National Registry on Cardiac Electrophysiology (2012)

Based on a survey sent to Portuguese centers that perform diagnostic and interventional electrophysiology and/or implantable cardioverter-defibrillator (ICD) implantations, the authors analyze the number and type of procedures performed during 2012 and compare these data with previous years. In 2012, a total of 2561 diagnostic electrophysiologic studies were performed, which were followed by ablation in 2017 cases, representing a steady situation compared with the previous year. There was a 12% increase in the number of ablation procedures for atrial fibrillation, making it for the first time the most frequent indication for ablation, overtaking atrioventricular nodal reentrant tachycardia. The total number of first ICD implantations was 1048 (around 100 per million population), of which 375 were cardiac resynchronization devices (BiV ICDs). This represents a slight decrease (3.3%) in the total number of new implants, with an increase of 10% in the number of BiV ICDs compared to the previous year. However, there was a considerable increase in the number of ICD generator replacements, resulting in an overall increase of 3.5% in implantations performed in 2012. Some comments are made regarding developments in this activity and its current status, and on some factors that may influence the dynamics of this area of interventional cardiology.

How To Follow Atrial Fibrillation Ablation Patients?

Catheter ablation is an established treatment option for symptomatic atrial fibrillation (AF), with circumferential pulmonary vein isolation being considered the cornerstone of the procedure. However, this is a complex intervention with potential major complications and with common arrhythmia recurrences. There is consensus among experts that all patients should be seen in follow-up regularly after AF ablation. To date there are limited data regarding the best methodology for routine clinical follow-up of this population. This review summarizes a contemporary insight into management of late complications following AF ablation, post-procedural anticoagulation and arrhythmia monitoring strategies, in order to prevent thromboembolic events, detect and treat arrhythmia recurrences, and discuss the use of upstream therapies after AF ablation.

The Proarrhythmic Effect of Cardiac Resynchronization Therapy: an Issue that Should Be Borne in Mind

The demonstrated benefits of cardiac resynchronization therapy (CRT) in reducing mortality and hospitalizations for heart failure, improving NYHA functional class and inducing reverse remodeling have led to its increasing use in clinical practice. However, its potential contribution to complex ventricular arrhythmias is controversial.We present the case of a female patient with valvular heart failure and severe systolic dysfunction, in NYHA class III and under optimal medical therapy, without previous documented ventricular arrhythmias. After implantation of a CRT defibrillator, she suffered an arrhythmic storm with multiple episodes of monomorphic ventricular tachycardia (VT), requiring 12 shocks. Subsequently, a pattern of ventricular bigeminy was observed, as well as reproducible VT runs induced by biventricular pacing. Since no other vein of the coronary sinus system was accessible, it was decided to implant an epicardial lead to stimulate the left ventricle, positioned in the left ventricular mid-lateral wall. No arrhythmias were detected in the following six months. This case highlights the possible proarrhythmic effect of biventricular pacing with a left ventricular lead positioned in the coronary sinus venous system.

Cost-Effectiveness of Non-Vitamin K Antagonist Oral Anticoagulants for Atrial Fibrillation in Portugal

INTRODUCTION AND OBJECTIVES:Recently, three novel non-vitamin K antagonist oral anticoagulants received approval for reimbursement in Portugal for patients with non-valvular atrial fibrillation (AF). It is therefore important to evaluate the relative cost-effectiveness of these new oral anticoagulants in Portuguese AF patients. METHODS: A Markov model was used to analyze disease progression over a lifetime horizon. Relative efficacy data for stroke (ischemic and hemorrhagic), bleeding (intracranial, other major bleeding and clinically relevant non-major bleeding), myocardial infarction and treatment discontinuation were obtained by pairwise indirect comparisons between apixaban, dabigatran and rivaroxaban using warfarin as a common comparator. Data on resource use were obtained from the database of diagnosis-related groups and an expert panel. Model outputs included life years gained, quality-adjusted life years (QALYs), direct healthcare costs and incremental cost-effectiveness ratios (ICERs). RESULTS:Apixaban provided the most life years gained and QALYs. The ICERs of apixaban compared to warfarin and dabigatran were €5529/QALY and €9163/QALY, respectively. Apixaban was dominant over rivaroxaban (greater health gains and lower costs). The results were robust over a wide range of inputs in sensitivity analyses. Apixaban had a 70% probability of being cost-effective (at a threshold of €20 000/QALY) compared to all the other therapeutic options. CONCLUSIONS:Apixaban is a cost-effective alternative to warfarin and dabigatran and is dominant over rivaroxaban in AF patients from the perspective of the Portuguese national healthcare system. These conclusions are based on indirect comparisons, but despite this limitation, the information is useful for healthcare decision-makers.

