Impact of catheter ablation procedure on optical coherence tomography angiography findings in patients with ventricular arrhythmia.

OBJECTIVE: Catheter ablation procedure may cause retinal complications associated with the risk of thromboembolism. We aimed to evaluate retina and optic disc microvascularity with optical coherence tomography angiography before and after the catheter ablation process in patients with ventricular arrhythmia. METHODS: A total of 40 eyes of 21 ventricular arrhythmia patients were included in this cross-sectional study. Demographic characteristics and ophthalmic examination findings of patients were recorded. optical coherence tomography angiography measurements were evaluated before (group 1) and after (group 2) catheter ablation. Optical coherence tomography angiography was applied to all eyes with 6×6 mm sections for the macula and 4.5×4.5 mm sections for the optic nerve head. Foveal retinal thickness, peripapillary retinal nerve fiber layer thickness, vessel density in different parts of the retina, and optic disc were analyzed. RESULTS: The mean age of ventricular arrhythmia patients was 53.48±13.02 years. In all, 13 (61.9%) of the patients were males and 8 (38.1%) were females. There was no significant difference between the groups in terms of average, inferior, superior, and temporal retinal nerve fiber layer thicknesses, foveal avascular area, flow areas, superficial and deep vessel densities, and optic disc capillary densities of the optic disc. However, when compared with group 1, significantly lower values in foveal retinal thickness and higher values in nasal retinal nerve fiber layer thickness were observed in group 2 (248.42±20.50 vs. 247.20±20.44, p<0.001 and 94.22±18.43 vs. 96.12±20.18, p=0.044, respectively). CONCLUSION: Although foveal retinal thickness and nasal retinal nerve fiber layer thickness are affected in patients undergoing catheter ablation for ventricular arrhythmia, the stable retinal and optic disc vessel densities can be explained by the administration of effective anticoagulants during the procedure.

Long-Term Ventricular Pacing Dependency and Pacemaker Implantation Predictors after Transcatheter Aortic Valve Replacement - A 1-Year Follow-Up. / Dependência de Pacing a Longo-Prazo e Preditores de Implante de Pacemaker após Implante Percutâneo de Prótese Valvular Aórtica ­ 1 Ano de Seguimento.

BACKGROUND: Conduction disturbances (CD) are the most frequent complication after transcatheter aortic valve replacement (TAVR), and there continues to be a lack of consensus on their management. OBJECTIVE: To assess new CD and permanent pacemaker (PPM) implantation after TAVR and to evaluate the ventricular pacing percentage (VP) up to 1 year of follow-up. METHODS: Patients who underwent TAVR from October 2014 to November 2019 were enrolled; patients with previous PPM were excluded. Clinical, procedure, ECG, and PPM data were collected up to 1 year after implantation. The significance level adopted in the statistical analysis was 0.05. RESULTS: A total of 340 patients underwent TAVR. The most frequent CD was the new left bundle branch block (LBBB; 32.2%), which 56% resolved after 6 months. Right bundle branch block (RBBB) was the biggest risk factor for advanced atrioventricular block (AVB) [OR=8.46; p<0.001] and PPM implantation [OR=5.18, p<0.001], followed by previous low-grade AVB [OR=2.25; p=0.016 for PPM implantation]. Regarding procedure characteristics, newer generation valves and valve-in-valve procedures were associated with fewer CDs. Overall, 18.5% of patients had a PPM implanted post-TAVR. At first PPM evaluation, patients with advanced AVB had a median percentage of VP of 80% and 83% at one year. Regarding patients with LBBB plus low-grade AVB, median VP was lower (6% at first assessment, p=0.036; 2% at one year, p = 0.065). CONCLUSION: LBBB was the most frequent CD after TAVR, with more than half being resolved in the first six months. RBBB was the major risk factor for advanced AVB and PPM implantation. Advanced AVB was associated with a higher percentage of VP at 1 year of follow-up.

