Fibrilación auricular recurrente posterior a ablación de venas pulmonares: serie de casos / Recurrent atrial fibrillation after ablation of pulmonary veins: case series / Fibrilação atrial recorrentes pós ablação das veias pulmonares: série de casos

La ablación de las venas pulmonares se ha convertido en un tratamiento clave para fibrilación auricular (FA). Sin embargo, pueden ocurrir recurrencias. La estrategia disponible para la ablación después de una recurrencia de FA es controvertida, compleja y desafiante, y la información es limitada. Mediante la presentación de una serie de casos se resumen y discuten elementos clave en la comprensión y tratamiento del paciente con FA recurrente sintomática después de un procedimiento inicial de ablación de venas pulmonares que requiere un nuevo procedimiento de ablación. En las últimas décadas se ha obtenido una mejor comprensión de los mecanismos fisiopatológicos implicados en la FA recurrente posterior a ablación de venas pulmonares, lo que permite identificar factores asociados, crear scores predictores e implementar técnicas de optimización o estrategias adicionales para mejorar la durabilidad y la eficacia del aislamiento de venas pulmonares. Debido a que la reconexión de venas pulmonares es un hallazgo típico durante los procedimientos repetidos, ésta debe ser considerada el objetivo principal de una nueva ablación. Las estrategias de ablación adicional (desencadenantes extrapulmonares o sustratos arritmogénicos) son controvertidas y requieren investigaciones futuras.

Pulmonary vein ablation has become a key treatment for atrial fibrillation (AF). However, recurrences can occur. The ideal strategy for ablation after AF recurrence is controversial, complex, and challenging, with limited data available. By presenting a series of cases, we summarize and discuss key elements in the understanding and treatment of patients with symptomatic recurrent AF after an initial pulmonary vein ablation procedure who are subjected to a new ablation procedure. In recent decades, there has been a better understanding of the pathophysiological mechanisms involved in recurrent AF after pulmonary vein ablation, making it possible to identify associated factors, create predictive scores and implement optimization techniques or additional strategies to improve the durability and efficacy of pulmonary veins isolation. Because pulmonary vein reconnection is a typical finding during repeat procedures, it should be considered the primary goal for a repeat ablation procedure. Additional ablation strategies (extrapulmonary triggers or arrhythmogenic substrates) are controversial and require further investigation.

A ablação das veias pulmonares tornou-se um tratamento chave para fibrilação atrial (FA). No entanto, podem ocorrer recorrências. A estratégia ideal para a ablação após uma recorrência da FA é controversa, complexa e desafiadora e existem dados limitados. Através da apresentação de uma série de casos resumimos e discutimos elementos chave no entendimento e tratamento do paciente com FA recorrente sintomática após um procedimento inicial de ablação de veias pulmonares, que são submetidos a um novo procedimento de ablação. Nas últimas décadas obteve-se uma melhor compressão dos mecanismos fisiopatológicos envolvidos na FA recorrente pós-ablação de veias pulmonares, isso permite identificar fatores associados, criar scores preditores, implementar técnicas de otimização ou estratégias adicionais para melhorar a durabilidade e eficácia do isolamento de veias pulmonares. Dado que a reconexão de veias pulmonares é um achado típico durante os procedimentos repetidos deve ser considerado o objetivo principal para uma nova ablação. As estratégias de ablação adicional (desencadeadores extrapulmonares ou substratos arritmogénicos) são controversas e requerem investigação futura.

Relação entre Gordura Epicárdica e Fibrilação Atrial Não Pode Ser Totalmente Explicada pela Fibrose Atrial Esquerda / The Relationship between Epicardial Fat and Atrial Fibrillation Cannot Be Fully Explained by Left Atrial Fibrosis

