmicos aliviar os sintomas de AF, incluindo palpitações, falta de ar e fadiga 8, mas não de forma confiável prevenção de eventos tromboembólicos 6. O tratamento com o fármaco anticoagulante varfarina reduz significativamente a taxa de acidente vascular cerebral ou embolia 9,10. No entanto, devido a problemas associados com a sua utilização, menos de 50%pacientes são tratados de com ele. A dose terapêutica é afetada pela droga, dieta e interações metabólicas e, portanto, exige um acompanhamento detalhado. Além disso, a varfarina tem o potencial para causar grave, por vezes letal, sangramento 2. Como alternativa, a aspirina é comumente prescritos. Enquanto a aspirina é normalmente bem tolerada, é muito menos eficaz na prevenção de acidente vascular cerebral 10. Outras alternativas para a warfarina, tais como dabigatrano 11 ou 12 rivaroxabano demonstrou não-inferioridade à varfarina com respeito aos eventos tromboembólicos (de facto, dabigatrano dada como uma dose elevada de 150 mg duas vezes por dia mostrou superioridade). Embora essas drogas têm a vantagem de eliminar preocupações dietéticas e eliminando a necessidade de um acompanhamento regular de sangue, hemorragias graves e complicações associadas, enquanto um pouco menos do que com a varfarina, continuam a ser um problema 13-15. Uma vez que 90% de FA-associados traços resultam de êmbolos que arisi a partir da aurícula esquerda (LAA) 2, uma abordagem alternativa para a warfarina terapia tem sido a de excluir a LAA usando um dispositivo implantado para interceptar os coágulos de sangue antes de sair. Aqui, nós demonstramos um procedimento para a implantação do dispositivo de fechamento WATCHMAN Esquerda Atrial apêndice. Uma cânula transeptal é inserido através da veia femoral, e sob orientação fluoroscópica, inter-atrial septo é atravessada. Uma vez que o acesso ao átrio esquerdo foi alcançado, um fio-guia é colocado na veia pulmonar superior e da bainha de Acesso vigia e dilatador são avançados sobre o fio para a aurícula esquerda. O fio-guia é removida, ea bainha de acesso é cuidadosamente avançado para dentro da porção distai do AAE ao longo de um cateter pigtail. O sistema de entrega WATCHMAN é preparado, inserido no interior da bainha de acesso, e lentamente avançado. O dispositivo WATCHMAN é então implantado no LAA. Os critérios de liberação do dispositivo são confirmadas através de fluoroscopia e ecocardiograma transesofágico (ETE) eo dispositivo de is liberado.

Watch this Scientific Journal Video about The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation at JoVE.com

The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation

O vídeo que acompanha descreve um procedimento para colocação percutânea do WATCHMAN atrial esquerda Appendage dispositivo (LAA). O WATCHMAN é um dispositivo de nitinol concebido para ser permanentemente implantado no, ou ligeiramente distai para, a abertura da aurícula esquerda (AAE) para prender os coágulos de sangue antes de sair do LAA, impedindo derrame tromboembólico.

O WATCHMAN Esquerda dispositivo de fechamento atrial Appendage para Fibrilação Atrial

Atrial fibrillation (AF) is the most common cardiac arrhythmia, affecting an estimated 6 million people in the United States 1. Since AF affects primarily ...

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Research

JoVE Journal

Medicine

83.1K visualizações.  University of Leipzig Heart Center. O vídeo que acompanha descreve um procedimento para colocação percutânea do WATCHMAN atrial esquerda Appendage dispositivo (LAA). O WATCHMAN é um dispositivo de nitinol concebido para ser permanentemente implantado no, ou ligeiramente distai para, a abertura da aurícula esquerda (AAE) para prender os coágulos de sangue antes de sair do LAA, impedindo derrame tromboembólico.