FUNDAMENTO: Os distúrbios de condução (DC) são a complicação mais frequente após a substituição da válvula aórtica transcateter (TAVR) e ainda não há consenso sobre seu tratamento. OBJETIVO: Avaliar novos DC e implante de marca-passo definitivo (MPD) após a TAVR e avaliar a porcentagem de estimulação ventricular (EV) até 1 ano de acompanhamento. MÉTODOS: Pacientes submetidos a TAVR de outubro de 2014 a novembro de 2019 foram cadastrados; pacientes com MPD anterior foram excluídos. Dados clínicos, do procedimento, do ECG e do MPD foram coletados até 1 ano após o implante. O nível de significância adotado para a análise estatística foi 0,05%. RESULTADOS: Um total de 340 indivíduos foram submetidos a TAVR. O DC mais comum foi bloqueio de ramo esquerdo novo (BRE; 32,2%), sendo que 56% destes foram resolvidos após 6 meses. O bloqueio do ramo direito (BRD) foi o maior fator de risco para bloqueio atrioventricular avançado (BAV) [RC=8,46; p<0,001] e implante de MPD [RC=5,18; p<0,001], seguido de BAV de baixo grau prévio [RC=2,25; p=0,016 para implante de MPD]. Em relação às características do procedimento, válvulas de gerações mais recentes e procedimentos de válvula-em-válvula foram associados a menos DC. No total, 18,5% dos pacientes tiveram MPD implantado após a TAVR. Na primeira avaliação do MPD, pacientes com BAV avançado tinham uma porcentagem mediana de EV de 80%, e, após um ano, de 83%. Em relação aos pacientes com BRE e BAV de baixo grau, a EV mediana foi mais baixa (6% na primeira avaliação, p=0,036; 2% após um ano, p = 0,065). CONCLUSÃO: O BRE foi o DC mais frequente após a TAVR, com mais da metade dos casos se resolvendo nos primeiros 6 meses. O BRD foi o principal fator de risco para BAV avançado e implante de MPD. O BAV avançado foi associado a uma porcentagem mais alta de EV no acompanhamento de 1 ano.

Thermal ablation effects on rotors that characterize functional re-entry cardiac arrhythmia.

Thermal ablation is a well-established successful treatment for cardiac arrhythmia, but it still presents limitations that require further studies and developments. In the rotor-driven functional re-entry arrhythmia, tissue heterogeneity results on the generation of spiral/scroll waves and wave break dynamics that may cause dangerous sustainable fibrillation. The selection of the target region to perform thermal ablation to mitigate this type of arrhythmia is challenging, since it considerably affects the local electrophysiology dynamics. This work deals with the numerical simulation of the thermal ablation of a cardiac muscle tissue and its effects on the dynamics of rotor-driven functional re-entry arrhythmia. A non-homogeneous two-dimensional rectangular region is used in the present numerical analysis, where radiofrequency ablation is performed. The electrophysiology problem for the propagation of the action potential in the cardiac tissue is simulated with the Fenton-Karma model. Thermal damage caused to the tissue by the radiofrequency heating is modeled by the Arrhenius equation. The effects of size and position of a heterogeneous region in the original muscle tissue were first analyzed, in order to verify the possible existence of the functional re-entry arrhythmia during the time period considered in the simulations. For each case that exhibited re-entry arrhythmia, six different ablation procedures were analyzed, depending on the position of the radiofrequency electrode and heating time. The obtained results revealed the effects of different model parameters on the existence and possible mitigation of the functional re-entry arrhythmia.

Intracardiac echocardiography as an adjunctive tool for accessory pathway ablation in Ebstein anomaly.

BACKGROUND: Accessory pathway (AP)-related arrhythmias are frequent in patients with Ebstein anomaly (EA), and arrhythmia recurrence after catheter ablation remains high despite current technological developments. METHODS: Case series report of patients with EA who were taken to an accessory pathway ablation procedure and where clinical, procedure, and follow-up data are described. In all cases, mapping of the true tricuspid annulus guided by intracardiac ultrasound was used. RESULTS: Six patients with EA underwent an ablation procedure using ICE to delineate the true tricuspid annulus. The duration of the procedure was 253.33 ± 60.92 min, with an acute success of 100%. After a mean follow-up of 16.16 ± 7.7 months, no recurrences of tachycardia were documented, and all patients were free of antiarrhythmic medications. CONCLUSION: Intraprocedural ICE helps to delineate the true tricuspid annulus that contains the APs, facilitating mapping and ablation. We hypothesize that the systematic use of ICE in this scenario improves ablation efficacy while reducing complications, but this must be verified in prospective studies.