Time to Left Ventricular Reverse Remodeling after Cardiac Resynchronization Therapy: Better Late than Never

INTRODUCTION: Left ventricular reverse remodeling (LVRR), defined as reduction of end-diastolic and end-systolic dimensions and improvement of ejection fraction, is associated with the prognostic implications of cardiac resynchronization therapy (CRT). The time course of LVRR remains poorly characterized. Nevertheless, it has been suggested that it occurs ≤6 months after CRT. OBJECTIVE: To characterize the long-term echocardiographic and clinical evolution of patients with LVRR occurring >6 months after CRT and to identify predictors of a delayed LVRR response. METHODS: A total of 127 consecutive patients after successful CRT implantation were divided into three groups according to LVRR response: Group A, 19 patients (15%) with LVRR after >6 months (late LVRR); Group B, 58 patients (46%) with LVRR before 6 months (early LVRR); and Group C, 50 patients (39%) without LVRR during follow-up (no LVRR). RESULTS: The late LVRR group was older, more often had ischemic etiology and fewer patients were in NYHA class ≤II. Overall, group A presented LVRR between group B and C. This was also the case with the percentage of clinical response (68.4% vs. 94.8% vs. 38.3%, respectively, p<0.001), and hospital readmissions due to decompensated heart failure (31.6% vs. 12.1% vs. 57.1%, respectively, p<0.001). Ischemic etiology (OR 0.044; p=0.013) and NYHA functional class

Atrial flutter complicating severe leptospirosis: a case report

Cardiac disturbances are relatively common and electrocardiographic abnormalities may be found in more than 70% of patients with leptospirosis. We report the case of a 68 year-old male with severe leptospirosis who developed atrial flutter. Effective treatment was done with amiodarone. The patient became clinical stable, with complete recovery. Rigorous clinical observation and continuous electrocardiogram (ECG) monitoring may facilitate the identification of rhythm disorders, and thus prevent a probable fatal outcome, in severe cases of leptospirosis.

Emprego de altas doses de amiodarona via oral na reversão da fibrilação atrial no pós-operatório de cirurgia cardíaca

OBJETIVO: Relatar a experiência no emprego de altas doses de amiodarona via oral (1800mg/d) na reversão da fibrilação atrial (FA) em pacientes submetidos à cirurgia cardíaca. MÉTODOS: Analisados, retrospectivamente, 80 pacientes que apresentaram FA no pós operatório de cirurgia cardíaca, constituindo 2 grupos: grupo A com 28 pacientes em uso de amiodarona e grupo B recebendo digital, sendo que este grupo foi subdividido no grupo C com 21 pacientes onde foi associada amiodarona, quando não houvesse reversão da arritmia em 48h. As diferenças foram consideradas significativas para um valor de P<0,05. RESULTADOS: A FA esteve presente em 19,4% dos pacientes operados, com predomínio no sexo masculino e entre 60-69 anos. No grupo A, a reversão ocorreu em 78,6% dos casos, grupo B, o digital obteve sucesso em 60% das vezes e no grupo C, a taxa de sucesso foi de 90%. CONCLUSÃO: O uso de altas doses de amiodarona via oral, isolada ou em combinação com digital pode ser segura e eficaz no tratamento da FA em pós operatório de cirurgia cardíaca.

