Leptospirosis-Induced Myocarditis and Arrhythmias.

Cardiac manifestations in leptospirosis usually involve atrial arrhythmias, conduction abnormalities, and nonspecific ST-T changes, while left ventricular dysfunction is rare. We present the case of a 45-year-old male without a pre-existing cardiovascular history who developed atrial fibrillation and atrial and ventricular tachycardia, in addition to new-onset cardiomyopathy in the setting of fulminant leptospirosis infection.

Alcoholización de la vena de Marshall: una alternativa rápida, útil y efectiva en el tratamiento del aleteo auricular perimitral. Una descripción de la técnica / Marshall vein alcoholization, fast, useful and effective alternative in the treatment of perimitral atrial flutter. A description of the technique

Resumen Se presenta el caso de un paciente de 68 años con aleteo auricular perimitral recurrente a terapia antiarrítmica en el seguimiento de ablación de venas pulmonares por fibrilación auricular. En este caso no se logra el control de la arritmia a pesar de una aproximación usual; se aplica radiofrecuencia endoepicárdica del istmo mitral. En vista de lo anterior, se decide realizar alcoholización de la vena de Marshall; una técnica rápida, útil y efectiva en el control de esta arritmia. A continuación, se describe el paso a paso con el objetivo de familiarizar a los cardiólogos intervencionistas con esta técnica. A la fecha, el paciente se encuentra en ritmo sinusal y sin recurrencia de la arritmia en el seguimiento.

Abstract The case of a 68-year-old patient with recurrent perimitral atrial flutter to anti-arrhythmic therapy in the follow-up of pulmonary vein ablation due to atrial fibrillation is presented. In our case, arrhythmia control is not achieved despite a usual approach; Endo-epicardial radiofrequency application at the mitral isthmus level. Given the above, it was decided to alcoholize Marshall’s vein; a fast, useful and effective technique in the control of this arrhythmia. Here is a step-by-step guide to familiarize interventional cardiologists with this technique. The patient is in sinus rhythm and without recurrence of the arrhythmia at follow-up.

Use of contact force technology for cardiac arrhythmia ablation in children.

Background: New techniques for cardiac arrhythmia ablation, such as contact force (CF) technology, have emerged recently. These catheters provide information about adequate tissue contact for optimal lesions. In adults, these techniques have shown greater accuracy, reduced arrhythmia recurrence and complications, and higher success rates. However, data on pediatric patients are limited. Objective: The purpose of this study was to describe the experience with arrhythmia ablation using CF catheters in the pediatric population. Methods: A retrospective cross-sectional descriptive study of all patients <18 years old undergoing cardiac 3-dimensional mapping and ablation with CF between March 2016 and June 2022 was performed. Results: A total of 321 patients were included (51.40% male; mean age 12.26 years). The most frequent arrhythmia were supraventricular tachycardia (SVT) mediated by accessory pathways (APs) (atrioventricular reentrant tachycardia in 82.24%, ventricular arrhythmia in 11.21%, atrial tachycardia in 5.92%). Mean procedural time was 2.86 ± 1.2 hours, and average contact used was 14.33g ± 6.88g. The success rate of ablation was 97.82% with a low risk of complications. Conclusion: This is the largest published series of CF technology use in patients <18 years old. In the pediatric population, CF ablation is a safe procedure with high success rates and can be used for most arrhythmic substrates. The most frequent tachycardia observed in this study was SVT mediated by APs. Contact with 14g is safe and yields an excellent outcome in children. The presence of structural heart anomalies and previous ablation procedures decreased the success rate.

Neonatal supraventricular tachyarrhythmias, approach and treatment from pathophysiology / Taquiarritmias supraventriculares neonatales, aproximación y tratamiento desde la fisiopatología.

Supraventricular tachyarrhythmias of the neonatal period are alterations in the heart rhythm that produce an abnormal increase in the heart rate of the newborn, with possible deleterious effects on cardiac output, in a heart with a limited myocardial reserve and that carries a higher risk of fatal outcomes in special populations, such as patients with congenital or acquired heart disease. We present here a review of the literature, with the aim of achieving a timely recognition and management of neonatal supraventricular tachyarrhythmias, based on the diagnostic and therapeutic options available to date.