Renal denervation for the treatment of ventricular arrhythmias: A systematic review and meta-analysis.

INTRODUCTION: Ventricular arrhythmias (VAs) are a major cause of morbidity and mortality in patients with heart disease. Recent studies evaluated the effect of renal denervation (RDN) on the occurrence of VAs. We conducted a systematic review and meta-analysis to determine the efficacy and safety of this procedure. METHODS AND RESULTS: A systematic search of the literature was performed to identify studies that evaluated the use of RDN for the management of VAs. Primary outcomes were reduction in the number of VAs and implantable cardioverter-defibrillator (ICD) therapies. Secondary outcomes were changes in blood pressure and renal function. Ten studies (152 patients) were included in the meta-analysis. RDN was associated with a reduction in the number of VAs, antitachycardia pacing, ICD shocks, and overall ICD therapies of 3.53 events/patient/month (95% confidence interval [CI] = -5.48 to -1.57), 2.86 events/patient/month (95% CI = -4.09 to -1.63), 2.04 events/patient/month (95% CI = -2.12 to -1.97), and 2.68 events/patient/month (95% CI = -3.58 to -1.78), respectively. Periprocedural adverse events occurred in 1.23% of patients and no significant changes were seen in blood pressure or renal function. CONCLUSIONS: In patients with refractory VAs, RDN was associated with a reduction in the number of VAs and ICD therapies, and was shown to be a safe procedure.

Permanent Pacemaker Post Cardiac Surgery: where do we Stand?

Abstract Cardiac arrhythmias and requirement for permanent pacemaker (PPM) post open-heart surgery are some of the complications that can contribute to significant morbidities postoperatively and delay in normal recovery if not treated promptly. The reported rate of a PPM following isolated, elective coronary artery bypass grafting is < 1%, while following aortic or mitral valve surgery it is reported to be < 5%. There are several perioperative factors that can contribute to the increased likelihood of PPM requirement including preoperative rhythm, severity and location of cardiac ischaemia, perioperative variables, and the cardiac procedures performed. Optimization of such factors can possibly lead to a lower rate of PPM and, therefore, a lower rate of complications. This literature review focuses on PPM following each procedural type and how to minimize it.

Radiofrequency ablation of supraventricular arrhythmias after orthotopic heart transplantation: Long-term follow-up of a single-center experience.

BACKGROUND: Supraventricular arrhythmias (SVAs), commonly managed with radiofrequency ablation (RFA), may occur after orthotopic heart transplantation (OHT). METHODS: We retrospectively assessed 514 consecutive patients (pts.) undergoing OHT between January 1990 and July 2016 in a single-center. Patients with SVAs managed with RFA were included. Mechanisms of genesis of SVAs, association with surgical techniques and outcomes, were analyzed. RESULTS: Of 514 pts undergoing OHT, 53% (272 pts.) were managed with bicaval (BC) technique and 47% (242 pts.) with biatrial (BA) technique. Mean follow-up 10 ± 8.4 years. Nine pts. (1.7%) developed SVA requiring RFA. The BC technique was performed in 4 pts., 3 pts. presented cavotricuspid isthmus-dependent atrial flutter (CTI AFL), and 1 pt. double loop AFL. Five pts. were managed with BA technique, 4 pts. presented CTI AFL, and 1 pt. atrial tachycardia (AT). Mean time between OHT and SVA occurrence was 6.6 ± 5.5 years. The procedure was successful in 89% (8 pts.). Arrhythmia recurrence was seen in 3 pts (37%), all with BA technique. CONCLUSION: Supraventricular arrhythmias in heart transplantation may be associated with the surgical scar. Identifying the mechanism is vital to choose the appropriate treatment with radiofrequency ablation.

Translational Approach for Percutaneous Interventions for the Treatment of Cardiac Arrhythmias

Abstract New translational concepts on cellular and tissue substrate of cardiac arrhythmias have been responsible for the development of non-pharmacological interventions, with important achievements compared to the conventional approach with antiarrhythmic drugs. In addition, the increasing knowledge of anatomical and electrophysiological studies, sophisticated mapping methods, special catheters, and controlled clinical trials have favored the progression of ablation of tachyarrhythmias, particularly of ventricular tachyarrhythmias and atrial fibrillation.

