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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.

Introducao Em 2000, Gussak et al., publicaram uma serie de casos em que taquiarritmias atriais, sincope e morte subita cardiaca (MSC) se associavam a um intervalo QT pronunciadamente curto, sendo os primeiros a correlacionar todos esses achados em uma sindrome. Desde entao, esforcos vem sendo realizados, a fim de melhor entender o comportamento e encontrar alternativas de tratamento para a sindrome do QT curto (SQTC); no entanto, esbarram na raridade da doenca, na dificuldade em estabelecer parâmetros diagnosticos e na [...]

Resumo 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

Introducao Em dezembro de 2019, foram relatados os primeiros casos da doenca causada pelo novo coronavirus (COVID-19), originarios de Wuhan, China. Desde a declaracao de pandemia em marco de 2020 por Organizacao Mundial da Saude (OMS), com disseminacao intercontinental, vivenciamos intensa busca por um tratamento seguro e eficaz. Estudos in vitro demonstraram algum efeito da cloroquina contra o novo coronavirus, intermediada pela glicosilacao dos receptores celulares de SARS-CoV e pelo aumento do pH endossomico, bloqueando a invasao celular pelo virus. [...]

OBJECTIVE To compare the prevalence of esophageal and periesophageal thermal injury in patients undergoing radiofrequency (RF) atrial fibrillation (AF) ablation using 8 mm tip catheters during three different esophageal protection strategies. METHODS Forty-five consecutive patients with paroxysmal or persistent AF underwent first ablation procedure, besides esophagogastroduodenoscopy (EGD) combined with radial endosonography (EUS) performed before and after the pulmonary vein (PV) isolation. Before the procedure, patients were randomly assigned to one of three esophageal lesion protection strategies: group I-without any protective or monitoring dispositive and limiting RF applications to 30 W for 20 seconds, in left atrium posterior wall (LAPW); group II-power and time of RF delivery, up to 50 W for 20 seconds at LAPW, limited by esophageal temperature monitoring; group III-applications of RF in LAPW with fixed power application of 50 W for 20 seconds during continuous esophageal cooling. RESULTS Baseline characteristics of patients were similar in all groups. The four PVs were isolated in 14 (93.3%), 13 (86.7%), and 15 (100%) patients, respectively in groups I, II, and III. The mean RF power was significantly higher (P

Introduction Since December 31, 2019, when China reported the appearance of cases of acute respiratory failure caused by a new species of coronavirus, SARS-CoV-2, which causes the disease called COVID-19, almost 20 million cases were confirmed, causing 726 thousand deaths worldwide. In Brazil, on August 8th, 2020, there was approximately 3 million cases and 100 thousand death by the disease. Its rapid spread, its high potential for hospitalization, and its high lethality, especially in the most fragile groups such as [...]

In the treatment of atrial fibrillation (AF), the most frequently sustained arrhythmia, with catheter ablation (CA) or electrical cardioversion (ECV), the periprocedural period is one of the most critical phases. Currently, the use of new direct action oral anticoagulants (DOAC) is increasingly frequent; however, in the real world, there are still few data on studies on the thrombus incidence in the left atrium (TrLA) or dense spontaneous contrast (DSC) on transesophageal echocardiogram (TEE).To evaluate the prevalence of events and association with risk factors in patients using DOACs. Primary objective: to analyze the prevalence of thrombus in the LA by TEE in patients using DOAC undergoing ECV/CA. Second, evaluate the association of comorbidities with the presence of thrombi and DSC.Retrospective cohort, single-center study with patients followed at the Arrhythmia Outpatient Unit (InCor-HCFMUSP). Patients indicated for procedures and using DOACs were selected, and their clinical/echocardiographic data were analyzed. A significance level of 5% was considered.354 patients were included, a total of 400 procedures, from March 2012-March 2018. Thrombus in the LA was found in 11 patients (2.8%), associated with advanced age (p=0.007) and higher CHA2DS2-VASc (plt;0.001) score. DSC in the LA before TEE was found in 29 patients (7.3%), with lower LVEF (plt;0.038) and greater LA dimension (plt;0.0001).The incidence of LA thrombus and DSC in patients using DOC in the context of AF ECV/CA, although small, is not negligible. Patients with higher CHA2DS2-VASc scores, especially older and with larger LA diameter, are more prone to these echocardiographic findings.No tratamento da fibrilação atrial (FA), a arritmia sustentada mais frequente, com ablação por cateter (ABL) ou cardioversão elétrica (CVE), o período periprocedimento é uma das fases mais críticas. Atualmente, o uso de novos anticoagulantes orais de ação direta (DOAC) é cada vez mais frequente, no entanto, no mundo real, ainda existem poucos dados de estudos sobre a incidência de trombo no átrio esquerdo (TrAE) ou contraste espontâneo denso (CE) no ecocardiograma transesofágico (ETE).Analisar a prevalência de TrAE, por ETE, em pacientes em uso de DOAC submetidos à CVE/ABL. Secundariamente: avaliar a associação de comorbidades com a presença de trombos e CE.Estudo de coorte retrospectivo, unicêntrico, com pacientes do Ambulatório de Arritmia (InCor-HCFMUSP). Foram selecionados e analisados dados clínicos e ecocardiográficos no prontuário da instituição de pacientes com indicação de procedimentos e em uso de DOACs. Considerado um nível de significância de 5%.Foram incluídos 354 pacientes, no total de 400 procedimentos, de março de 2012-março de 2018. TrAE foi encontrado em 11 pacientes (2,8%), associado com idade avançada (p=0,007) e CHA2DS2-VASc maior (plt;0,001). Foi encontrado CE no AE no procedimento antes da ETE em 29 pacientes (7,3%), com menor FEVE (plt;0,038) e maior dimensão do AE (plt;0,0001).A incidência de TrAE e CE em pacientes em uso de DOAC no contexto de CVE/ABL de FA, embora pequena, não é desprezível. Pacientes com escore CHA2DS2-VASc maior, principalmente mais idosos e com diâmetro do AE maior, são mais propensos a esses achados ecocardiográficos.