Vídeo: The WATCHMAN Left Atrial Appendage Closure Device for Atrial Fibrillation

High-Resolution Endocardial and Epicardial Optical Mapping in a Sheep Model of Stretch-Induced Atrial Fibrillation

Atrial fibrillation (AF) is a complex cardiac arrhythmia with high morbidity and mortality.1,2 It is the most common sustained cardiac rhythm disturbance seen in clinical practice and its prevalence is expected to increase in the coming years.3 Increased intra-atrial pressure and dilatation have been long recognized to lead to AF,1,4 which highlights the relevance of using animal models and stretch to study AF dynamics. Understanding the mechanisms underlying AF requires visualization of the cardiac electrical waves with high spatial and temporal resolution. While high-temporal resolution can be achieved by conventional electrical mapping traditionally used in human electrophysiological studies, the small number of intra-atrial electrodes that can be used simultaneously limits the spatial resolution and precludes any detailed tracking of the electrical waves during the arrhythmia. The introduction of optical mapping in the early 90's enabled wide-field characterization of fibrillatory activity together with sub-millimeter spatial resolution in animal models5,6 and led to the identification of rapidly spinning electrical wave patterns (rotors) as the sources of the fibrillatory activity that may occur in the ventricles or the atria.7-9 Using combined time- and frequency-domain analyses of optical mapping it is possible to demonstrate discrete sites of high frequency periodic activity during AF, along with frequency gradients between left and right atrium. The region with fastest rotors activates at the highest frequency and drives the overall arrhythmia.10,11 The waves emanating from such rotor interact with either functional or anatomic obstacles in their path, resulting in the phenomenon of fibrillatory conduction.12 Mapping the endocardial surface of the posterior left atrium (PLA) allows the tracking of AF wave dynamics in the region with the highest rotor frequency. Importantly, the PLA is the region where intracavitary catheter-based ablative procedures are most successful terminating AF in patients,13 which underscores the relevance of studying AF dynamics from the interior of the left atrium. Here we describe a sheep model of acute stretch-induced AF, which resembles some of the characteristics of human paroxysmal AF. Epicardial mapping on the left atrium is complemented with endocardial mapping of the PLA using a dual-channel rigid borescope c-mounted to a CCD camera, which represents the most direct approach to visualize the patterns of activation in the most relevant region for AF maintenance.

This report provides a detailed description of the methodology and results of simultaneous endocardial and epicardial optical mapping of electrical excitation in the intact left atrium of a Langendorff-perfused sheep heart during stretch-induced atrial fibrillation.

Alta Resolução Mapeamento endocárdico e epicárdico óptico em um modelo de Ovinos de Stretch Induzida por Fibrilação Atrial

 Atrial fibrillation (AF) is a complex cardiac arrhythmia with high morbidity and mortality.1,2 It is the most common sustained cardiac rhythm disturbance ...