Recommendations for the organization of electrophysiology and cardiac pacing services during the COVID-19 pandemic : Latin American Heart Rhythm Society (LAHRS) in collaboration with: Colombian College Of Electrophysiology, Argentinian Society of Cardiac Electrophysiology (SADEC), Brazilian Society Of Cardiac Arrhythmias (SOBRAC), Mexican Society Of Cardiac Electrophysiology (SOMEEC).

COVID-19 is a rapidly evolving public health emergency that has largely impacted the provision of healthcare services around the world. The challenge for electrophysiology teams is double; on one side preventing disease spread by limiting all nonessential face-to-face interactions, but at the same time ensuring continued care for patients who need it. These guidelines contain recommendations regarding triaging in order to define what procedures, device checks and clinic visits can be postponed during the pandemic. We also discuss best practices to protect patients and healthcare workers and provide guidance for the management of COVID-19 patients with arrhythmic conditions.

Catheter ablation of the parahisian accessory pathways from the aortic cusps-Experience of 20 cases-Improving the mapping strategy for better results.

INTRODUCTION: Catheter ablation of the parahisian accessory pathways (PHAP) has been established as the definitive therapy for this type of arrhythmia. However, the PHAP proximity to the normal atrioventricular conduction system makes the procedure technically challenging. Here, we have reported a case series of 20 patients with PHAP who underwent aortic access ablation to evaluate the safety and efficacy of this approach in the PHAP ablation. METHODS AND RESULTS: The ablation through the aortic cusps was the successful approach in 13 of 20 (65%) of the cases. In 11 patients, the aortic approach was the initial strategy for ablation, and the accessory pathway was eliminated in seven (63.6%) of them. The aortic approach followed a failed right-sided attempt in nine patients. In six (66.7%) patients, the ablation was successful with the aortic approach. The only independent predictor for the successful ablation with each approach was the earliest ventricular activation before delta wave (predelta time) and a right-sided earliest ventricular activation of more than 23 ms had high sensitivity and specificity for right-sided success. Systematically using the two strategies (right and left approaches), the ablation of the PHAP was successful in 18 (90%) patients. CONCLUSION: The aortic approach seems to be a safe and effective strategy for the ablation of PHAP. It can be used when the right-sided approach fails or even considered as an initial strategy when the predelta time is less than 23 ms in the right septal region. When combining the right- and left-sided approaches, the success rate is high. We believe that the retrograde aortic approach remains a key tool for this challenging ablation.

Cardiac sympathetic denervation for conventional treatment refractory arrhythmias / Denervación simpática cardíaca en arritmias refractarias al tratamiento convencional

Abstract Objective: Cardiac sympathetic denervation (CSD) using video-assisted thoracoscopy is a therapeutic alternative for cardiac arrhythmias refractory to conventional treatment in patients with ventricular structural heart disease, mainly due to ischemia, and in patients with hereditary conditions associated with sudden death such as long QT syndrome. In general, it is performed in cases with recurrent episodes of ventricular tachycardia or electrical storm, in spite of conventional treatment. The objective of this study is to show the experience of this institution with DSCI in refractory patients to conventional management and the results derived from its application. Methods: This was an observational retrospective study. The records of patients with a history of ventricular arrhythmias treated in our center with pharmacological treatment, catheter ablation, or implantation of an implantable cardioverter-defibrillator (ICD), who underwent video-assisted CSD were analyzed and described. Results: A total of six patients were included in the study. Patients with structural heart disease were the most frequent, median age was 56 � 16 years; 67% were male. The procedure evolved without complications in any of the patients and an overall significant improvement was observed. A 24-month follow-up was conducted; two patients had recurrence episodes presenting as slow ventricular tachycardia without severe symptoms and a third patient presented an episode of ventricular fibrillation aborted by the ICD. Conclusion: Video-assisted CSD should be considered as a treatment option for patients with potentially dangerous arrhythmias that do not respond to conventional treatment, especially in recurrent ventricular tachycardia.