Resumo Fundamento O tecido adiposo epicárdico (TAE) tem sido associado à fibrilação atrial (FA), mas seus mecanismos fisiopatológicos permanecem obscuros. Objetivos Medir a correlação entre TAE e fibrose do átrio esquerdo (AE), e avaliar sua capacidade de prever recidiva após o isolamento da veia pulmonar (IVP). Métodos Pacientes com FA inscritos para um primeiro procedimento de IVP foram submetidos à tomografia computadorizada (TC) cardíaca e ressonância magnética cardíaca (RMC) em menos de 48 horas. Quantificou-se o TAECE em imagens de TC realçadas com contraste no nível do tronco da coronária esquerda. Quantificou-se a fibrose do AE em RMC tridimensional com realce tardio isotrópico de 1,5 mm. Após o isolamento da veia pulmonar (IVP), os pacientes foram submetidos a seguimento para checar a recidiva da FA. A significância estatística foi definida com p<0,05. Resultados A maioria dos 68 pacientes (46 homens, idade 61±12 anos) tinha FA paroxística (71%, n=48). Os pacientes apresentavam volume TAECE mediano de 2,4 cm3/m2 (intervalo interquartil [IIQ] 1,6-3,2 cm3/m2) e um volume médio de fibrose do AE de 8,9 g (IIQ 5-15 g). A correlação entre TAECE e fibrose do AE foi estatisticamente significativa, mas fraca (coeficiente de correlação de postos de Spearman = 0,40, p=0,001). Durante um seguimento médio de 22 meses (IIQ 12-31), 31 pacientes (46%) tiveram recidiva da FA. A análise multivariada produziu dois preditores independentes de recidiva da FA: TAECE (FC 2,05, IC de 95% 1,51-2,79, p<0,001) e FA não paroxística (FC 2,36, IC de 95% 1,08-5,16, p=0,031). Conclusão A correlação fraca entre TAE e AE sugere que a fibrose do AE não é o principal mecanismo que liga o TAE e a FA. O TAE mostrou-se mais fortemente associado à recidiva da FA do que à fibrose do AE, corroborando a existência de outros mediadores mais importantes do TAE e da FA.

Abstract Background Epicardial adipose tissue (EAT) has been associated with atrial fibrillation (AF), but its pathophysiological mechanisms remain unclear. Objectives To measure the correlation between EAT and left atrium (LA) fibrosis, and to assess their ability to predict relapse after pulmonary vein isolation (PVI). Methods Patients with AF enrolled for a first PVI procedure underwent both cardiac computerized tomography (CT) and cardiac magnetic resonance (CMR) imaging within less than 48 hours. EATLMwas quantified on contrast-enhanced CT images at the level of the left main. LA fibrosis was quantified on isotropic 1.5 mm 3D delayed enhancement CMR. After pulmonary vein isolation (PVI), patients were followed up for AF relapse. Statistical significance was set at p<0.05. Results Most of the 68 patients (46 men, age 61±12 years) had paroxysmal AF (71%, n=48). Patients had a median EATLMvolume of 2.4 cm3/m2(interquartile range [IQR] 1.6-3.2 cm3/m2), and a median amount of LA fibrosis of 8.9 g (IQR 5-15 g). The correlation between EATLMand LA fibrosis was statistically significant but weak (Spearman's R=0.40, p=0.001). During a median follow-up of 22 months (IQR 12-31), 31 patients (46%) had AF relapse. Multivariate analysis yielded two independent predictors of AF relapse: EATLM(HR 2.05, 95% CI 1.51-2.79, p<0.001), and non-paroxysmal AF (HR 2.36, 95% CI 1.08-5.16, p=0.031). Conclusion The weak correlation between EAT and LA suggests that LA fibrosis is not the main mechanism linking EAT and AF. EAT was more strongly associated with AF relapse than LA fibrosis, supporting the existence of other more important mediators of EAT and AF.

Thawing rate predicts acute pulmonary vein isolation after second-generation cryoballoon ablation