Medicina

Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting millions of individuals worldwide 1-3. The rapid, irregular, and disordered electrical activity in the atria gives rise to palpitations, fatigue, dyspnea, chest pain and dizziness with or without syncope 4, 5. Patients with AF have a five-fold higher risk of stroke 6.
Oral anticoagulation (OAC) with warfarin is commonly used for stroke prevention in patients with AF and has been shown to reduce the risk of stroke by 64% 7. Warfarin therapy has several major disadvantages, however, including bleeding, non-tolerance, interactions with other medications and foods, non-compliance and a narrow therapeutic range 8-11. These issues, together with poor appreciation of the risk-benefit ratio, unawareness of guidelines, or absence of an OAC monitoring outpatient clinic may explain why only 30-60% of patients with AF are prescribed this drug 8.
The problems associated with warfarin, combined with the limited efficacy and/or serious side effects associated with other medications used for AF 12,13, highlight the need for effective non-pharmacological approaches to treatment. One such approach is catheter ablation (CA), a procedure in which a radiofrequency electrical current is applied to regions of the heart to create small ablation lesions that electrically isolate potential AF triggers 4. CA is a well-established treatment for AF symptoms 14, 15, that may also decrease the risk of stroke. Recent data showed a significant decrease in the relative risk of stroke and transient ischemic attack events among patients who underwent ablation compared with those undergoing antiarrhythmic drug therapy 16.
Since the left atrial appendage (LAA) is the source of thrombi in more than 90% of patients with non-valvular atrial fibrillation 17, another approach to stroke prevention is to physically block clots from exiting the LAA. One method for occluding the LAA is via percutaneous placement of the WATCHMAN LAA closure device. The WATCHMAN device resembles a small parachute. It consists of a nitinol frame covered by fabric polyethyl terephthalate that prevents emboli, but not blood, from exiting during the healing process. Fixation anchors around the perimeter secure the device in the LAA (Figure 1). To date, the WATCHMAN is the only implanted percutaneous device for which a randomized clinical trial has been reported. In this study, implantation of the WATCHMAN was found to be at least as effective as warfarin in preventing stroke (all-causes) and death (all-causes) 18. This device received the Conformit&eacute; Europ&eacute;enne (CE) mark for use in the European Union for warfarin eligible patients and in those who have a contraindication to anticoagulation therapy 19.
Given the proven effectiveness of CA to alleviate AF symptoms and the promising data with regard to reduction of thromboembolic events with both CA and WATCHMAN implantation, combining the two procedures is hoped to further reduce the incidence of stroke in high-risk patients while simultaneously relieving symptoms. The combined procedure may eventually enable patients to undergo implantation of the WATCHMAN device without subsequent warfarin treatment, since the CA procedure itself reduces thromboembolic events. This would present an avenue of treatment previously unavailable to patients ineligible for warfarin treatment because of recurrent bleeding 20 or other warfarin-associated problems.
The combined procedure is performed under general anesthesia with biplane fluoroscopy and TEE guidance. Catheter ablation is followed by implantation of the WATCHMAN LAA closure device. Data from a non-randomized trial with 10 patients demonstrates that this procedure can be safely performed in patients with a CHADS2 score of greater than 1 21. Further studies to examine the effectiveness of the combined procedure in reducing symptoms from AF and associated stroke are therefore warranted.

Catheter ablation is combined with placement of the WATCHMAN Left Atrial Appendage Closure Device to prevent ischemic stroke in a patient with non-valvular atrial fibrillation.

Ablação por cateter em combinação com o fechamento do apêndice atrial esquerdo para Fibrilação Atrial

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, affecting millions of individuals worldwide 1-3. The rapid, irregular, and ...

Robotic Ablation of Atrial Fibrillation

Background: Pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). During PVI an electrical conduction block between pulmonary vein (PV) and left atrium (LA) is created. This conduction block prevents AF, which is triggered by irregular electric activity originating from the PV. However, transmural atrial lesions are required which can be challenging. Re-conduction and AF recurrence occur in 20 - 40% of the cases. Robotic catheter systems aim to improve catheter steerability. Here, a procedure with a new remote catheter system (RCS), is presented. Objective of this article is to show feasibility of robotic AF ablation with a novel system. Materials and Methods: After interatrial trans-septal puncture is performed using a long sheath and needle under fluoroscopic guidance. The needle is removed and a guide wire is placed in the left superior PV. Then an ablation catheter is positioned in the LA, using the sheath and wire as guide to the LA. LA angiography is performed over the sheath. A circular mapping catheter is positioned via the long sheath into the LA and a three-dimensional (3-D) anatomical reconstruction of the LA is performed. The handle of the ablation catheter is positioned in the robotic arm of the Amigo system and the ablation procedure begins. During the ablation procedure, the operator manipulates the ablation catheter via the robotic arm with the use of a remote control. The ablation is performed by creating point-by-point lesions around the left and right PV ostia. Contact force is measured at the catheter tip to provide feedback of catheter-tissue contact. Conduction block is confirmed by recording the PV potentials on the circular mapping catheter and by pacing maneuvers. The operator stays out of the radiationfield during ablation. Conclusion: The novel catheter system allows ablation with high stability on low operator fluoroscopy exposure.

Pulmonary vein isolation (PVI) with an ablation catheter is a curative treatment for atrial fibrillation (AF). Robotic catheter systems aim to improve catheter steerability. Here, a procedure with a new robotic catheter system is presented. The goal of the procedure is electrical block between pulmonary vein and left atrium.

