Outcomes of ventricular tachycardia ablation in patients with ischemic and non-ischemic cardiomyopathy: A propensity-score matched analysis.

INTRODUCTION AND OBJECTIVES: Catheter ablation (CA) is effective in the treatment of ventricular tachycardia (VT). Although some observational data suggest patients with non-ischemic cardiomyopathy (NICM) have less favorable outcomes when compared to those with an ischemic etiology (ICM), direct comparisons are rarely reported. We aimed to compare the outcomes of VT ablation in a propensity-score matched population of ICM or NICM patients. METHODS: Single-center retrospective study of consecutive patients undergoing VT ablation from 2012 to 2023. A propensity score (PS) was used to match ICM and NICM patients in a 1:1 fashion according to age, sex, left ventricular ejection fraction (LVEF), NYHA class, electrical storm (ES) at presentation, and previous endocardial ablation. The outcomes of interest were VT-free survival and all-cause mortality. RESULTS: The PS yielded two groups of 71 patients each (mean age 63±10 years, 92% male, mean LVEF 35±10%, 36% with ES at presentation, and 23% with previous ablation), well matched for baseline characteristics. During a median follow-up of 2.3 (interquartile range IQR 1.3-3.8) years, patients with NICM had a significantly lower VT-free survival (53.5% vs. 69.0%, log-rank p=0.037), although there were no differences regarding all-cause mortality (22.5% vs. 16.9%, log-rank p=0.245). Multivariate analysis identified NICM (HR 2.34 [95% CI 1.32-4.14], p=0.004), NYHA class III/IV (HR 2.11 [95% CI 1.11-4.04], p=0.024), and chronic kidney disease (HR 2.23 [95% CI 1.25-3.96], p=0.006), as independent predictors of VT recurrence. CONCLUSION: Non-ischemic cardiomyopathy patients were at increased risk of VT recurrence after ablation, although long-term mortality did not differ.

Long-term prognosis of idiopathic ventricular fibrillation: An eighteen-year experience from a tertiary center.

INTRODUCTION AND OBJECTIVES: Idiopathic ventricular fibrillation (IVF) is diagnosed in patients who survive sudden cardiac arrest (SCA), preferably with documented ventricular fibrillation (VF), without any identifiable structural or electrical abnormality. Current evidence provides limited guidance on the diagnosis and follow-up of these patients. Our aim was to assess the clinical outcomes of survivors of an aborted SCA attributed to IVF. METHODS: We retrospectively collected clinical data from all patients who survived SCA and implanted a cardiac defibrillator (ICD) between 2005 and 2023. RESULTS: A total of 38 patients, 36.8% female, with a mean age of 44±14 years old were included. Median follow-up time was 8.7 years (interquartile range (IQR) 4.7-14.7 years). All patients underwent a comprehensive diagnostic evaluation that excluded structural and coronary disease. During follow-up, underlying diagnoses were established in 34.2% of the whole cohort. Genetic testing, performed in 37.2%, revealed underlying diagnoses in 57.1% of those tested, compared to only 26.3% of patients who did not undergo genetic testing [p=0.035, OR=5.1 (95% confidence interval (CI) 1.2-21.5)]. Mortality was 10.5% (due to non-arrhythmic causes) and 36.8% patients received appropriate therapies with a median time to first ICD therapy of 39 [5.4-47.3] months. CONCLUSION(S): Etiological diagnosis and recurrence prediction in patients with IVF remains challenging, even with extensive diagnostic evaluation and long-term follow-up. In our study, genetic testing enhanced diagnostic yield. Consistent with previous findings, our cohort experienced a notable arrhythmic recurrence, with no cardiac deaths, underlining the pivotal role of ICD implantation in these patients.

Bloqueo del ganglio estrellado como tratamiento de la tormenta arrítmica: estudio observacional / Stellate ganglion block as a treatment for arrhythmic storm: an observational study