OBJECTIVE: To evaluate whether thawing rate could be a novel predictor of acute pulmonary vein isolation (PVI) and explore the predictive value of thawing rate as a factor ensuring long-term PVI (vagus reflex). METHODS: A total of 151 patients who underwent cryoballoon ablation for atrial fibrillation (AF) were enrolled in this retrospective study between January 2017 and June 2018. The thawing rate was calculated using the thawing phase of the cryoablation curve. Receiver operating characteristic (ROC) curve was used to analyze the predictive value of the thawing rate for acute PVI and vagus reflex. RESULTS: ROC curve analyses revealed that the interval thawing rate at 15°C (ITR15) was the most valuable predictor of PVI, with the highest area under curve (AUC) value of the ROC curve. The best cut-off value of ITR15 for PVI was ≤2.14°C/S and its sensitivity and specificity were 88.62% and 67.18%, respectively. In addition, the ITR15 of the successful PVI group after cryoballoon ablation was significantly slower than the failed PVI group. ITR15 was a predictor of vagus reflex and the occurrence of vagus reflex group had a slower ITR15 compared to the non-occurrence group. CONCLUSIONS: Thawing rate was a novel predictor of acute PVI and the ITR15 was the most valuable predictor of acute PVI. In addition, ITR15 was a predictive factor ensuring long-term PVI (vagus reflex). Our study showed that thawing rate may serve in the early identification of useless cryoballoon ablation.

Relationship Between the Changes of Left Atrium, Pulmonary Vein Ostia and AF Recurrence After Radiofrequency Catheter Ablation by Enhanced Cardiac MRI Evaluation / 中国循环杂志

Objectives: To evaluate the changes of left atrial volume (LAV) and the maximum ostial cross-sectional area (CAS) of pulmonary vein (PV) in atrial fibrillation (AF) patients after circumferential pulmonary vein isolation radiofrequency catheter ablation (CPVA-RFCA) and to explore their relationship to AF recurrence by enhanced cardiac MRI evaluation. Methods: Our research included in 2 groups: Control group, n=20 healthy subjects and AF group, n=78 patients whom were classified into 2 subgroups as Paroxysmal AF subgroup, n=46 and Persistent AF subgroup, n=32; 66 patients received CPVA-RFCA and based on 6 months post-operative recurrence, they were divided into another set of 2 groups: AF recurrent subgroup, n=17 and Non-AF recurrent subgroup, n=49. Pre- and 6 months post-operative maximum ostial CSA of PV were measured by enhanced cardiac MRI, LAV were obtained by 3D reconstruction and the differences were compared between AF group and Control group, Paroxysmal AF subgroup and Persistent AF subgroup, AF recurrent subgroup and Non-AF recurrent subgroup; their relationships to AF recurrence were studied.Results: Compared with Control group, AF group had increased LAV and elevated ostial CSA of superior PV (SPV), both P<0.05. Compared with Paroxysmal AF subgroup, Persistent AF subgroup had increased LAV and elevated ostial CSA of SPV, both P<0.05. Compared with pre-operative condition, at 6 months after the operation, Non-AF recurrent subgroup showed reduced ostial CSAs in left SPV (LSPV), right SPV (RSPV), right inferior PV (RIPV) and decreased LAV, all P<0.05;while AF recurrent subgroup showed expanded RSPV and increased LAV,allP<0.05.Post-operative reductions of LAV and ostial CSA of SPV had close correlation; multivariate Logistic regression analysis indicated that LAV (HR=1.05, P<0.01)and ostial CSA of RSPV(HR=1.09,P=0.05)were related to AF recurrence after RFCA. Conclusions: CAPV-RFCA could reverse left atrial and PV remodeling in AF patients, LAV and ostial CSA of RSPV were related to post-operative AF recurrence.

Influence of circumferential pulmonary vein isolation on atrial effective refractory period in patients with paroxysmal atrial fibrillation / 中国介入心脏病学杂志