Robotic Ablação de Fibrilação Atrial

Background: Pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). During PVI an electrical conduction block between ...

Left Atrial Stenosis Induced Pulmonary Venous Arterialization and Group 2 Pulmonary Hypertension in Rat

The mechanism of mitral stenosis-induced pulmonary venous arterialization and group 2 pulmonary hypertension (PH) is unclear. There is no rodent model of group 2 PH, due to mitral stenosis (MS), to facilitate the investigation of disease mechanisms and potential therapeutic strategies. We present a novel rat model of pulmonary venous congestion-induced pulmonary venous arterialization and group 2 PH caused by left atrial stenosis (LAS). LAS is achieved by constricting the left atrium using a half-closed titanium clip. After the LAS surgery, a rat model with a transmitral inflow velocity greater than or equal to 2.0 m/s on echocardiography gradually develops pulmonary venous arterialization and group 2 PH over an 8- to 10-week period. In this protocol, we provide the step-by-step procedure of how to perform the LAS surgery. The presented LAS rat model mimics MS in humans and is useful for studying the underlying molecular mechanism of pulmonary venous arterialization and for the preclinical evaluation of therapies for group 2 PH.

Left atrial stenosis (LAS) is a novel surgical technique used for studying group 2 pulmonary hypertension (PH) and mechanisms underlying pulmonary venous arterialization. Here, we present a protocol to constrict the left atrium using a titanium clip to cause pulmonary venous arterialization and moderate PH in a rat.

Estenose Atrial Esquerdo induzida Arterialization venoso pulmonar e hipertensão pulmonar do grupo 2 no rato

The mechanism of mitral stenosis-induced pulmonary venous arterialization and group 2 pulmonary hypertension (PH) is unclear. There is no rodent model of ...

Cooling or Warming the Esophagus to Reduce Esophageal Injury During Left Atrial Ablation in the Treatment of Atrial Fibrillation

Ablation of the left atrium using either radiofrequency (RF) or cryothermal energy is an effective treatment for atrial fibrillation (AF) and is the most frequent type of cardiac ablation procedure performed. Although generally safe, collateral injury to surrounding structures, particularly the esophagus, remains a concern. Cooling or warming the esophagus to counteract the heat from RF ablation, or the cold from cryoablation, is a method that is used to reduce thermal esophageal injury, and there are increasing data to support this approach. This protocol describes the use of a commercially available esophageal temperature management device to cool or warm the esophagus to reduce esophageal injury during left atrial ablation. The temperature management device is powered by standard water-blanket heat exchangers, and is shaped like a standard orogastric tube placed for gastric suctioning and decompression. Water circulates through the device in a closed-loop circuit, transferring heat across the silicone walls of the device, through the esophageal wall. Placement of the device is analogous to the placement of a typical orogastric tube, and temperature is adjusted via the external heat-exchanger console.

The goal of this protocol is to describe the use of esophageal temperature modulation to counteract esophageal thermal injury from left atrial ablation for the treatment of atrial fibrillation.

Resfriamento ou Aquecimento do Esôfago para reduzir a lesão esofágica durante a ablação atrial esquerda no tratamento da fibrilação atrial

Ablation of the left atrium using either radiofrequency (RF) or cryothermal energy is an effective treatment for atrial fibrillation (AF) and is the most ...

Echocardiographic Evaluation of Atrial Communications before Transcatheter Closure

Transthoracic (TTE) and transesophageal echocardiography (TEE) is the standard imaging method for atrial septal defect (ASD) and patent foramen ovale (PFO) detection, for patient selection for transcatheter ASD/PFO closure,&#160;for intraoperative guidance and for long-term follow-up. The size, shape, location and the number of the atrial communications schould be determined. The accuracy of PFO detection can be improved by using agitated saline together with maneuvers to transiently increase the right atrial (RA) pressure. The appearance of microbubbles in the left atrium (LA) within 3 cardiac cycles after opacification of the RA is considered positive for the presence of an intracardiac shunt. Three dimensional TEE identifies further septal fenestrations and describes the dynamic morphology of ASD/PFO and atrial septal aneurysm. Follow-up evaluations with TTE is recommended at 1, 6, and 12 months after the procedure, with a subsequent evaluation every year. Previous studies showed an increased incidence of atrial arrhythmias early after device closure. Speckle tracking analysis may help to understand functional left atrial remodeling following percutaneous closure and its impact on atrial arrhythmias.