Las taquiarritmias supraventriculares del período neonatal son alteraciones del ritmo cardíaco que producen un incremento anormal de la frecuencia cardíaca del recién nacido, con posibles efectos deletéreos en el gasto cardíaco, en un corazón con una reserva miocárdica limitada y que supone mayor riesgo de desenlaces letales en poblaciones especiales, como los pacientes con cardiopatías congénitas o adquiridas. Se presenta aquí una revisión de las publicaciones médicas con el objetivo de reconocer y tratar de modo oportuno las taquiarritmias supraventriculares neonatales, con base en las opciones diagnósticas y terapéuticas disponibles hasta el momento.

Epicardial ablation of incessant left atrial appendage tachycardia in a case with tachycardiomyopathy.

Atrial tachycardias originated at the left atrial appendage (LAA) are uncommon; often they are incessant and might induce tachycardiomyopathy, as discussed by Hillock et al. (Heart Rhythm;3(4):467-469, 2006). A case of a 21-year-old woman with incessant atrial tachycardia is presented, refractory to medical therapy, echocardiography showed global dilation with LV ejection fraction of 20%. After two failed endocardial ablations, an epicardial access was attempted. The earliest activation site was located at the tip of the epicardial aspect of the LAA. RFCA was successful at this site. The patient remains asymptomatic during a follow-up of 10 months; the ventricular function was completely recovered after 6 months (LVEF of 50%).

Characterization of atrial arrhythmias in body surface potential mapping: A computational study.

PURPOSE: Atrial tachycardia (AT), flutter (AFL) and fibrillation (AF) are very common cardiac arrhythmias and are driven by localized sources that can be ablation targets. Non-invasive body surface potential mapping (BSPM) can be useful for early diagnosis and ablation planning. We aimed to characterize and differentiate the arrhythmic mechanisms behind AT, AFL and AF from the BSPM perspective using basic features reflecting their electrophysiology. METHODS: 19 simulations of 567-lead BSPMs were used to obtain dominant frequency (DF) maps and estimate the atrial driving frequencies using the highest DF (HDF). Regions with |DF-HDF|≤1Hz were segmented and characterized (size, area); the spatial distribution of the differences |DF-atrialHDFestimate| was qualitatively analyzed. Phase singularity points (SPs) were detected on maps generated with Hilbert transform after band-pass filtering around the HDF (±1Hz). Connected SPs along time (filaments) and their histogram (heatmaps) were used for rotational activity characterization (duration, spatiotemporal stability). Results were reproduced in clinical layouts (252 to 12 leads) and with different rotations and translations of the atria within the torso, and compared with the original 567-lead outcomes using structural similarity index (SSIM) between maps, sensitivity and precision in SP detection and direct feature comparison. Random forest and least-square based algorithms were used to classify the arrhythmias and their mechanisms' location, respectively, based on the obtained features. RESULTS: Frequency and phase analyses revealed distinct behavior between arrhythmias. AT and AFL presented uniform DF maps with low variance, while AF maps were more heterogeneous. Lower differences from the atrial HDF regions correlated with the driver location. Rotational activity was most stable in AFL, followed by AT and AF. Features were robust to lower spatial resolution layouts and modifications in the atrial geometry; DF and heatmaps presented decreasing SSIM along the layouts. The classification of the arrhythmias and their mechanisms' location achieved balanced accuracy of 72.0% and 73.9%, respectively. CONCLUSION: Non-invasive characterization of AT, AFL and AF based on realistic models highlights intrinsic differences between the arrhythmias, enhancing the BSPM utility as an auxiliary clinical tool.

Non-Fluoroscopic Radiofrequency Ablation of Left Atrial Appendage Tachycardia During Early Pregnancy.

Management of symptomatic atrial tachycardia (AT) during pregnancy seems challenging, especially those originating from left atrial appendage (LAA), which easily tend to be incessant and mediate cardiomyopathy. It's contradictory between therapy and pregnancy. In this study, we report a case of a woman who presented with persistent AT, which lead to heart failure, during early pregnancy. She underwent successful catheter ablation using CartoSound and electroanatomic mapping without fluoroscopy. An electrophysiology (EP) study confirmed a focal LAA tachycardia. Soon after, left ventricular function of her heart normalized, and the patient successfully delivered a healthy child.