Introduction: The autonomous system plays an important role as a trigger of cardiac arrhythmias. Cardiac sympathetic denervation (CSD) achieved by stellate and proximal thoracic ganglia resection has been reported as an alternative approach for the management of ventricular arrhythmias (VA) in structural heart disease (SHD) patients. Insufficient data regarding Chagas Disease (ChD) is available. Methods: Patients who underwent CSD for better management of ventricular arrhythmias (VA) in SHD, mainly ChD, in a single tertiary center in Brazil were evaluated for safety and efficacy outcomes. Results: Between June 2014 and March 2020, fourteen patients (age 59±7.5, 85% male, mean ejection fraction 30.5±7.9%) were submitted to left or bilateral CSD. In a median follow-up time of 143 (Q1: 30; Q3: 374) days, eight patients (57,2%) presented VT recurrence. A significant reduction in the median burden of ventricular arrhythmias comparing six months before and after procedure (10 to 0; p=0.004). For the nine ChD patients, the median burden of appropriate therapies was also reduced (11 to 0; p=0.008). There were two cases of clinically relevant pneumothorax and three cases of transient hemodynamic instability, but no direct procedure-related deaths occurred. Additionally, there was no long-term adverse events, Conclusion: CSD is safe and seems to be effective in reducing the burden of VT/VT storm in SHD patients, including ChD patients. Randomized trials are needed to clarify its role in the management of these patients.

Resumo Fundamento O diagnóstico diferencial de taquicardia de QRS largo, entre taquicardia ventricular (TV) ou taquicardia supraventricular com condução aberrante (TSV-A) é algumas vezes difícil de ser feito na sala de emergência. Objetivo Avaliar a acurácia de um algoritmo novo e simples para a detecção de TV no eletrocardiograma (ECG) em pacientes com taquicardia de QRS largo. Métodos ECGs de 12 derivações para detecção de taquicardia de QRS largo foram obtidos prospectivamente de 120 pacientes durante estudo eletrofisiológico. Seis médicos com diferentes experiências analisaram os ECGs, e fizeram o diagnóstico com base no algoritmo D12V16, que envolve a análise da polaridade predominante do complexo QRS nas derivações I, II, V1 e V6. O diagnóstico foi comparado com os obtidos pelo algoritmo tradicional de Brugada e pelo estudo eletrofisiológico, o qual é considerado padrão ouro. Adotou-se um nível de significância de 5% (p

Weitere Verfasser:innen aus Einrichtungen außerhalb der Universität Duisburg-Essen sind nicht aufgeführt. In this article, the name of the GLORIA-AF investigator Anastasios Kollias was given incorrectly as Athanasios Kollias in the Acknowledgements. The original article has been corrected.