Análise da recorrência de fibrilação atrial durante terapia com sotalol ou quinidina

OBJETIVO: Analisar a incidência e as características das crises de recorrência de fibrilação atrial (FA) em pacientes sob terapia com sotalol ou quinidina. MÉTODOS: Cento e vinte e um pacientes receberam de forma randômica sotalol (58 pacientes) ou quinidina (63 pacientes) após reversão de FA paroxística e foram acompanhados, ambulatorialmente, por 6 meses. As sintomatologias e as freqüências ventriculares ao eletrocardiograma de 12 derivações da crise inicial e da recorrência foram comparadas entre os grupos de drogas. As características clínicas e os dados do ecocardiograma foram analisados como preditores de recorrência. RESULTADOS: Dezessete (14%) pacientes apresentaram recorrência da arritmia, 7 (12%) em uso de sotalol e 10 (16%) em uso de quinidina. A recorrência ocorreu mais tardiamente no grupo tratado com sotalol (mediana de 69 dias) em comparação ao grupo tratado com quinidina (mediana de 10 dias) (p=0,04). A sintomatologia esteve presente em 14 (82%) pacientes na crise inicial e em 8 (47%) pacientes na recorrência. O tratamento antiarrítmico proporcionou recorrências menos sintomáticas (p<0,04), não sendo possível demonstrar diferença significante entre as terapias. Somente os pacientes tratados com sotalol apresentaram menor freqüência ventricular na recorrência em comparação à crise inicial (p<0,02). Todas as variáveis falharam em predizer recorrência da FA. CONCLUSÃO: Não foi possível demonstrar diferença entre o sotalol e a quinidina na prevenção de FA. O tratamento antiarrítmico proporcionou a ocorrência de recorrências menos sintomáticas. Os pacientes tratados com sotalol apresentaram recorrência mais tardiamente e freqüência ventricular significantemente menor na recorrência em comparação à crise inicial.

Ablação por cateter do flutter atrial. Caracterização eletrofisiológica da interrupção da condução pelos istmos posterior e septal

OBJETIVO: Avaliar os tipos de bloqueio obtidos nos istmos posterior (entre o anel tricuspídeo e veia cava inferior) e septal (entre o anel tricuspídeo e óstio do seio coronário), após ablação do flutter atrial (FLA). MÉTODOS: Foram submetidos à ablação por radiofreqüência (RF) 14 pacientes com FLA tipo I (9 homens) em 16 procedimentos. A ativação atrial ao redor do anel tricuspídeo foi avaliada em ritmo sinusal utilizando-se cateter "Halo" com 10 pares de eletrodos (H1-2 a H19-20), durante estimulação do seio coronário proximal (SCP) e região póstero-lateral do átrio direito (H1-2), antes e após ablações lineares. De acordo com a frente de programação do impulso definiu-se: ausência de bloqueio (condução bidirecional), bloqueio incompleto (condução bidirecional com retardo num dos sentidos) e bloqueio completo (ausência de condução pelo istmo). O intervalo desta ativação (deltaSCP/H1-2) foi analisado. RESULTADOS: Bloqueio completo foi obtido em 7 procedimentos (44%) e incompleto em 4 (25%). O deltaSCP/H1-2 foi de 74 ± 26ms no primeiro grupo e de 30,5 ± 7,5ms no segundo (p<0,05). Em 5 casos não demonstrou-se bloqueio. Num seguimento médio de 12 meses, ocorreu recorrência do FLA nos 6 pacientes com bloqueio incompleto ou ausente e em nenhum com bloqueio completo (p<0,001). CONCLUSÃO: A verificação de bloqueio completo pelo mapeamento multipolar atrial é uma estratégia eficaz para definir o sucesso e recorrência clínica na ablação do FLA tipo I.

Mixoma atrial esquerdo com acidente vascular cerebral isquêmico em criança

É apresentado um caso de mixoma atrial esquerdo associado a acidente vascular cerebral embólico em paciente do sexo feminino, com oito anos de idade. Feita a exérese do tumor, a criança apresentava, dois meses após cirurgia, presença de massa septoatrial esquerda, sugerindo recidiva, mantendo-se, porém, assintomática. A revisão da literatura enfatiza a raridade e a agressividade com que este tumor acomete esta faixa etária, além de salientar baixas taxas de recidiva após sua retirada.