Non-fluoroscopic radiofrequency ablation of left atrial appendage tachycardia during early pregnancy

Abstract Management of symptomatic atrial tachycardia (AT) during pregnancy seems challenging, especially those originating from left atrial appendage (LAA), which easily tend to be incessant and mediate cardiomyopathy. It's contradictory between therapy and pregnancy. In this study, we report a case of a woman who presented with persistent AT, which lead to heart failure, during early pregnancy. She underwent successful catheter ablation using CartoSound and electroanatomic mapping without fluoroscopy. An electrophysiology (EP) study confirmed a focal LAA tachycardia. Soon after, left ventricular function of her heart normalized, and the patient successfully delivered a healthy child.

Reappraisal and new observations on atrial tachycardia ablated from the non-coronary aortic sinus of Valsalva.

Aims: The clinical characteristics of atrial tachycardias (AT) ablated from the non-coronary aortic sinus (NCS) are thus far described only in small series. We aimed to outline, in a large cohort of patients, the clinical, electrocardiographic, electrophysiological characteristics of this tachycardia. Methods and results: We analysed data pertaining to clinical, electrocardiographic, and electrophysiological characteristics of 43 consecutive patients from an overall cohort of 441 with AT who were successfully ablated from the NCS. The tachycardias ablated from the NCS were paroxysmal (98%) and adenosine sensitive (35/35). The patients were aged 54.6 ± 12.4 years, showing female preponderance (74%). No P wave pattern was predictive of the location of ablation. Electrophysiological findings suggested a possible micro-reentrant mechanism. During tachycardia, atrial electrograms recorded in the NCS preceded the A in the His region by 10.9 ± 7.4 ms. Fractionated atrial electrograms were noted at the site of ablation in 42 patients during the tachycardia. Radiofrequency ablation terminated the tachycardia within 5 s in 88%, with thermal automaticity seen only in 3 patients. The site of ablation at the base of the NCS was adjacent to the presumed site of the retroaortic node, a remnant of the initial atrio-ventricular canal musculature. Conclusions: AT ablated from the NCS is a paroxysmal arrhythmia in middle-aged women, with distinct electrocardiographic and electrophysiological characteristics. We suspect the retroaortic node to be involved in the tachycardia circuit.

Simplified progressive approach for the ablation of scar related atrial macroreentrant tachycardias.

INTRODUCTION: Radiofrequency ablation of scar related right atrial flutter is challenging. Long procedures, prolonged fluoroscopic times and high percentages of recurrences are of concern. We present a simple and progressive approach based on a single electroanatomic map of the right atrium. METHODS: Twenty-two consecutive patients with atrial flutter and history of cardiac surgery were included. An electrophysiologic study was performed to define localization (left or right) and cavo-tricuspid isthmus participation using entrainment mapping. After a critical isthmus was localized, ablation was performed with an external irrigated tip catheter with a power limit of 30 W. Potential ablation sites were confirmed by entrainment. RESULTS: The predominant cardiopathy was atrial septal defect. All arrhythmias were localized in the right atrium; mean cycle length of the clinical flutter was 274 ± 31 ms. Only 40% had cavo-tricuspid isthmus participation. None of the patients with successful ablation had recurrences after 13 ± 9.4 months of follow-up. CONCLUSIONS: A progressive approach with only one activation/voltage CARTO(®) map of the atrium and ablation of all potential circuits is a highly effective method for ablating scar related macroreentrant atrial arrhythmias.

