Comparison between cryotherapy and radiofrequency energy sources for parahisian accessory pathway percutaneous ablation.

BACKGROUND: Catheter ablation of parahisian accessory pathways (PHAP) are challenging due to their proximity to the normal conduction system. Retrospective studies suggest that cryoablation has a better safety profile but a higher recurrence rate when compared to radiofrequency ablation (RFCA). The objective of this study was to compare the results of parahisian AP ablation performed by electrophysiologists with experience in both technologies. METHODS: Prospective single-center, non-blinded and 1:1 model was used. Patients included had parahisian AP confirmed by an electrophysiological study and referred for radiofrequency or cryotherapy ablation according to current guidelines, under fluoroscopic guidance. No electroanatomic mapping was used. RESULTS: A total of 30 patients (mean age of 25±9.4 years; 90% male) were enrolled between Oct/2018 to Feb/2020. Acute success rate between RFCA and CRYO were similar (93% vs. 87%, p = 0.54). A nonsignificant reduction in short-term recurrence rate for RFCA (14% vs. 30%, p = 0.3) and mechanical trauma (6% vs. 20%; p = 0.28) was observed. Long-term recurrence rate and event-free survival time were similar in both groups after 1-year follow-up (p = 0.286). No persistent complete AV block or conduction disturbance was also observed. CONCLUSION: Considering the limitation of a small sample size and the lack of use of electroanatomic mapping for RFCA, the efficacy and safety profile of parahisian AP ablation with RFCA was not different from CRYO, when performed by experienced electrophysiologists. No cases of permanent complete AV block were reported with either energy modalities.

Peculiar Aspects of Patients with Inherited Arrhythmias during the COVID-19 Pandemic. / Peculiaridade dos Pacientes com Arritmias Hereditárias na Pandemia pela COVID-19.

Since December 2019 we have observed the rapid advance of the severe acute respiratory syndrome caused by the new coronavirus (SARS-CoV-2). The impact of the clinical course of a respiratory infection is little known in patients with hereditary arrhythmias, due to the low prevalence of these diseases. Patients who present with infectious conditions may exacerbate hidden or well-controlled primary arrhythmias, due to several factors, such as fever, electrolyte disturbances, drug interactions, adrenergic stress and, eventually, the septic patient's own myocardial damage. The aim of this review is to highlight the main challenges we may encounter during the Covid 19 pandemic, specifically in patients with hereditary arrhythmias, with emphasis on the congenital long QT syndrome (LQTS), Brugada syndrome (SBr), ventricular tachycardia polymorphic catecholaminergic (CPVT) and arrhythmogenic right ventricular cardiomyopathy.

Desde dezembro de 2019, observamos o rápido avanço da síndrome respiratória aguda grave causada pelo coronavírus 2019 (SARS-CoV-2). O impacto da evolução clínica de uma infecção respiratória é pouco conhecido em pacientes portadores de arritmias hereditárias, devido à baixa prevalência dessas doenças. Os pacientes que apresentam quadros infecciosos podem exacerbar arritmias primárias ocultas ou bem controladas, por diversos fatores, tais como febre, distúrbios eletrolíticos, interações medicamentosas, estresse adrenérgico e, eventualmente, o próprio dano miocárdico do paciente séptico. O objetivo desta revisão é destacar os principais desafios que podemos encontrar durante a pandemia pela Covid 19, especificamente nos pacientes com arritmias hereditárias, com destaque para a síndrome do QT longo congênito (SQTL), a síndrome de Brugada (SBr), a taquicardia ventricular polimórfica catecolaminérgica (TVPC) e a cardiomiopatia arritmogênica do ventrículo direito.

Peculiaridade dos pacientes com arritmias hereditárias na pandemia pela COVID-19 / Peculiar aspects of patients with Inherited arrhythmias during the COVID-19 pandemic

Resumo Desde dezembro de 2019, observamos o rápido avanço da síndrome respiratória aguda grave causada pelo coronavírus 2019 (SARS-CoV-2). O impacto da evolução clínica de uma infecção respiratória é pouco conhecido em pacientes portadores de arritmias hereditárias, devido à baixa prevalência dessas doenças. Os pacientes que apresentam quadros infecciosos podem exacerbar arritmias primárias ocultas ou bem controladas, por diversos fatores, tais como febre, distúrbios eletrolíticos, interações medicamentosas, estresse adrenérgico e, eventualmente, o próprio dano miocárdico do paciente séptico. O objetivo desta revisão é destacar os principais desafios que podemos encontrar durante a pandemia pela Covid 19, especificamente nos pacientes com arritmias hereditárias, com destaque para a síndrome do QT longo congênito (SQTL), a síndrome de Brugada (SBr), a taquicardia ventricular polimórfica catecolaminérgica (TVPC) e a cardiomiopatia arritmogênica do ventrículo direito.

Abstract Since December 2019 we have observed the rapid advance of the severe acute respiratory syndrome caused by the new coronavirus (SARS-CoV-2). The impact of the clinical course of a respiratory infection is little known in patients with hereditary arrhythmias, due to the low prevalence of these diseases. Patients who present with infectious conditions may exacerbate hidden or well-controlled primary arrhythmias, due to several factors, such as fever, electrolyte disturbances, drug interactions, adrenergic stress and, eventually, the septic patient's own myocardial damage. The aim of this review is to highlight the main challenges we may encounter during the Covid 19 pandemic, specifically in patients with hereditary arrhythmias, with emphasis on the congenital long QT syndrome (LQTS), Brugada syndrome (SBr), ventricular tachycardia polymorphic catecholaminergic (CPVT) and arrhythmogenic right ventricular cardiomyopathy.