Background: Warfarin is the most commonly drug for oral anticoagulant therapy, especially in low-income and emerging countries, because of the high cost of the direct oral anticoagulant (DOACs) or when warfarin is the only proven therapy (mechanical prosthetic valve and kidney dysfunction). The beneficial outcomes of warfarin therapy are directly dependent on the quality of anticoagulation management and dose regimen. Studies showed that pharmacists could improve the effectiveness of therapy with warfarin. However, there are no studies showing this intervention in a specific patient group with poor quality of anticoagulation in a long period after the end of the follow-up by a pharmacist. Thus, the aim of this study was to evaluate whether the quality of warfarin therapy driven by a pharmacist remains in a long term after the end of follow up with pharmacist, in patients with AF and poor quality of anticoagulation. Methods: This is a prospective study which evaluated about 2,620 patients and selected 262 patients with AF and poor quality of anticoagulation therapy with warfarin (TTR

BACKGROUND Brugada syndrome (BrS) has diagnostic challenges and controversial risk assessment. We aimed to investigate invasive and noninvasive parameters in symptomatic and asymptomatic patients from a Brazilian cohort of type-1 BrS. METHODS Patients with spontaneous and drug-induced type-1 BrS were classified into two groups, asymptomatic (n = 116, 84.1%) and symptomatic (n = 22, 15.9%; 13 with arrhythmogenic syncope, 9 with aborted sudden cardiac death). Genetic testing, EPS parameters, and electrocardiogram (ECG) parameters were analyzed. RESULTS A total of 138 consecutive patients were eligible, 101 men (73.2%), mean 41.4 years, mostly probands (79%). Spontaneous pattern, observed in 77.5% of the patients, was associated with symptoms only if expressed in V1 and V2 standard position (not high precordial leads; p = .014). All symptomatic patients were probands. The presence of right ventricular outflow tract conduction delay (RVOTcd) signs, positive EPS, and SCN5A status was similar between symptomatic and asymptomatic subjects. During the mean 75-month follow-up, eight patients had appropriate therapies. All had spontaneous type-1 ECG pattern and 2/8 (25%) were asymptomatic, with positive EPS. The overall LAE incidence of 1.1% per year dropped to 0.27% in asymptomatic patients. RVOTcd occurred more frequently in SCN5A carriers (QRS-f 33.3% vs. 7.7%; p = .005, AVR sign 58.3% vs. 13.6%; p

International audience; Arrhythmogenic cardiomyopathy (ACM) is an arrhythmogenic disorder of the myocardium not secondary to ischemic, hypertensive, or valvular heart disease. ACM incorporates a broad spectrum of genetic, systemic, infectious, and inflammatory disorders. This designation includes, but is not limited to, arrhythmogenic right/left ventricular cardiomyopathy, cardiac amyloidosis, sarcoidosis, Chagas disease, and left ventricular noncompaction. The ACM phenotype overlaps with other cardiomyopathies, particularly dilated cardiomyopathy with arrhythmia presentation that may be associated with ventricular dilatation and/or impaired systolic function. This expert consensus statement provides the clinician with guidance on evaluation and management of ACM and includes clinically relevant information on genetics and disease mechanisms. PICO questions were utilized to evaluate contemporary evidence and provide clinical guidance related to exercise in arrhythmogenic right ventricular cardiomyopathy. Recommendations were developed and approved by an expert writing group, after a systematic literature search with evidence tables, and discussion of their own clinical experience, to present the current knowledge in the field. Each recommendation is presented using the Class of Recommendation and Level of Evidence system formulated by the American College of Cardiology and the American Heart Association and is accompanied by references and explanatory text to provide essential context. The ongoing recognition of the genetic basis of ACM provides the opportunity to examine the diverse triggers and potential common pathway for the development of disease and arrhythmia.

Background Brugada syndrome and long‐QT syndrome may account for at least one third of unexplained sudden cardiac deaths. Dental care in patients with cardiac channelopathies is challenging because of the potential risk of life‐threatening events. We hypothesized that the use of local dental anesthesia with lidocaine with and without epinephrine is safe and does not result in life‐threatening arrhythmias in patients with channelopathies. Methods and Results We performed a randomized, double‐blind pilot trial comparing the use of 2% lidocaine without a vasoconstrictor and with 1:100 000 epinephrine in 2 sessions of restorative dental treatment with a washout period of 7 days (crossover trial). Twenty‐eight–hour Holter monitoring was performed, and 12‐lead electrocardiography, digital sphygmomanometry, and anxiety scale assessments were also conducted at 3 time points. Fifty‐six dental procedures were performed in 28 patients (18 women, 10 men) with cardiac channelopathies: 16 (57.1%) had long‐QT syndrome, and 12 (42.9%) had Brugada syndrome; 11 (39.3%) of patients had an implantable defibrillator. The mean age was 45.9±15.9 years. The maximum heart rate increased after the use of epinephrine during the anesthesia period from 82.1 to 85.8 beats per minute ( P =0.008). In patients with long‐QT syndrome, the median corrected QT was higher, from 450.1 to 465.4 ms ( P =0.009) at the end of anesthesia in patients in whom epinephrine was used. The other measurements showed no statistically significant differences. No life‐threatening arrhythmias occurred during dental treatment. Conclusions The use of local dental anesthesia with lidocaine, regardless of the use of a vasoconstrictor, did not result in life‐threatening arrhythmias and appears to be safe in stable patients with cardiac channelopathies. Clinical Trial Registration URL: http://www.clinicaltrials.gov . Unique identifier: NCT03182777.