Introducción: La tormenta arrítmica (TA) es una situación de emergencia potencialmente letal, con una elevada tasa de mortalidad. Cuando el tratamiento convencional agudo es inefectivo, el bloqueo del ganglio estrellado puede ayudar a controlar la arritmia, aportando un bloqueo simpático cervicotorácico visceral. El objetivo de este estudio es valorar la efectividad y seguridad de los bloqueos del ganglio estrellado (BGE) para el tratamiento de la TA refractaria. Método: Seguimiento de una cohorte de pacientes con TA refractaria que cumplieron los criterios para la realización de BGE. Dicho bloqueo fue ecoguiado al nivel de C6, utilizando un anestésico y un esteroide, de manera unilateral izquierda en primer lugar, y bilateral de no existir respuesta, realizándose posteriormente ablación mediante radiofrecuencia (RFC) guiada por fluoroscopio en C7 de no existir respuesta favorable, sino recidiva subsiguiente. Resultados: Se incluyeron siete pacientes, con una tasa de mortalidad durante el ingreso de 14,29%. Cuatro pacientes recibieron bloqueos unilaterales del ganglio estrellado, y en tres pacientes se realizaron bloqueos bilaterales. En seis de ellos se aplicó ablación, y uno de ellos tenía implantado un cardioversor-desfibrilador. La TA fue controlada temporalmente, más allá del efecto del anestésico local en todos los pacientes. Tres de ellos recibieron ablación por RFC, y dos simpatectomías torácicas quirúrgicas. El único efecto secundario fue el síndrome de Horner, que se observó en todos los casos tras realizar el bloqueo del ganglio estrellado con anestésico local. Dos pacientes murieron tras recibir el alta, y cuatro siguen en sus casas, tres de ellos sin haber sido ingresados a causa de episodios ventriculares durante más de dos años. Conclusión: El bloqueo ecoguiado del ganglio estrellado es una técnica efectiva y segura para el tratamiento de la TA refractaria, como complemento del tratamiento cardiológico habitual.(AU)

Introduction: Arrhythmic storm is a life-threatening emergency with a high mortality rate. When acute conventional treatment is ineffective, a stellate ganglion block can contribute to the control of the arrhythmia by providing a visceral cervicothoracic sympathetic block. The objective of the study is to assess the effectiveness and safety of stellate ganglion blocks for the treatment of refractory arrhythmic storm. Method: Follow-up of a cohort of patients with refractory arrhythmic storm that met the criteria for performing stellate ganglion blocks. The block was ultrasound-guided at C6-level using local anaesthetic and a steroid, left unilateral first, bilateral if no response, and followed by fluoroscopy-guided radiofrequency ablation at C7 if there was a favourable response but subsequent relapse. Results: Seven patients were included, with a mortality rate during admission of 14.29%. Four patients received unilateral and three bilateral stellate ganglion blocks. Six were ablated and one of them had an implanted cardioverter-defibrillator. Arrhythmic storm was controlled temporarily beyond the effect of the local anaesthetic in all patients. Three underwent radiofrequency ablation and two underwent surgical thoracic sympathectomy. The only side effect was Horner's syndrome, which was observed in all cases after administering a stellate ganglion block with local anaesthetic. Two died after discharge and four are still at home, three of them without further admission due to ventricular events for more than two years. Conclusion: An ultrasound-guided stellate ganglion block is an effective and safe technique in the treatment of refractory arrhythmic storm as a complement to the usual cardiological treatment.(AU)

Stellate ganglion block for the management of electrical storm: An observational study.

INTRODUCTION: Electrical storm is a life-threatening emergency with a high mortality rate. When acute conventional treatment is ineffective, stellate ganglion block can help control arrhythmia by providing a visceral cervicothoracic sympathetic block. The objective of this study is to assess the effectiveness and safety of stellate ganglion block in the management of refractory arrhythmic storm. METHOD: Follow-up of a cohort of patients with refractory electrical storm that met the criteria for performing stellate ganglion block. The block was ultrasound-guided at C6 using local anaesthetic and a steroid - left unilateral first, bilateral if no response, followed by fluoroscopy-guided radiofrequency ablation at C7 if there was a favourable response but subsequent relapse. RESULTS: Seven patients were included. The in-hospital mortality rate was 14.29%. Four patients received unilateral and 3 bilateral stellate ganglion block. Six were ablated and 1 received an implantable cardioverter-defibrillator. Electrical storm was controlled temporarily beyond the effect of the local anaesthetic in all patients. Three patients underwent radiofrequency ablation and 2 underwent surgical thoracic sympathectomy. The only side effect was Horner's syndrome, which was observed in all cases after administering a stellate ganglion block with local anaesthetic. Two patients died after discharge and 4 are alive at the time of writing, 3 of them have not been re-admitted for ventricular events for more than 2 years. CONCLUSION: Ultrasound-guided stellate ganglion block is an effective and safe complement to standard cardiological treatment of refractory electrical storm.