Objective To investigate the effects of circumferential pulmonary vein isolation (CPVI) on atrial effective refractory period (ERP) in patients with paroxysmal atrial fibrillation.Methods 30 patients who underwent radiofrequency catheter ablation for paroxysmal AF were enrolled in this study.Using FAM mode,the RA and LA anatomical models were achieved in the CARTO 3 system.SVC,MRA,RAA,LA-A,LA-R,LA-P,LAA,LSPV,LIPV,RSPV,RIPV,CSp,CSd,were respectively located in the RA or LA anatomical model.Before and after CPVI,ERPs were measured in different locations of the atrium using programmed stimulation.The ERPs of the RA (SVC,MRA,RAA,CSp),LA (LA-A,LA-R,LA-P,LAA,CSd),PVs (LSPV,RSPV,LIPV,RIPV) were compared.Bilateral CPVIs were completed in all patients,and PV-LA bidirectional conduction block was achieved.The changes of electrophysiological characteristics of atrium before and after CPVI were observed.Results (1) ERP at different locations in the atrium before CPVI:Comparisons of ERPs at different locations of atrium:RAA had the minimal ERPs[(197.4 ± 28.6) ms (P ＜ 0.01);followed by PVs measuring,respectively,LSPV (213.0 ± 47.5) ms,LIPV (208.9 ± 45.9) ms,RSPV (209.3 ± 43.6) ms,RIPV (213.5 ± 48.1) ms and LAA (218.1 ± 27.7) ms.Comparisons of ERPs in RA,LA,and PVs showed:PVs had the lowest ERPs (211.2 ± 35.2) ms versus RA ERP (227.0 ± 23.7) ms versus LA ERP (241.0 ± 21.5) ms (P ＜ 0.05).(2) Comparisons of ERPs before and after CPVI:Comparisons of ERPs at different locations of atrium showed:RAA [(197.4 ± 28.6) ms vs.(208.6 ± 32.2) ms,P=0.003],CSp [(234.7 ± 29.1) ms vs.(246.9 ± 29.7) ms,P=0.007],LA-R [(242.9 ± 28.9) ms vs.(258.3 ± 26.9) ms,P=0.003],LA-P [(252.2 ± 28.5) ms vs.(261.1 ± 30.2) ms,P=0.039]and CSd [(238.6 ± 28.3) ms vs.(250.3 ± 23.6) ms,P =0.009].ERPs were found statistically prolonged at all different locations after CPVI.Comparisons of ERPs at RAand LA after CPVI showed:RA [(227.0 ± 23.7) ms vs.(235.9 ± 21.7)ms,P=0.002]and LA [(241.0 ± 21.5) ms vs.(249.7 ± 19.9) ms,P =0.001],which were statistically increased after CPVI.(3) A total of 90 episodes of atrial arrhythmias were induced before CPVI which were found at RAA (n =17),LAA (n =12),and PVs (n =36).After CPVI,8 episodes of atrial arrhythmias were induced which were found at,RAA (n =4),LAA (n =3),and SVC (n =1).Conclusions (1) Compared with other parts of atrium,ERPs at PVs,LAA and RAA are significantly shorter in patients with paroxysmal AF.At PVs,LAA and RAA,atrial arrhythmias are easily to be induce by programmed stimulation.(2) In patients with paroxysmal Af:PVs has the shortest ERPsfollowed by RAs whereas LA ERPs is the longest.There is a large ERP gradient change between PVs and LA.(3) The ERPs at RAs,LAs,As,and LA-PV are prolonged after CPVI.(4) Atrial arrhythmia is less likely to be induced after CPVI.

Vena cava superior izquierda / Left superior vein cava

Mujer de 72 años con fibrilación auricular paroxística ingresó en la sala de electrofisiología para un aislamiento de venas pulmonares. La evaluación inicial con ecocardiografía intracardiaca reveló una dilatación significativa del seno coronario (fig. 1), la cual permitía el libre movimiento del catéter en su interior. De manera interesante, la ubicación del catéter decapolar en la parte lateral del seno generaba un aumento severo del automatismo atrial. Ante la sospecha de una vena cava superior izquierda persistente, se realizó reconstrucción tridimensional (EnSite NavX, St Jude Medical®) logrando visualizar el trayecto de la vena cava superior izquierda en su totalidad y su relación con el seno coronario (fig. 2). Durante el desarrollo embriológico normal, la vena cava superior izquierda involuciona y su trayecto intrapericárdico se convierte en la vena (ligamento) de Marshall. Aunque se ha documentado en aproximadamente el 0,2% de los pacientes llevados a estudio electrofisiológico (convirtiéndola en la alteración de las venas torácicas más común), pasa inadvertida debido a la ausencia de manifestaciones hemodinámicas1. De hecho, la mayoría se diagnostica de manera casual durante exámenes ordenados por otras razones.