Resumen Objetivo: La denervación simpática cardiaca izquierda (DSCI) por toracoscopia se ha convertido en una alternativa terapéutica para el manejo de arritmias cardíacas refractarias al tratamiento convencional en pacientes con cardiopatía estructural, principalmente isquémicos, y enfermedades hereditarias asociadas con muerte súbita como el síndrome de QT largo. Generalmente se realiza en quienes manifiestan episodios recurrentes de arritmias ventriculares o incluso tormenta eléctrica a pesar del tratamiento convencional. El objetivo de este estudio es mostrar la experiencia de esta institución con la DSCI en pacientes refractarios al manejo convencional y los resultados derivados de su aplicación. Métodos: Se revisaron los registros de 6 pacientes con antecedente de arritmias ventriculares tratados previamente con medicamentos y en algunos casos con ablación con catéter y la mayoría con desfibrilador automático implantable, que fueron llevados DSCI por toracoscopia video-asistida (VATS). Resultados: La principal enfermedad de base fue la cardiopatía estructural, la indicación más prevalente fue tormenta arrítmica incontrolable, la edad promedio fue de 56 +- 16 años, el 67% de los individuos fueron hombres. Este procedimiento no mostró complicaciones en ninguno de los pacientes y se encontró mejoría sintomática en todos los casos. Se realizó seguimiento por 24 meses; dos pacientes tuvieron recurrencias por taquicardia ventricular lenta sin síntomas severos y uno por fibrilación ventricular. Conclusion: La DSCI por VATS debe considerarse como opción terapéutica para pacientes con arritmias de difícil manejo.

Electrofisiología / Electrophysiology

El tratamiento de los trastornos del ritmo cardíaco ha sufrido recientemente una verdadera revolución. El empleo de avanzadas terapéuticas por catéter para tratar una gran variedad de arritmias, utilizando diferentes fuentes de energía, han permitido evolucionar de un tratamiento antiguamente basado casi con exclusividad en el empleo de fármacos antiarrítmicos, como terapia aguda y/o preventiva, a uno actualmente curativo, con el consiguiente avance que estos últimos métodos conllevan para la calidad de vida de nuestros pacientes y sus familias. La tendencia ha continuado con el empleo de navegadores 3 D que ya no requieren el empleo de radiación ionizante para efectuar estos procedimientos y permiten una mayor exactitud para mejorar los excelentes resultados alcanzados. El desarrollo de dispositivos eléctricos como los marcapasos, sumado a la aparición de otros más avanzados como defibriladores y resincronizadores cardíacos también ha contribuido a mejorar la expectativa de vida de muchos niños con cardiopatías diversas. La mejora evidenciada con el empleo de registradores de eventos implantables y el seguimiento mediante monitoreo a distancia de los diferentes dispositivos eléctricos han demostrado mejorar los resultados obtenidos con dichos métodos a largo plazo. Sin duda con la ayuda de la genética en un futuro cercano será posible hacer tratamientos cada vez más específicos para ayudar en casos de arritmias graves hereditarias o causadas por mutaciones en los canales iónicos de las células cardíacas. Si bien existen aún controversias respecto de algunos ítems muy puntuales los mismos se irán aclarando con las experiencias colaborativas en marcha en diferentes centros médicos especializados (AU)

Recently, treatment of heart rhythm disorders has revolutionized. The use of advanced catheter-based therapies to treat a wide spectrum of arrhythmias, using different energy sources, has led the treatment to evolve from an almost exclusively antiarrhythmic drug-based treatment, such as acute and/or preventive therapy, to a currently curative one, with the consequent advance that these latter methods add to the quality of life of our patients and their families. The trend has continued with the use of 3D navigators that no longer require the use of ionizing radiation to perform these procedures and allow greater accuracy to improve the excellent results achieved. The development of electrical devices, such as pacemakers, coupled with the emergence of more advanced devices, such as defibrillators and cardiac resynchronizers, has also been useful to improve the life expectancy of many children with different types of heart disease. The advances evidenced by the use of implantable event loggers and remote monitoring of different electrical devices have shown to improve the long-term results obtained with such methods. Undoubtedly, with the help of genetics in the near future it will be possible to develop increasingly specific therapies to treat patients with severe hereditary arrhythmias or those caused by mutations in the ion channels of the heart cells. Although controversy still exists regarding some very specific issues, these will be clarified with the collaborative experience underway at different specialized medical centers