Taquicardia ventricular polimórfica tipo torsadess de pointes secundaria a estimulación por marcapasos / Polymorphic ventricular taquicardia "torsades de pointes" associated to abnormal pacemaker stimulation

La taquicardia ventricular polimórfica se origina en los ventrículos, cuyos complejos QRS son de morfología, amplitud y dirección variable, con frecuencias que oscilan entre 200 y 250 lpm, pudiendo ser autolimitadas o degenerar en una fibrilación ventricular. La TdP es un tipo de taquicardia ventricular polimórfica caracterizada por complejos con un eje eléctrico que gira alrededor de la línea isoeléctrica y que está asociada a QT largo. Se presenta el caso de una paciente portadora de marcapaso que presenta episodios de taquicardia ventricular polimórfica, con una morfología típica de TdP, sin documentación de QT prolongado previo ni actual, generada por la estimulación ventricular sobre onda T, de forma accidental por desplazamiento del electrodo auricular a Ventrículo Derecho (VD).

Polymorphic ventricular tachycardia is a tachycardia originating in the ventricles, where the QRS complexes have variable morphology, amplitude, and direction, with frequencies ranging between 200 and 250 bpm; it may be self-limited or degenerate into ventricular fibrillation. Torsades de Pointes (TdP) is a type of polymorphic ventricular tachycardia characterized by complexes with an electrical axis that rotates around the isoelectric line and that is associated with long QT interval. We present the case of a patient with a pacemaker who presents episodes of polymorphic ventricular tachycardia, with a typical morphology of TdP, without documentation of previous or current prolonged QT, generated by ventricular stimulation on the T wave, accidentally due to displacement of the atrial electrode to the Right Ventricle (RV).

Taquicardia ventricular polimorfa en un paciente con fibrilación auricular de respuesta ventricular rápida. Reporte de Caso

Las taquicardiomiopatías por su fisiopatología de pérdida del acoplamiento miocárdico, proporcionan el sustrato adecuado para la disfunción ventricular que dan paso a arritmias ventriculares letales. Se reporta el caso de una paciente femenina de 75 años, sin antecedentes personales patológicos conocidos, que acude con historia de disnea de medianos esfuerzos que rápidamente progresa a disnea de pequeños esfuerzos asociado a palpitaciones. Posteriormente desarrolla taquicardia ventricular polimorfa no sostenida durante su estancia hospitalaria por lo que fue necesario realizar en dos ocasiones maniobras de reanimación con cardioversión eléctrica y el restablecimiento del ritmo sinusal con fármacos para mejorar la función del ventrículo izquierdo. (provisto por Infomedic International)

  Tachycardiomyopathies due to their pathophysiology of loss of myocardial coupling, provide the adequate substrate for ventricular dysfunction that leads to lethal ventricular arrhythmias. The following is the case of a 75-year-old female patient, with no known history, who presented with symptoms of advanced heart failure and atrial fibrillation, who later developed non-sustained polimorphic ventricular tachycardia during her hospital stay for which it was necessary to perform resuscitation maneuvers with electrical cardioversion on two separate occasions and the restoration of sinus rhythm with drugs to improve left ventricular function. (provided by Infomedic International)

Ressonância Magnética Cardíaca como Ferramenta Diagnóstica Etiológica em Pacientes Recuperados de Morte Súbita Cardíaca ou Arritmias Ventriculares Instáveis / Cardiac Magnetic Resonance as an Etiological Diagnosis Tool in Recovered Sudden Cardiac Death or Unstable Ventricular Arrhythmia Patients

Resumo Fundamento A ressonância magnética cardíaca (RMC) tem relevância diagnóstica crescente em sobreviventes de morte súbita cardíaca (MSC) ou arritmia ventricular instável (AVI) em países desenvolvidos. Objetivo Procuramos avaliar retrospectivamente o papel adicional da RMC em um país em desenvolvimento com poucos recursos disponíveis e que pode direcionar um uso mais eficaz desses recursos. Métodos Foram incluídos sobreviventes de MSC ou AVI admitidos entre 2009 e 2019 em uma instituição acadêmica terciária após a realização de RMC. Dados demográficos, clínicos e laboratoriais foram coletados dos prontuários. Imagens e laudos de RMC foram analisados e o impacto disso no diagnóstico etiológico final foi afirmado. Realizou-se análise descritiva e definiu-se p<0,05 como significativo. Resultados Sessenta e quatro pacientes, 54,9±15,4 anos, sendo 42 (71,9%) do sexo masculino. A maioria dos eventos (81,3%) foi extra-hospitalar e a taquicardia ventricular foi o ritmo mais comum. Medicamentos cardiovasculares foram utilizados anteriormente por 55 pacientes, sendo os betabloqueadores os medicamentos mais utilizados (37,5%). O eletrocardiograma apresentava áreas elétricas inativas em 21,9% e todos apresentavam fibrose na RMC. A média da fração de ejeção do ventrículo esquerdo (FEVE) foi de 44±14%, com 60,9% ≤50% e apenas 29,7% ≤35%. Identificou-se realce tardio com gadolínio em 71,9%, com padrão transmural em 43,8%. A miocardiopatia chagásica foi a etiologia mais comum (28,1%), seguida da miocardiopatia isquêmica (17,2%). Entre 26 sem etiologia previamente identificada, foi possível definir com RMC (15 pacientes - 57%). Conclusão De acordo com estudos anteriores em países desenvolvidos, a RMC foi capaz de aumentar o diagnóstico etiológico e identificar o substrato arritmogênico, permitindo melhor atendimento em metade dos pacientes subdiagnosticados.