Catheter Ablation of Focal Atrial Tachycardia with Early Activation Close to the His-Bundle from the Non Coronary Aortic Cusp. / Ablação por Cateter de Taquicardia Atrial Focal com Ativação Precoce Próxima ao Feixe de His, a Partir da Cúspide Aórtica não Coronária.

BACKGROUND: Atrial tachycardia (AT) ablation with earliest activation site close to the His-Bundle is a challenge due to the risk of complete AV block by its proximity to His-Purkinje system (HPS). An alternative to minimize this risk is to position the catheter on the non-coronary cusp (NCC), which is anatomically contiguous to the para-Hisian region. OBJECTIVES: The aim of this study was to perform a literature review and evaluate the electrophysiological characteristics, safety, and success rate of catheter-based radiofrequency (RF) delivery in the NCC for the treatment of para-Hisian AT in a case series. METHODS: This study performed a retrospective evaluation of ten patients (Age: 36±10 y-o) who had been referred for SVT ablation and presented a diagnosis of para-Hisian focal AT confirmed by classical electrophysiological maneuvers. For statistical analysis, a p-value of <0.05 was considered statistically significant. RESULTS: The earliest atrial activation at the His position was 28±12ms from the P wave and at the NCC was 3±2ms earlier than His position, without evidence of His potential in all patients. RF was applied on the NCC (4-mm-tip catheter; 30W, 55ºC), and the tachycardia was interrupted in 5±3s with no increase in the PR interval or evidence of junctional rhythm. Electrophysiological tests did not reinduce tachycardia in 9/10 of patients. There were no complications in all procedures. During the 30 ± 12 months follow-up, no patient presented tachycardia recurrence. CONCLUSION: The percutaneous treatment of para-Hisian AT through the NCC is an effective and safe strategy, which represents an interesting option for the treatment of this complex arrhythmia. (Arq Bras Cardiol. 2021; 116(1):119-126).

FUNDAMENTO: A ablação da taquicardia atrial (TA) com local de ativação mais precoce próxima ao feixe de His é um desafio, devido ao risco de bloqueio de AV completo por sua proximidade ao sistema de His-Purkinje (SHP). Uma alternativa para minimizar esse risco é posicionar o cateter na cúspide não coronária (CNC), que é anatomicamente contígua à região para-Hissiana. OBJETIVOS: O objetivo deste estudo foi fazer uma revisão de literatura e avaliar as características eletrofisiológicas, a segurança e o índice de sucesso de aplicação de radiofrequência (RF) por cateter na CNC para o tratamento de TA para-Hissiana em uma série de casos. MÉTODOS: Avaliamos retrospectivamente dez pacientes (Idade: 36±10 anos) que foram encaminhados para ablação de taquicardia paroxística supraventricular (TPSV) e haviam sido diagnosticados com TA focal para-Hissiana confirmada por manobras eletrofisiológicas clássicas. Para a análise estatística, um P valor d <0.05 foi considerado estatisticamente significativo. RESULTADOS: A ativação atrial mais precoce na posição His foi de 28±12ms da onda P, e a CNC foi 3±2ms antes da posição His, sem evidência de potencial His em todos os pacientes. Foi aplicada RF à CNC (cateter de ponta de 4-mm; 30W, 55°C) e a taquicardia foi interrompida em 5±3s sem aumento no intervalo PR ou evidência de um ritmo juncional. Os testes eletrofisiológicos não induziram novamente a taquicardia em 9/10 pacientes. Não houve complicações em nenhum procedimento. Durante o período de acompanhamento de 30 ± 12 meses, nenhum paciente apresentou recorrência de taquicardia. CONCLUSÃO: O tratamento percutâneo de TA para-Hissiana por meio de CNC é uma estratégia segura e eficiente, tornando-se uma opção interessante para o tratamento de arritmia complexa. (Arq Bras Cardiol. 2021; 116(1):119-126).

Advanced management of ventricular arrhythmias in chronic Chagas cardiomyopathy.

Chagas cardiomyopathy is a parasitic infection caused by Trypanosoma cruzi. Structural and functional abnormalities are the result of direct myocardial damage by the parasite, immunological reactions, dysautonomia, and microvascular alterations. Chronic Chagas cardiomyopathy (CCC) is the most serious and important manifestation of the disease, affecting up to 30% of patients in the chronic phase. It results in heart failure, arrhythmias, thromboembolism, and sudden cardiac death. As in other cardiomyopathies, scar-related reentry frequently results in ventricular tachycardia (VT). The scars typically are located in the inferior and lateral aspects of the left ventricle close to the mitral annulus extending from endocardium to epicardium. The scars may be more prominent in the epicardium than in the endocardium, so epicardial mapping and ablation frequently are required. Identification of late potentials during sinus rhythm and mid-diastolic potentials during hemodynamically tolerated VT are the main targets for ablation. High-density mapping during sinus rhythm can identify late isochronal regions that are then targeted for ablation. Preablation cardiac magnetic resonance imaging with late enhancement can identify potentials areas of arrhythmogenesis. Therapeutic alternatives for VT management include antiarrhythmic drugs and modulation of the cardiac autonomic nervous system.