Perioperative atrial fibrillation: A systematic review of evolving therapeutic options in pharmacologic and procedural management.

Given the high incidence of atrial fibrillation (AF) in the surgical population and the associated morbidity, physicians managing these complicated patients in the perioperative period need to be aware of the new and emerging trends in its therapy. The cornerstones of AF management have always been rate/rhythm control as well as anticoagulation. Restoration of sinus rhythm remains the fundamental philosophy as it maintains the atrial contribution to cardiac output and improves ventricular function. The recent years have seen a dramatic increase in the number of randomized AF trials that have made significant advances to our understanding of both pharmacologic and procedural management, from the introduction of the new generation of oral anticoagulants (NOAC’s) to catheter approaches for AF ablation. This paper will summarize the newest data that will affect the perioperative management of these patients.

Current status and dilemma of radiofrequency ablation for atrial fibrillation / 解放军医学杂志

The mechanism of triggering and maintaining atrial fibrillation (AF) is still not clear. There are different understandings about triggering and maintenance of AF, and therapeutic strategies relevant to them could not reach an agreement. In recent years, basic researches on AF have made greater progress. For example, the atrial rotor and autonomic nerve plexus theories has also been identified clinically, and it changed the strategies of radiofrequency ablation treatment for AF. This article summarizes the mechanism and current status of AF ablation.

Changes in P-wave polarity and amplitude after circumferential pulmonary vein isolation / 第二军医大学学报

Objective: To observe the influence of circumferential pulmonary vein isolation (CPVI) on P-wave polarity and amplitude and to investigate whether the changes of P-wave are associated with patient outcomes after initial CPVI. Methods Fifty patients with paroxysmal atrial fibrillation (AF) underwent CPVI. For each patient, electrocardiograph (ECG) recordings were taken before and 7 days after ablation. The P-wave polarities and amplitudes were analyzed. Successful CPVI was defined as freedom of symptomatic and asymptomatic AF at the end of two consecutive follow-ups. Results: The amplitude of positive P-wave was significantly decreased in the leads of I, II, III, aVF, V5, and V6 after ablation (P<0.05). The amplitude of negative P-wave was significantly decreased in the leads of aVR and aVF after ablation (P<0.05). The total amplitude of P-wave was significantly decreased in the leads of I, II, aVR, V5 and V6 after ablation (P<0.05). The negative P-wave in the lead of III and the positive P-wave in the lead of aVL were increased after ablation. The amplitudes of negative, positive and total P-waves before and after ablation were not significantly different between successful CPVI (n=39) and failure CPVI (n=11) groups. Conclusion: CPVI can result in noticeable reduction of P-wave amplitude in several leads of ECG, indicating the reduction of left atrial electric capacity. The changes of P-wave polarity indicate a P-wave vector shift. The reduction degree of P-wave amplitude has no predictive value for the success or failure of CPVI.

Estrategias de aislamiento de las venas pulmonares durante la ablación de fibrilación auricular / Pulmonary vein isolation strategies during ablation of atrial fibrillation

Introducción: La ablación de la fibrilación auricular (FA) es un tratamiento potencialmente curativo para esta arritmia, siendo su principal objetivo el aislamiento o desconexión eléctrica de las venas pulmonares (VP). El aislamiento de las 4 VP ha demostrado mayor beneficio que solo el aislamiento de la VP culpable del inicio de la FA (ablación focal). Para aislar las VP se realizan líneas de ablación alrededor de ellas, éstas se pueden efectuar en la unión veno-auricular (circunferencial antral) o en su ostium (ostial). El objetivo de este estudio es describir estas estrategias de aislamiento de las VP en un grupo de pacientes sometidos a ablación de FA. Métodos: Los criterios de selección fueron pacientes con FA paroxística sintomática recurrente a pesar de tratamiento antiarrítmico y FA persistente sintomática sin cardiopatía estructural significativa, además, con un seguimiento mínimo de 3 meses post ablación. Se analizaron las estrategias de ablación focal versus aislamiento de las 4 VP y se evaluaron las líneas de ablación antral y ostial. El éxito fue definido como ausencia de FA, según síntomas y holter de arritmias de 24 horas, sin necesidad de tratamiento antiarrítmico. Resultados: Se analizaron 50 procedimientos en 42 pacientes, por recurrencia de FA se reintervinieron 6 pacientes por una vez y un paciente 2 veces. Durante un seguimiento de 19 +/- 15 meses se alcanzo el éxito en 30 pacientes (71.4 por ciento). En 19 pacientes la estrategia inicial de ablación fue focal y en 23 pacientes fue en las 4 VP, alcanzándose el éxito en 12 pacientes (63.1 por ciento) y en 20 pacientes (87 por ciento) respectivamente (p=0.14). Se realizo ablación antral en las VP izquierdas en 22 casos y en las VP derechas en 14 casos, logrando la desconexión eléctrica en 3 casos (13.6 por ciento) y ningún caso respectivamente. En los restantes casos se complemento con ablación ostial para alcanzar su aislamiento, en 4 VP este objetivo no se alcanzo. Un paciente ...