Abstract Background Cardiac magnetic resonance (CMR) has an increasing diagnostic relevance in survivors of sudden cardiac death (SCD) or unstable ventricular arrhythmia (UVA) in developed countries. Objective To evaluate retrospectively the additional role of CMR in a developing country where few resources are available, and should be used more effectively. Methods The study included SCD or UVA survivors admitted between 2009 and 2019 at a tertiary academic institution referred to CMR. Demographic, clinical, and laboratory data were collected from the medical records. CMR images and reports were reviewed and their impact on the final etiological diagnosis was determined. A descriptive analysis was performed and p<0.05 established as significant. Results Sixty-four patients, 54.9±15.4 years old, and 42 (71.9%) males. Most events (81.3%) were out of the hospital and ventricular tachycardia was the most common rhythm. Cardiovascular medications were previously used by 55 patients, and beta-blockers were the most used medications (37.5%). Electrocardiogram had electrical inactive areas in 21.9% and all of them had fibrosis at CMR. Mean left ventricular ejection fraction (LVEF) was 44±14%, with 60.9% ≤50% and only 29.7% ≤35%. Late gadolinium enhancement was identified in 71.9%, with a transmural pattern in 43.8%. Chagas cardiomyopathy was the most common etiology (28.1%), followed by ischemic cardiomyopathy (17.2%). Among 26 without a previously identified etiology, CMR could define it (15 patients - 57%). Conclusion In accordance with previous studies in developed countries, CMR was capable of increasing etiological diagnosis and identifying the arrhythmogenic substrate, allowing better care in half of the underdiagnosed patients.

Teste de Limiar de Desfibrilação e Seguimento a Longo Prazo de Pacientes com Cardiopatia Crônica da Doença de Chagas / Defibrillation Threshold Testing and Long-term Follow-up in Chagas Disease

Resumo Fundamento A morte súbita cardíaca (MSC) é a causa mais comum de óbito na cardiomiopatia crônica da doença de Chagas (CCDC). Visto que muitos pacientes com CCDC que são candidatos a receber um cardioversor desfibrilador implantável (CDI) atendem a critérios que sugerem alto risco de apresentarem limiares de desfibrilação elevados, sugere-se realizar um teste de limite de desfibrilação (LDF). Objetivos Investigamos o uso do teste de LDF em pacientes com CCDC, com enfoque nos óbitos relacionados ao implante do CDI e na ocorrência de eventos arrítmicos e o tratamento oferecido durante o seguimento de longo prazo. Métodos Avaliações retrospectivas de 133 pacientes com CCDC que receberam CDI, principalmente para prevenção secundária. Foram coletados dados demográficos, clínicos e laboratoriais, escore de Rassi e dados do teste de LDF. Adotou-se p<0,05 como estatisticamente significativo. Resultados A média de idade foi 61±13 anos, e 72% da amostra era do sexo masculino. A fração de ejeção basal do ventrículo esquerdo foi 40±15%, e o escore de Rassi médio foi 10±4 pontos. Não ocorreram óbitos durante o teste de LDF, e não foram documentadas falhas do CDI. Foi identificada relação entre escore de Rassi basal mais elevado e LDFs mais elevados (ANOVA =0,007). O tempo médio até o primeiro choque foi de 474±628 dias, mas a aplicação de choque foi necessária em apenas 28 (35%) pacientes com TV, visto que a maioria dos casos se resolveu espontaneamente ou através da programação de ATP. Após seguimento clínico de 1728±1189 dias, em média, ocorreram 43 óbitos, relacionados principalmente a insuficiência cardíaca progressiva e sepse. Conclusões Um teste de LDF de rotina pode não ser necessário para pacientes com CCDCs que receberam CDI para prevenção secundária. LDFs elevados parecem ser incomuns e podem estar relacionados a escore de Rassi elevado.