Cardiomiopatía inducida por taquicardia en niños y adolescentes / Tachycardia-induced cardiomyopathy in children and adolescents

Introducción. La cardiomiopatía dilatada idiopática es la forma más común de cardiomiopatía en niños; sin embargo, ocasionalmente son identificadas causas potencialmente reversibles. Entre estas existe un grupo de pacientes con manifestaciones de insuficiencia cardiaca y taquicardia persistente que representan una forma de cardiomiopatía no familiar adquirida conocida como cardiomiopatía inducida por taquicardia o taquicardiomiopatía, que es reversible con el tratamiento efectivo de la taquicardia. Estos pacientes pueden ser mal diagnosticados y tratados de forma inapropiada. El diagnóstico frecuentemente es tardío, por lo que debe sospecharse en pacientes con insuficiencia cardiaca y taquicardia persistente sin causa aparente. Casos clínicos. Se describen seis casos de pacientes pediátricos de 6 a 16 años de edad (media 12 ± 4 años) que se presentaron con manifestaciones clínicas de insuficiencia cardiaca. Tuvieron seguimiento por una forma de cardiomiopatía dilatada en los que se documentaron diferentes mecanismos de taquiarritmia persistente como la causa. El tratamiento apropiado -mediante ablación con catéter- condujo a la recuperación de la función ventricular. Conclusiones. Es importante el reconocimiento de la cardiomiopatía inducida por taquiarritmia en pediatría. También es necesario un diagnóstico oportuno así como un tratamiento eficaz, ya que la cardiomiopatía inducida por taquicardia es una causa reversible de insuficiencia cardiaca.

Background. Idiopathic dilated cardiomyopathy is the most common form of cardiomyopathy in children; however, potentially reversible causes may occasionally be identified. Among these a group of patients with symptoms of congestive heart failure and persistent tachycardia representing a form of nonfamilial acquired cardiomyopathy known as tachycardia-induced cardiomyopathy or tachycardiomyopathy. This is a reversible condition with effective treatment of tachycardia. These patients may be misdiagnosed, potentially leading to inappropriate treatment. Diagnosis is often late and always should be suspected in patients with congestive heart failure and unexplained persistent tachycardia. Case reports. We describe six pediatric patients (mean age 12 ±4 years old, range 6-16 years). Patients presented with clinical manifestations of heart failure followed by dilated cardiomyopathy. Different mechanisms of persistent tachycardia were documented as the cause and total recovery was achieved of ventricular function after successful treatment of tachycardia by catheter ablation. Conclusions. The recognition of tachyarrhythmia-induced cardiomyopathy in pediatric patients is important. Opportune diagnosis and effective treatment are necessary because tachycardia-induced cardiomyopathy is a reversible cause of heart failure.

Taquicardia auricular focal incesante originada en la orejuela derecha: riesgo de taquicardiomiopatía: rol de la ablación por radiofrecuencia / Incessant focal atrial tachycardia arising from the right appendage: risk of tachycardia mediated cardiomyopathy: role of the radiofrequency ablation

Las taquicardias auriculares focales pueden originarse en distintas regiones de la aurícula derecha, incluidos la crista terminalis, el anillo tricuspídeo, el septum interauricular y la orejuela derecha. Las originadas en esta última región anatómica se caracterizan por presentar un comportamiento incesante y mala respuesta al tratamiento farmacológico antiarrítmico, con desarrollo de taquicardiomiopatía; su tratamiento de elección es la ablación por radiofrecuencia.Presentamos el caso de una infante de 36 meses de edad, con taquicardiomiopatía secundaria a taquicardia auricular incesante de orejuela derecha, a quien se le realizó ablación por radiofrecuencia.

Focal atrial tachycardias originate from different anatomic regions of the right atrium including the crista terminalis, the coronary sinus ostium, the tricuspid annulus, the interatrial septum and the right atrial appendage. The latter are characterized by being incessant and presenting poor response to antiarrhythmic treatment. They frequently evolve into tachycardiomyopathy and radiofrequency ablation is the treatment of choice. We present the case of a 36 month old girl with tachycardiomyopathy as a result of an incessant atrial tachycardia originated in the right atrial appendage. Patient underwent radiofrequency ablation.