Transthoracic (TTE) and transesophageal (TEE) echocardiography represent the basic imaging tools for interatrial septum examination. Three dimensional (3D) TEE provides incremental information in the assessment of the interatrial septum. Further advanced echocardiography techniques using speckle tracking echocardiography are applied for sensitive volumetric and functional assessment of the heart chambers.&#160;

Avaliação Ecocardiográfica das Comunicações Atrial antes do fechamento do Transcateter

Transthoracic (TTE) and transesophageal echocardiography (TEE) is the standard imaging method for atrial septal defect (ASD) and patent foramen ovale ...

Sterile Pericarditis in Aachener Minipigs As a Model for Atrial Myopathy and Atrial Fibrillation

Atrial fibrillation (AF) is the most common arrhythmia caused by structural remodeling of the atria, also called atrial myopathy. Current therapies only target the electrical abnormalities and not the underlying atrial myopathy. For the development of novel therapies, a reproducible large animal model of atrial myopathy is necessary. This paper presents a model of sterile pericarditis-induced atrial myopathy in Aachener minipigs. Sterile pericarditis was induced by spraying sterile talcum and leaving a layer of sterile gauze over the atrial epicardial surface. This led to inflammation and fibrosis, two crucial components of the pathophysiology of atrial myopathy, making the atria susceptible to the induction of AF. Two pacemaker electrodes were positioned epicardially on each atrium and connected to two pacemakers from different manufacturers. This strategy allowed for repeated non-invasive atrial programmed stimulation to determine the inducibility of AF at specified time points after surgery. Different protocols to test AF inducibility were used. The advantages of this model are its clinical relevance, with AF inducibility and the rapid induction of inflammation and fibrosis-both present in atrial myopathy-and its reproducibility. The model will be useful in the development of novel therapies targeting atrial myopathy and AF.

We describe a sterile pericarditis model in minipigs to study atrial myopathy and atrial fibrillation (AF). We present surgical and anesthetic techniques, strategies for vascular access, and a protocol to study the inducibility of AF.

Pericardite estéril em Miniporcos Aachener como modelo para miopatia atrial e fibrilação atrial

Atrial fibrillation (AF) is the most common arrhythmia caused by structural remodeling of the atria, also called atrial myopathy. Current therapies only ...

Transesophageal Atrial Burst Pacing for Atrial Fibrillation Induction in Rats

Animal studies have brought important insights into our understanding regarding atrial fibrillation (AF) pathophysiology and therapeutic management. Reentry, one of the main mechanisms involved in AF pathogenesis, requires a certain mass of myocardial tissue in order to occur. Due to the small size of the atria, rodents have long been considered 'resistant' to AF. Although spontaneous AF has been shown to occur in rats, long-term follow-up (up to 50 weeks) is required for the arrhythmia to occur in those models. The present work describes an experimental protocol of transesophageal atrial burst pacing for rapid and efficient induction of AF in rats. The protocol can be successfully used in rats with healthy or remodeled hearts, in the presence of a wide variety of risk factors, allowing the study of AF pathophysiology, identification of novel therapeutic targets, and evaluation of novel prophylactic and/or therapeutic strategies.

The present work describes an experimental protocol of transesophageal atrial burst pacing for efficient induction of atrial fibrillation (AF) in rats. The protocol can be used in rats with healthy or remodeled hearts, allowing the study of AF pathophysiology, identification of novel therapeutic targets, and evaluation of new therapeutic strategies.

Transesofágico Atrial Burst Pacing para Indução de Fibrilação Atrial em Ratos

Animal studies have brought important insights into our understanding regarding atrial fibrillation (AF) pathophysiology and therapeutic management. ...