Abstract Background Sudden cardiac death is the most common cause of death in chronic Chagas cardiomyopathy (CCC). Because most CCC patients who are candidates for implantable cardioverter-defibrillators (ICD) meet criteria for high defibrillation threshold values, a defibrillator threshold test (DTT) is suggested. Objectives We investigated the use of DTT in CCC patients, focusing on deaths related to ICD and arrhythmic events, as well as treatment during long-term follow-up. Methods We retrospectively evaluated 133 CCC patients who received an ICD mainly for secondary prevention. Demographic, clinical, laboratory data, Rassi score, and DTT data were collected, with p < 0.05 considered significant. Results The mean patient age was 61 (SD, 13) years and 72% were men. The baseline left ventricular ejection fraction was 40 (SD, 15%) and the mean Rassi score was 10 (SD, 4). No deaths occurred during DTT and no ICD failures were documented. There was a relationship between higher baseline Rassi scores and higher DTT scores (ANOVA = 0.007). The mean time to first shock was 474 (SD, 628) days, although shock was only necessary for 28 (35%) patients with ventricular tachycardia, since most cases resolved spontaneously or through antitachycardia pacing. After a mean clinical follow-up of 1728 (SD, 1189) days, 43 deaths occurred, mainly related to progressive heart failure and sepsis. Conclusions A routine DTT may not be necessary for CCC patients who receive an ICD for secondary prevention. High DTT values seem to be unusual and may be related to high Rassi scores.

Severe primary hypothyroidism presenting as polymorphic ventricular tachycardia / Hipotiroidismo primario grave que se presenta como taquicardia ventricular polimórfica

Abstract Introduction: Hypothyroidism may have various cardiovascular manifestations due to morphological, functional and electrical alterations in the heart. The usual electrocardiographic findings being sinus bradycardia, low voltage complexes, and slowed intraventricular conduction. Hypothyroidism manifesting as polymorphic ventricular tachycardia has only been reported in a few case reports. Clinical case. A 60-year-old lady presented to us in the emergency department in an unresponsive and unconscious state and electrocardiogram showed a polymorphic ventricular tachycardia. After initial resuscitation with direct current cardioversion and supportive care, she found to have severe hypothyroidism and responded well to thyroid replacement therapy. Conclusion. Polymorphic ventricular tachycardia is a life threatening emergency that can have various etiologies. Polymorphic ventricular tachycardia secondary to primary hypothyroidism is a rare presentation but it is treatable and reversible with thyroid replacement therapy. In patients presenting with QT interval prolongation and ventricular tachycardia, hypothyroidism should be one of the differential diagnosis.

Resumen Introducción: El hipotiroidismo puede presentar diferentes manifestaciones cardiovasculares dadas por alteraciones morfológicas, funcionales y eléctricas en el corazón, siendo los hallazgos electrocardiográficos usuales son la bradicardia sinusal, los complejos de bajo voltaje y la conducción intraventricular lenta. El hipotiroidismo manifestado como taquicardia ventricular polimórfica solo se ha descrito en unos pocos reportes de caso. Caso clínico: Se trata de una mujer de 60 años que acudió que acurdió al servicio de urgencias en un estado inconsciente y sin respuesta a estímulos, y el electrocardiograma reveló taquicardia ventricular polimórfica. Luego de la reanimación inicial con cardioversión con corriente directa y tratamiento sintomático se le encontró un hipotiroidismo grave, el cual se trató con terapia de reemplazo con hormona tiroidea. y se obtuvo una buena respuesta Conclusión. La taquicardia ventricular polimórfica es una emergencia vital que puede tener varias etiologías. La taquicardia ventricular polimórfica secundaria a un hipotiroidismo primario es una presentación poco común, pero es tratable y reversible con la terapia de reemplazo con hormona tiroidea. En los pacientes que presentan una prolongación del intervalo QT y taquicardia ventricular, es pertinente incluir el hipotiroidismo en el diagnóstico diferencial.

Taquicardia ventricular asociada a mutación en el gen de ankirina B / Ventricular tachycardia associated to a mutation in the ankyrin B gen

Resumen Se presenta el caso de una mujer de 14 años, con taquicardiomiopatía secundaria a taquicardia ventricular. Se evidenció la presencia de una variante de significado incierto en el gen ANK2, por lo que se consideró un posible síndrome de ankirina B. La paciente fue tratada con éxito a través de ablación con radiofrecuencia. Tras dicho procedimiento, tuvo recuperación completa de su función ventricular izquierda y resolución de los complejos ventriculares prematuros y los episodios de taquicardia ventricular.