Registro unicéntrico de ablaciones de taquiarritmias cardíacas en pacientes pediátricos. Seguridad y eficacia / Single-center registry of ablations of arrhythmogenic substrates in pediatric patients. Safety and efficacy

Introducción: Las taquiarritmias en pediatría son uno de las principales motivos cardiológicos de consulta a la guardia. Durante el primer año de vida presentan una significativa morbi-mortalidad, por lo que el tratamiento farmacológico inmediato es fundamental para reducir la misma. Hasta los 3 años existe la posibilidad de curación espontánea en un porcentaje de éstos pacientes. La indicación de procedimientos de ablación durante los primero 4 años de vida se limita a casos refractarios al tratamiento antiarrítmico, dado que cuanto menor peso presenta el paciente, más pequeño es el corazón y más riesgoso es el mismo. Las taquicardias en pacientes con cardiopatía empeora el pronóstico de la misma. A pesar que el tratamiento farmacológico ha permitido el control de la gran mayoría de ellas, en muchos casos se requieren más de una droga antiarrítmica, con mayor exposición a efectos adversos, y en muchos otros se vuelven refractarias. En las últimas 3 décadas se ha desarrollado en forma exponencial el tratamiento de las taquiarritmias por medio de la ablación por radiofrecuencia o por frío (crioablación). Estos procedimientos han permitido obtener la curación de la mayor parte de las taquiarritmias en pediatría. En nuestro trabajo se evaluaron las indicaciones de dichos procedimientos en una población pediátrica, como así también la tasa de éxito, recurrencia, y la morbimortalidad tanto globalmente, como en cada arritmia (AU)

In children, tachyarrhythmias are one of the main reasons for cardiological consultation at the Department of Emergency. In the first year of life, they are associated with significant morbiditymortality and therefore, immediate drug treatment is essential up to 3 years of age. The indication of ablation procedures during the first 4 years of life is limited to patients refractory to antiarrhythmic treatment, since the lower weight of the patient, the smaller the heart and the riskier the intervention. In patients with heart disease, tachycardia worsens the prognosis. Although pharmacological treatment controls the vast majority of tachyarrhythmias, more than one antiarrhythmic drug is often required, leading to greater exposure to adverse effects, and many become refractory. Over the past three decades, treatment of tachyarrhythmias has developed exponentially with the advent of radiofrequency or cold ablation (cryoablation). These procedures have led to the cure of most tachyarrhythmias in children. Our study assessed the indications for these procedures in a pediatric population, as well as the success and recurrence rates, and morbidity both overall and of each arrhythmia episode (AU)

Outcomes of the Conversion of the Fontan-Kreutzer Operation to a Total Cavopulmonary Connection for the Failing Univentricular Circulation.

BACKGROUND: The Fontan-Kreutzer procedure (FK) was widely performed in the past, but in the long-term generated many complications resulting in univentricular circulation failure. The conversion to total cavopulmonary connection (TCPC) is one of the options for treatment. OBJECTIVE: To evaluate the results of conversion from FK to TCPC. METHODS: A retrospective review of medical records for patients who underwent the conversion of FK to TCPC in the period of 1985 to 2016. Significance p < 0,05. RESULTS: Fontan-type operations were performed in 420 patients during this period: TCPC was performed in 320, lateral tunnel technique in 82, and FK in 18. Ten cases from the FK group were elected to conversion to TCPC. All patients submitted to Fontan Conversion were included in this study. In nine patients the indication was due to uncontrolled arrhythmia and in one, due to protein-losing enteropathy. Death was observed in the first two cases. The average intensive care unit (ICU) length of stay (LOS) was 13 days, and the average hospital LOS was 37 days. A functional class by New York Heart Association (NYHA) improvement was observed in 80% of the patients in NYHA I or II. Fifty-seven percent of conversions due to arrhythmias had improvement of arrhythmias; four cases are cured. CONCLUSIONS: The conversion is a complex procedure and requires an experienced tertiary hospital to be performed. The conversion has improved the NYHA functional class despite an unsatisfactory resolution of the arrhythmia.