Introduction: Ablation of pulmonary veins is a potentially curative procedure for atrial fibrillation (AF). The objective is to electrically isolate the pulmonary veins from the left atrium. Ablation of all pulmonary veins (PVs) has been more effective than the isolation of the PV responsible for the initiation of AF (focal ablation). Ablation lines to isolate PVs can be performed around the PV-LA junction (circumferential) or at the PV os-tium. Aim: to describe circumferential and ostium ablation strategies in a group of patients with AF Methods: Patients with recurrent paroxistic AF unresponsive to anti arrhythmic therapy or patients with persistent symptomatic lone AF were included. Focal vs 4 PV ablation as well as circumferential vs ostial techniques were compared. Success was defined as being free from AF, as judged by symptoms and Holter recordings. Results: 50 procedures were performed in 42 patients. 6 patients had a repeat ablation procedure and one had 2 additional ablation procedures, due to recurrence of AF. 30 patients (71.4 percent) were AF free after 19 +/- 15 months of follow-up. 12 of 19 patients (63.1 percent) with focal ablation were AF free as compared to 20 of 23 submitted to 4PV ablation (87 percent) (pNS) . Three of 22 patients (13.6 percent) had successful AF ablation while none of right PVs ablation succeeded. Ostial ablation was performed after failure of circumferential ablation in unsuccessful cases. One patient developed stenosis in a left PV, which was successfully treated with stent-less angioplasty. Conclusion: Ablation is an effective therapy to prevent recurrence of AF. Focal ablation is generally needed to achieve effective electrical isolation of PVs.

Outcomes of radiofrequency ablation in atrial tachyarrhythmia patients following circumferential pulmonary vein isolation / 第二军医大学学报

Objective: To observe the outcomes of radiofrequency ablation in patients with atrial tachyarrhythmia (ATa) after circumferential pulmonary vein isolation (CPVI), so as to discuss the related mechanism. Methods: A total of 64 patients underwent mapping and ablation using an electroanatomic mapping system (CARTO) at a mean of (3.7±2.4) months after the first CPVA procedure. Results: A total of 78 types of ATa were mapped, including 30 (38.5%) with re-entry mechanism and 48 (61.5%) with focal mechanism. Among reentrant ATa 12 had common atrial flutter and 18 had left atrial re-entry; the reentrant circuits were related to the mitral isthmus, the anterior wall of the left atrium, and the gaps on previous encircling lines. The tachycardias were unstable in 2 patients and were not mapped. Catheter ablation was successful in 56 of the 64 patients (87.5%), and cardioversion was needed in 8 patients to achieve sinus rhythm. During a mean follow-up of 13-21(16.5±2.9) months, 60 (93.8%) cases no longer had ATa. Conclusion: ATa after CPVA can have macro-reentrant and focal mechanisms. These arrhythmias can be successfully mapped and ablated with an electroanatomic mapping system.

A multidisciplinary approach to atrial fibrillation.

We report a case with mitral regurgitation and atrial fibrillation and discuss the management of atrial fibrillation. The successful result of combining of mitral valve repair and simple pulmonary vein isolation in a single procedure is presented.