Abstract We report a case of a 14-year-old with tachycardiomyopathy due to ventricular tachycardia. A variant of uncertain significance of the ANK2 gene was identified, which is suggestive of a possible ankyrin-B syndrome. The patient underwent a successful radiofrequency ablation. After the procedure, the patient completely recovered her left ventricular function and there was resolution of the premature ventricular complexes and ventricular tachycardia.

Idiopathic left fascicular ventricular tachycardia in children and adolescents.

BACKGROUND: Idiopathic ventricular tachycardia (VT) in children with structurally normal hearts is generally unrelated to the risk of sudden arrhythmic death. Still, it may be associated with deterioration in the quality of life. VT involving the fascicular conduction system is the most typical form of idiopathic left VT. In this retrospective study, we describe the experience of the clinical presentation, catheter ablation, and long-term follow-up of left fascicular VT in children. METHODS: An electrophysiological study was performed on consecutive children at a single tertiary center. Clinical fascicular left VT was induced by programmed stimulation, and catheter ablation was guided searching for Purkinje potentials. RESULTS: We included 18 patients (0.8 patients/year): 14 (77.8%) males and four females. The mean age of the first VT episode was 8.5 ± 5 years. Intravenous verapamil administration was effective for paroxysmal fascicular VT but not for prevention of recurrences. The mean age at the time of catheter ablation was 11.1 ± 3.8 years (8 months-16 years). The mean weight was 36.8 ± 16.4 kg (8.7-58 kg). A 100% success rate was observed with catheter ablation after repeated procedures without major complications. Mean follow-up was 2.0 ± 1.2 years (1.0-4.0 years, median 1.5), with permanent success in all patients and no antiarrhythmic drug administration. CONCLUSIONS: Fascicular VT has an adverse clinical course in children. In most cases, this condition is drug refractory. Catheter ablation is successful and safe treatment and should represent the first-line approach in symptomatic children.

INTRODUCCIÓN: La taquicardia ventricular (TV) idiopática en niños con corazón estructuralmente normal generalmente no se relaciona con el riesgo de muerte súbita arrítmica, pero puede asociarse con deterioro de la calidad de vida. La TV que involucra el sistema de conducción fascicular es la forma más común de TV izquierda idiopática. En este estudio retrospectivo se describe la experiencia de presentación clínica, ablación con catéter y seguimiento a largo plazo de TV fascicular en niños. MÉTODOS: Se llevó a cabo un estudio electrofisiológico en niños consecutivos en un centro terciario. La TV fascicular clínica se indujo mediante la estimulación programada y la ablación con catéter fue guiada buscando el registro de potenciales de Purkinje. RESULTADOS: Se incluyeron 18 pacientes (0.8 pacientes/año): 14 (77.8%) de sexo masculino y cuatro de sexo femenino. La media de edad a la cual ocurrió el primer episodio fue de 8.5 ± 5 años. La administración intravenosa de verapamilo fue eficaz para la TV fascicular paroxística, pero no para prevención de recurrencias. La media de edad de la ablación con catéter fue de 11.1 ± 3.8 años (8 meses-16 años). La media del peso fue 36.8 ± 16.4 kg (8.7-58 kg). Se observó el 100% de éxito con la ablación con catéter después de procedimientos repetidos sin complicaciones mayores. La media de seguimiento fue de 2.0 ± 1.2 años (1.0-4.0, mediana de 1.5 años) con éxito permanente en todos los pacientes y sin administración de fármacos antiarrítmicos. CONCLUSIONES: En niños, el curso clínico de la TV fascicular es adverso. Además, en la mayoría de los casos, esta condición es refractaria a fármacos. La ablación con catéter resulta exitosa y segura y debe representar el abordaje de primera línea en niños sintomáticos.

Outcome of ventricular tachycardia catheter ablation in ischemic heart disease patients using a high-density mapping substrate-based approach: A prospective cohort study.