Outcomes of the Conversion of the Fontan-Kreutzer Operation to a Total Cavopulmonary Connection for the Failing Univentricular Circulation / Resultados da Conversão da Cirurgia de Fontan-Kreutzer para Cavo-Pulmonar Total Devido Falência da Circulação Univentricular

Abstract Background: The Fontan-Kreutzer procedure (FK) was widely performed in the past, but in the long-term generated many complications resulting in univentricular circulation failure. The conversion to total cavopulmonary connection (TCPC) is one of the options for treatment. Objective: To evaluate the results of conversion from FK to TCPC. Methods: A retrospective review of medical records for patients who underwent the conversion of FK to TCPC in the period of 1985 to 2016. Significance p < 0,05. Results: Fontan-type operations were performed in 420 patients during this period: TCPC was performed in 320, lateral tunnel technique in 82, and FK in 18. Ten cases from the FK group were elected to conversion to TCPC. All patients submitted to Fontan Conversion were included in this study. In nine patients the indication was due to uncontrolled arrhythmia and in one, due to protein-losing enteropathy. Death was observed in the first two cases. The average intensive care unit (ICU) length of stay (LOS) was 13 days, and the average hospital LOS was 37 days. A functional class by New York Heart Association (NYHA) improvement was observed in 80% of the patients in NYHA I or II. Fifty-seven percent of conversions due to arrhythmias had improvement of arrhythmias; four cases are cured. Conclusions: The conversion is a complex procedure and requires an experienced tertiary hospital to be performed. The conversion has improved the NYHA functional class despite an unsatisfactory resolution of the arrhythmia.

Resumo Fundamento: O procedimento de Fontan-Kreutzer (FK) foi amplamente realizado no passado, mas a longo prazo gerou muitas complicações, resultando em falha na circulação univentricular. A conversão para conexão cavopulmonar total (CCPT) é uma das opções de tratamento. Objetivo: Avaliar os resultados da conversão de FK para CCPT. Métodos: Revisão retrospectiva de prontuários de pacientes submetidos à conversão de FK para CCPT no período de 1985 a 2016. Significância p < 0,05. Resultados: Operações do tipo Fontan foram realizadas em 420 pacientes durante este período: CCPT foi realizada em 320, técnica de túnel lateral em 82 e FK em 18. Dez casos do grupo FK foram eleitos para conversão em CCPT. Todos os pacientes submetidos à conversão de Fontan foram incluídos neste estudo. Em nove pacientes, a indicação deveu-se a arritmia não controlada e em um devido à enteropatia perdedora de proteínas. A morte foi observada nos dois primeiros casos. O tempo médio de internação na unidade de terapia intensiva (UTI) foi de 13 dias e o tempo médio de internação hospitalar foi de 37 dias. Uma classe funcional pela melhora da New York Heart Association (NYHA) foi observada em 80% dos pacientes em NYHA I ou II. Cinquenta e sete por cento das conversões devido a arritmias tiveram melhora das arritmias; quatro casos foram curados. Conclusões: A conversão é um procedimento complexo e requer que um hospital terciário experiente seja realizado. A conversão melhorou a classe funcional da NYHA, apesar de uma resolução insatisfatória da arritmia.

Anatomical Connections Between the Papillary Muscles and the Ventricular Myocardium: Correlation With QRS Variability of Ventricular Arrhythmias.