Ablação com radiofreqüência do flutter atrial tipo I. Importância do bloqueio bidirecional do istmo entre a veia cava inferior e o anel da valva tricúspide

OBJETIVO: Estudar a importância clínica da determinação eletrofisiológica da presença de bloqueio bidirecional na condução pelo istmo localizado entre a veia cava inferior e o anel da valva tricúspide (VCI - AT), após a ablação do flutter atrial tipo I (FL) com radiofreqüência (RF). MÉTODOS: Quarenta pacientes consecutivos (idade média 51±11 anos) com FL foram submetidos a ablação do istmo VCI-AT com RF. Em 30 pacientes (GI), o sucesso foi avaliado pela interrupção e não reindução do FL com estimulação atrial programada. Nos últimos 10 pacientes foi avaliada também a condução bidirecional pelo istmo, com cateteres posicionados na sua entrada e saída e em cada lado da linha de bloqueio. O bloqueio foi considerado bidirecional quando ocorrido nos dois sentidos e unidirecional quando ocorrido em um só sentido. RESULTADOS: Vinte e seis (86%) pacientes do GI e 10 (100%) do GII tiveram sucesso imediato (p= 0,5558). Durante o seguimento, 7 (30%) de 23 pacientes do GI e 3 (30%) de 9 do GII tiveram recorrência de FL (p= NS). Os três pacientes do GII que apresentaram recorrência tinham bloqueio unidirecional, enquanto os seis casos sem recorrência tinham bloqueio bidirecional (p=0,012). CONCLUSÃO: A demonstração de bloqueio bidirecional no istmo VCI-AT, obtida imediatamente após a ablação do FL com RF, relaciona-se a menor índice de recorrência clínica, devendo ser o critério preferencial para término do procedimento.

Percutaneous closure of atrial septal defects. The role of transesophageal echocardiography

PURPOSE: Evaluation of the role of transesophageal echocardiography in percutaneous closure of atrial septal defects (ASD) with the Amplatzer septal occluder. METHODS: Patients were selected for percutaneous closure of ASD by transesophageal echocardiography (TEE), which was also used to monitor the procedure, helping to select the appropriate size of the Amplatzer device, to verify its position, and to access the immediate results of the procedure. During the follow-up, TEE was used to evaluate the presence and magnitude of residual shunt (RS), device position, and right cardiac chamber diameters. RESULTS: Twenty-two (40%) of a total of 55 studied patients were selected. Thirteen underwent Amplatzer device implantation, eight are still waiting for it, and one preferred the conventional surgical treatment. All procedures were successful, which was mainly due to proper patient selection. Six (23%) patients acutely developed RS, which spontaneously disapeared at the three-month follow-up examination in three patients. There was a significant reduction in the right ventricle diastolic diameter, from 27mm (average) to 24mm and 20mm, one and three months after the procedure, respectively (p<0.0076). CONCLUSION: With the aid of TEE, percutaneous closure of ASD can be successfully, safely, and effectively performed.

Atrial infarction is a unique and often unrecognized clinical entity

A patient with heart failure and acute atrial fibrillation received the final diagnosis of atrial infarction associated with ventricular infarction based on clinical findings of ischemia in association with atrial fibrillation and heart failure (mechanisms probably involved: contractile dysfunction and loss of atrial contribution). Although a transesophageal echocardiography, which could refine the diagnosis of anatomic abnormalities, was not performed, all evidence led to the diagnosis of atrial involvement. Electrocardiographic findings were consistent with Liu's major criterion 3. Therapy with digitalis, quinidine and angiotensin-converting enzyme inhibitors was chosen, as the patient had acute pulmonary edema. The use of beta-blockers and verapamil was restricted. No other complications, such as thrombo-embolism or atrial rupture, were noted.