INTRODUCTION AND OBJECTIVE: Radiofrequency catheter ablation (RCA) for ventricular tachycardia (VT) in patients with ischemic heart disease (IHD) is associated with a reduced risk of VT storm and implantable cardioverter defibrillator (ICD) shocks. We aim to report the outcome after a single RCA procedure for VT in patients with IHD using a high-density substrate-based approach. METHODS: We conducted a prospective, observational, single-center and single-arm study involving patients with IHD, referred for RCA procedure for VT using high-density mapping catheters. Substrate mapping was performed in all patients. Procedural endpoints were VT non-inducibility and local abnormal ventricular activities (LAVAs) elimination. The primary end point was survival free from appropriate ICD shocks and secondary end points included VT storm and all-cause mortality. RESULTS: Sixty-four consecutive patients were included (68±9 years, 95% male, mean ejection fraction 33±11%, 39% VT storms, and 69% appropriate ICD shocks). LAVAs were identified in all patients and VT inducibility was found in 83%. LAVA elimination and non-inducibility were achieved in 93.8% and 60%, respectively. After a mean follow-up of 25±18 months, 90% and 85% of patients are free from appropriate ICD shocks at one and two years, respectively. The proportion of patients experiencing VT storm decreased from 39% to 1.6%. Overall survival was 89% and 84% at one and two years, respectively. CONCLUSIONS: RCA of VT in IHD using a high-density mapping substrate-based approach resulted in a steady freedom of ICD shocks and VT storm.

Ablación de taquicardia ventricular asistida con ECMO. Primera experiencia en nuestra institución / Ablation of ventricular tachycardia assisted with ECMO. First experience in our institution

Resumen La ablación con catéter de taquicardia ventricular ha demostrado mejorar la supervivencia y algunas veces es el único tratamiento efectivo, sobre todo en tormenta arrítmica; sin embargo la presencia de inestabilidad hemodinámica dificulta el procedimiento. El soporte con oxigenación por membrana extracorpórea (ECMO) es una alternativa para lograr el mapeo y ablación de taquicardia ventricular durante largos periodos de tiempo. Se presenta el caso de un paciente con cardiopatía isquémica y taquicardia ventricular con inestabilidad hemodinámica, en quien se realiza la ablación exitosa del sustrato mediante soporte con ECMO veno-arterial, sin episodios de taquicardia ventricular durante dos años de seguimiento.

Abstract Catheter ablation is useful for reducing drug refractory ventricular tachycardia (VT) episodes and can be life-saving when VT is incessant or arrhythmic storm. Left ventricular hemodynamic support may be required in patients with VT and hemodynamic instability. Extracorporeal membrane oxygenation (ECMO) support is an alternative to achieve ventricular tachycardia mapping and ablation over long periods of time. We present a case of successful catheter ablation of substrate in a patient with ischemic heart disease and ventricular tachycardia with hemodynamic instability performed using venous- arterial ECMO support. There were not episodes of ventricular tachycardia after 2 years of follow-up.

Una anomalía coronaria poco común como posible causa de taquicardia ventricular / A rare coronary anomaly as a possible cause of ventricular tachycardia

Resumen Se presenta el caso de un varón de 77 años que acude a urgencias tras un episodio sincopal en el contexto de una taquicardia ventricular monomorfa sostenida, por lo que se realizó cardioversión eléctrica. Para filiar la etiología del evento arrítmico ventricular se realizó un estudio de la anatomía coronaria mediante coronariografía invasiva, en el que se objetivaron las arterias coronarias sin lesiones significativas, pero como hallazgo casual se describió una anomalía coronaria, con ausencia de tronco coronario y salida independiente de las arterias circunfleja (Cx) y descendente anterior (DA) del seno coronario derecho, originándose la DA y la coronaria derecha del mismo ostium coronario. Dichos hallazgos se confirmaron mediante tomografía computarizada con reconstrucción tridimensional. Además, se objetivó un trayecto interarterial de la DA (entre las arterias aorta y pulmonar) y un trayecto intramuscular de la DA, así como un trayecto retroaórtico de la Cx. Debido a estos hallazgos, se procedió al implante de un desfibrilador automático implantable como prevención secundaria. El paciente tuvo una buena evolución posterior y fue dado de alta a su domicilio sin incidencias. Se presenta el caso para ayudar a comprender mejor estos trastornos, dado que actualmente constituyen un reto diagnóstico, ya que en muchas ocasiones se trata de un hallazgo casual en pruebas complementarias o incluso en autopsias. Además, es una causa relativamente frecuente de parada cardiorrespiratoria en pacientes jóvenes. De las muchas variables anatómicas que constituyen las anomalías coronarias, existe poca literatura sobre esta anomalía presentada y no hay imágenes similares a las de este caso.