BACKGROUND: Papillary muscles (PM) ventricular arrhythmias (VAs) exhibit QRS variability, attributed to anisotropy. ECG inconsistencies such as late precordial transition (TZ) and discordant QRS axis may not be solely explained by anisotropic conduction. We sought to determine the presence of anatomic connections of the PM and correlate them with ECG inconsistencies and ablation results. METHODS: Patients with prior PM VAs catheter ablation (N=33/66 PMs) were prospectively evaluated with cardiac resonance for the presence of muscular connection (PMCs) away from the PM base. Specific ECG characteristics including early (consistent TZ) and late (inconsistent-ITZ) TZ or inconsistent (IQA) or consistent QA QRS axis were correlated with PMCs. RESULTS: Thirty-five PMs exhibited clinical VAs (N=29 posteromedial PM and N=6 anterolateral PM). PM VAs with ITZ and IQA were observed in 11 and 9 PMs, respectively. In total, 41 PMs (62%) exhibited 90 PMCs. Arrhythmogenic PMs (N=35) exhibited higher number of PMCs (72 versus 18; P=0.01). Patients with ITZ and IQA exhibited 100% prevalence of PMCs. Those with consistent TZ and consistent QA showed 40% and 26% prevalence of PMCs, respectively. ITZ and IQA predicted the presence of PMCs with 59% of 28% sensitivity; and 100% of 100% specificity, respectively. Type-specific PMCs were more prevalent in patients with ECG inconsistencies. Those PMs are exhibiting clinical recurrence after ablation presented higher prevalence of PMCs (91% versus 60%; P=0.04). CONCLUSIONS: PMCs are highly prevalent in patients with PM VAs. A direct correlation exists between PM VAs ECG inconsistencies and type-specific PMCs. Patients with ITZ or IQA exhibited PMC 100% prevalence. Recurrence was higher among patients with PMCs.

Cardiac sympathetic denervation for conventional treatment refractory arrhythmias.

Objetivo: La denervación simpática cardiaca izquierda (DSCI) por toracoscopia se ha convertido en una alternativa terapéutica para el manejo de arritmias cardíacas refractarias al tratamiento convencional en pacientes con cardiopatía estructural, principalmente isquémicos, y enfermedades hereditarias asociadas con muerte súbita como el síndrome de QT largo. Generalmente se realiza en quienes manifiestan episodios recurrentes de arritmias ventriculares o incluso tormenta eléctrica a pesar del tratamiento convencional. El objetivo de este estudio es mostrar la experiencia de esta institución con la DSCI en pacientes refractarios al manejo convencional y los resultados derivados de su aplicación. Métodos: Se revisaron los registros de 6 pacientes con antecedente de arritmias ventriculares tratados previamente con medicamentos y en algunos casos con ablación con catéter y la mayoría con desfibrilador automático implantable, que fueron llevados DSCI por toracoscopia video-asistida (VATS). Resultados: La principal enfermedad de base fue la cardiopatía estructural, la indicación más prevalente fue tormenta arrítmica incontrolable, la edad promedio fue de 56 ± 16 años, el 67% de los individuos fueron hombres. Este procedimiento no mostró complicaciones en ninguno de los pacientes y se encontró mejoría sintomática en todos los casos. Se realizó seguimiento por 24 meses; dos pacientes tuvieron recurrencias por taquicardia ventricular lenta sin síntomas severos y uno por fibrilación ventricular. Conclusion: La DSCI por VATS debe considerarse como opción terapéutica para pacientes con arritmias de difícil manejo.

Objective: Cardiac sympathetic denervation (CSD) using video-assisted thoracoscopy is a therapeutic alternative for cardiac arrhythmias refractory to conventional treatment in patients with ventricular structural heart disease, mainly due to ischemia, and in patients with hereditary conditions associated with sudden death such as long QT syndrome. In general, it is performed in cases with recurrent episodes of ventricular tachycardia or electrical storm, in spite of conventional treatment. The objective of this study is to show the experience of this institution with DSCI in refractory patients to conventional management and the results derived from its application. Methods: This was an observational retrospective study. The records of patients with a history of ventricular arrhythmias treated in our center with pharmacological treatment, catheter ablation, or implantation of an implantable cardioverter-defibrillator (ICD), who underwent video-assisted CSD were analyzed and described. Results: A total of six patients were included in the study. Patients with structural heart disease were the most frequent, median age was 56 ± 16 years; 67% were male. The procedure evolved without complications in any of the patients and an overall significant improvement was observed. A 24-month follow-up was conducted; two patients had recurrence episodes presenting as slow ventricular tachycardia without severe symptoms and a third patient presented an episode of ventricular fibrillation aborted by the ICD. Conclusion: Video-assisted CSD should be considered as a treatment option for patients with potentially dangerous arrhythmias that do not respond to conventional treatment, especially in recurrent ventricular tachycardia.