Taquicardia auricular focal incesante originada en la orejuela derecha: riesgo de taquicardiomiopatía: rol de la ablación por radiofrecuencia / Incessant focal atrial tachycardia arising from the right appendage: risk of tachycardia mediated cardiomyopathy: role of the radiofrequency ablation

Las taquicardias auriculares focales pueden originarse en distintas regiones de la aurícula derecha, incluidos la crista terminalis, el anillo tricuspídeo, el septum interauricular y la orejuela derecha. Las originadas en esta última región anatómica se caracterizan por presentar un comportamiento incesante y mala respuesta al tratamiento farmacológico antiarrítmico, con desarrollo de taquicardiomiopatía; su tratamiento de elección es la ablación por radiofrecuencia.Presentamos el caso de una infante de 36 meses de edad, con taquicardiomiopatía secundaria a taquicardia auricular incesante de orejuela derecha, a quien se le realizó ablación por radiofrecuencia.(AU)

Focal atrial tachycardias originate from different anatomic regions of the right atrium including the crista terminalis, the coronary sinus ostium, the tricuspid annulus, the interatrial septum and the right atrial appendage. The latter are characterized by being incessant and presenting poor response to antiarrhythmic treatment. They frequently evolve into tachycardiomyopathy and radiofrequency ablation is the treatment of choice. We present the case of a 36 month old girl with tachycardiomyopathy as a result of an incessant atrial tachycardia originated in the right atrial appendage. Patient underwent radiofrequency ablation.(AU)

Taquicardias supraventriculares incessantes: estudo retrospectivo de treze pacientes / Incessant Supraventricular Tachycardias. Retrospective Study of Thirteen Patients

PURPOSE--To evaluate, retrospectively, the main clinical findings observed in patients with incessant supraventricular tachycardias. METHODS--Data from 13 patients were analyzed, 8 men and 5 women, mean age 24 +/- 19 years. All patients underwent to periodic clinical evaluation with serial ECG, Holter, echocardiography and in three patients an electrophysiological study. From these diagnostic methods it was possible to define the site of origin of the tachycardias, the autonomic influences upon them, the progressive hemodynamic compromise leading to tachycardiomyopathy and the drug response. RESULTS--In 9 patients the tachycardias had an atrial origin, in three an accessory pathway was involved and in one patient an atypical nodal reentry was identified. Clear autonomic influences upon the rate of the tachycardias were noted in the majority of patients, based on Holter recordings. Forty-six percent of the population developed progressive contractile deficit, contributing in one patient to his death. Drug failure was observed in 62 per cent of patients, even with the use of three antiarrhythmic drugs in a row. The large majority of the patients were still asymptomatic by the time of the retrospective data. CONCLUSION--The most relevant clinical aspects are the progressive development of tachycardiomyopathy, associated with refractoriness to drug therapy and indicate in this population the approach to be undertaken

Objetivo - Avaliar de forma retrospectiva, os achados clínicos principais observados em pacientes com taquicardias supraventriculares incessantes Métodos - Foram analisados os dados de 13 pacientes (8 masculinos) com idade média de 24±19 anos. Todos os pacientes foram submetidos a avaliação clínica periódica, com eletrocardiogramas, Holter e ecocardiogramas seriados. Três pacientes foram submetidos a estudo eletrofisiológico. A partir dos exames complementares definiram-se a origem das taquicardias, as influências autonomicas sobre as mesmas, as repercussões hemodinâmicas progressivas, levando a quadros de taquicardiomiopatias e a resposta medicamentosa. Resultados - Em 9 pacientes as taquicardias tinham origem nos átrios, em 3 pacientes ocorriam pela presença de vias anômalas e em um paciente era conseqüente a forma atípica de reentrada nodal. Em todos os pacientes pode-se detectar, a partir do Holter, nítidas influências autonômicas sobre a freqüencia das taquicardias. Ocorreu em 46% da população, déficit contrátil progressivo, colaborando em um paciente para a sua morte. Resistência medicamentosa foi observada em 62% dos pacientes, com o uso de até três antiarrítmicos. A grande maioria dos pacientes manteve-se assintomática até o período de levantamento dos dados do presente estudo. Conclusão - Os dados clínicos mais relevantes referem-se a presença de quadro progressivo de taquicardiomiopatia, associado a resistência medicamentosa para controle dos surtos e definem nessa população a conduta clínica a ser adotada