Abstract We present the case of a 77-year-old man who came to the emergency room after a syncopal episode in the context of sustained monomorphic ventricular tachycardia for which electrical cardioversion was performed. In order to determine the etiology of the ventricular arrhythmic event, a study of the coronary anatomy was carried out using invasive coronary angiography, observing coronary arteries without significant lesions, although, as a chance finding, a coronary anomaly was described, with absence of the main coronary artery, with independent exit of circumflex (Cx) and anterior descending (AD) arteries of the right coronary sinus, originating the AD and right coronary artery from the same coronary ostium. These findings were later confirmed by computed tomography with 3D reconstruction. In addition, an interarterial path of AD (between aorta and pulmonary artery) and an intramuscular path of AD were observed, as well as a retro-aortic path of Cx. Given these findings, an implantable cardioverter defibrillator was implanted as secondary prevention. Good subsequent evolution with home discharge without incident. We present this case to help better understand these disorders, since they currently constitute a diagnostic challenge, since in many cases it is a chance finding in complementary tests or even in autopsies. It is also a relatively frequent cause of cardiorespiratory arrest in young patients. Of the many anatomical variables that make up the group of coronary anomalies, there is little bibliographic information on this anomaly presented, without finding images similar to those reported in this case.

Idiopathic left fascicular ventricular tachycardia in children and adolescents / Taquicardia ventricular fascicular izquierda idiopática en niños y adolescentes

Abstract Background: Idiopathic ventricular tachycardia (VT) in children with structurally normal hearts is generally unrelated to the risk of sudden arrhythmic death. Still, it may be associated with deterioration in the quality of life. VT involving the fascicular conduction system is the most typical form of idiopathic left VT. In this retrospective study, we describe the experience of the clinical presentation, catheter ablation, and long-term follow-up of left fascicular VT in children. Methods: An electrophysiological study was performed on consecutive children at a single tertiary center. Clinical fascicular left VT was induced by programmed stimulation, and catheter ablation was guided searching for Purkinje potentials. Results: We included 18 patients (0.8 patients/year): 14 (77.8%) males and four females. The mean age of the first VT episode was 8.5 ± 5 years. Intravenous verapamil administration was effective for paroxysmal fascicular VT but not for prevention of recurrences. The mean age at the time of catheter ablation was 11.1 ± 3.8 years (8 months-16 years). The mean weight was 36.8 ± 16.4 kg (8.7-58 kg). A 100% success rate was observed with catheter ablation after repeated procedures without major complications. Mean follow-up was 2.0 ± 1.2 years (1.0-4.0 years, median 1.5), with permanent success in all patients and no antiarrhythmic drug administration. Conclusions: Fascicular VT has an adverse clinical course in children. In most cases, this condition is drug refractory. Catheter ablation is successful and safe treatment and should represent the first-line approach in symptomatic children.

Resumen Introducción: La taquicardia ventricular (TV) idiopática en niños con corazón estructuralmente normal generalmente no se relaciona con el riesgo de muerte súbita arrítmica, pero puede asociarse con deterioro de la calidad de vida. La TV que involucra el sistema de conducción fascicular es la forma más común de TV izquierda idiopática. En este estudio retrospectivo se describe la experiencia de presentación clínica, ablación con catéter y seguimiento a largo plazo de TV fascicular en niños. Métodos: Se llevó a cabo un estudio electrofisiológico en niños consecutivos en un centro terciario. La TV fascicular clínica se indujo mediante la estimulación programada y la ablación con catéter fue guiada buscando el registro de potenciales de Purkinje. Resultados: Se incluyeron 18 pacientes (0.8 pacientes/año): 14 (77.8%) de sexo masculino y cuatro de sexo femenino. La media de edad a la cual ocurrió el primer episodio fue de 8.5 ± 5 años. La administración intravenosa de verapamilo fue eficaz para la TV fascicular paroxística, pero no para prevención de recurrencias. La media de edad de la ablación con catéter fue de 11.1 ± 3.8 años (8 meses-16 años). La media del peso fue 36.8 ± 16.4 kg (8.7-58 kg). Se observó el 100% de éxito con la ablación con catéter después de procedimientos repetidos sin complicaciones mayores. La media de seguimiento fue de 2.0 ± 1.2 años (1.0-4.0, mediana de 1.5 años) con éxito permanente en todos los pacientes y sin administración de fármacos antiarrítmicos. Conclusiones: En niños, el curso clínico de la TV fascicular es adverso. Además, en la mayoría de los casos, esta condición es refractaria a fármacos. La ablación con catéter resulta exitosa y segura y debe representar el abordaje de primera línea en niños sintomáticos.