Estimating Bilateral Atrial Function by Cardiovascular Magnetic Resonance Feature Tracking in Patients with Paroxysmal Atrial Fibrillation

Atrial fibrillation (AF) is the most common form of arrhythmia. Atrial remodeling is considered the most critical mechanism for the presence and development of atrial fibrillation. Also, atrial remodeling can lead to the enlargement and dysfunction of the left atrium (LA), resulting in thrombosis and heart failure. Functional changes in left atrial strain and strain rate occur before structural alterations and are closely associated with structural remodeling and left atrial fibrosis. These parameters are sensitive biomarkers for atrial function. Cardiac magnetic resonance feature tracking (CMR-FT) is a novel, non-invasive, post-processing technique that can evaluate left atrial strain and strain rate. The CMR-FT was utilized in this investigation to assess the bilateral atrium strain rate in individuals with paroxysmal AF. Modifications in each segmental strain were evaluated using segmental analysis. The CMR-FT is recommended for non-invasive evaluations in the clinical assessment of atrial strain among existing strain imaging techniques. Further, it is a flexible parameter measurement with good reproducibility, high soft-tissue resolution, and post-processing based on standard cine balanced steady-state free precision (bSSFP) long-axis images without requiring a new sequence acquisition.

The atrial function is associated with the strain and strain rate. The cardiac magnetic resonance feature tracking (CMR-FT) technique was used in this study to quantify left and right atrial global and segmental longitudinal strain and strain rate in individuals with paroxysmal atrial fibrillation.

Estimando a Função Atrial Bilateral por Rastreamento de Características de Ressonância Magnética Cardiovascular em Pacientes com Fibrilação Atrial Paroxística

Atrial fibrillation (AF) is the most common form of arrhythmia. Atrial remodeling is considered the most critical mechanism for the presence and ...

Reduced Procedure Time and Variability with Active Esophageal Cooling During Radiofrequency Ablation for Atrial Fibrillation

Various methods are utilized during radiofrequency (RF) pulmonary vein isolation (PVI) for the treatment of atrial fibrillation (AF) to protect the esophagus from inadvertent thermal injury. Active esophageal cooling is increasingly being used over traditional luminal esophageal temperature (LET) monitoring, and each approach may influence procedure times and the variability around those times. The objective of this study is to measure the effects on procedure time and variability in procedure time of two different esophageal protection strategies utilizing advanced informatics techniques to facilitate data extraction. Trained clinical informaticists first performed a contextual inquiry in the catheterization laboratory to determine laboratory workflows and observe the documentation of procedural data within the electronic health record (EHR). These EHR data structures were then identified in the electronic health record reporting database, facilitating data extraction from the EHR. A manual chart review using a REDCap database created for the study was then performed to identify additional data elements, including the type of esophageal protection used. Procedure duration was then compared using summary statistics and standard measures of dispersion.&#160;A total of 164 patients underwent radiofrequency PVI over the study timeframe; 63 patients (38%) were treated with LET monitoring, and 101 patients (62%) were treated with active esophageal cooling. The mean procedure time was 176 min (SD of 52 min) in the LET monitoring group compared to 156 min (SD of 40 min) in the esophageal cooling group (P = 0.012). Thus, active esophageal cooling during PVI is associated with reduced procedure time and reduced variation in procedure time when compared to traditional LET monitoring.

This study utilized advanced informatics techniques to compare procedure duration in patients undergoing radiofrequency atrial ablation treated with active esophageal cooling to those treated with traditional luminal esophageal temperature monitoring. Contextual inquiry, workflow analysis, and data mapping were utilized. The findings demonstrated reduced procedure time and variability with active cooling.

Tempo de procedimento reduzido e variabilidade com resfriamento esofágico ativo durante a ablação por radiofrequência para fibrilação atrial

Various methods are utilized during radiofrequency (RF) pulmonary vein isolation (PVI) for the treatment of atrial fibrillation (AF) to protect the ...