International audience; Arrhythmogenic cardiomyopathy (ACM) is an arrhythmogenic disorder of the myocardium not secondary to ischemic, hypertensive, or valvular heart disease. ACM incorporates a broad spectrum of genetic, systemic, infectious, and inflammatory disorders. This designation includes, but is not limited to, arrhythmogenic right/left ventricular cardiomyopathy, cardiac amyloidosis, sarcoidosis, Chagas disease, and left ventricular noncompaction. The ACM phenotype overlaps with other cardiomyopathies, particularly dilated cardiomyopathy with arrhythmia presentation that may be associated with ventricular dilatation and/or impaired systolic function. This expert consensus statement provides the clinician with guidance on evaluation and management of ACM and includes clinically relevant information on genetics and disease mechanisms. PICO questions were utilized to evaluate contemporary evidence and provide clinical guidance related to exercise in arrhythmogenic right ventricular cardiomyopathy. Recommendations were developed and approved by an expert writing group, after a systematic literature search with evidence tables, and discussion of their own clinical experience, to present the current knowledge in the field. Each recommendation is presented using the Class of Recommendation and Level of Evidence system formulated by the American College of Cardiology and the American Heart Association and is accompanied by references and explanatory text to provide essential context. The ongoing recognition of the genetic basis of ACM provides the opportunity to examine the diverse triggers and potential common pathway for the development of disease and arrhythmia.

// Leiliane Rodrigues Marcatto 1,* , Luciana Sacilotto 2,* , Francisco Carlos da Costa Darrieux 2 , Denise Tessariol Hachul 2 , Mauricio Ibrahim Scanavacca 2 , Jose Eduardo Krieger 1 , Alexandre Costa Pereira 1 and Paulo Caleb Junior Lima Santos 1 1 Laboratory of Genetics and Molecular Cardiology, Heart Institute (InCor), University of Sao Paulo Medical School, Sao Paulo, Brazil 2 Clinical Cardiology Division, Heart Institute (InCor), University of Sao Paulo Medical School, Sao Paulo, Brazil * These authors have contributed equally to this work Correspondence to: Alexandre Costa Pereira, email: // Paulo Caleb Junior Lima Santos, email: // Keywords : warfarin, TTR, age, atrial fibrillation, polymorphisms, Gerotarget Received : May 03, 2016 Accepted : July 19, 2016 Published : July 29, 2016 Abstract Background: Warfarin is the most prescribed oral anticoagulant used for preventing stroke in patients with atrial fibrillation. Time in the therapeutic range (TTR) has been accepted as the best method to evaluate the quality of warfarin therapy. The main aim of the present study was to evaluate the impact of variables on the time in the therapeutic range for warfarin therapy in patients with atrial fibrillation from a referral cardiovascular hospital. Methods: This retrospective study included 443 patients were included (190 patients with age < 65 years and 253 patients with age ≥65 years) from 2011 to 2014 and TTR was computed according to Rosendaal’s method. Results: Patients with age ≥65 years had higher TTR value (67±22%) compared with patients with < 65 years (60±24%) ( p = 0.004). In a linear regression model, only age ≥65 years emerged as a significant predictor of greater TTR values. In multivariate logistic regression model, the variable age ≥65 years was associated with higher OR for having a TTR higher than the median value (OR = 2.17, p < 0.001). Conclusion: We suggest that the age influenced TTR through greater drug adherence. Strategies for increasing drug adherence might improve quality of warfarin anticoagulation.

Thromboembolic events are associated with high mortality and morbidity indexes. In this context, warfarin is the most widely prescribed oral anticoagulant agent for preventing and treating these events. This medication has a narrow therapeutic range and, consequently, patients usually have difficulty in achieving and maintaining stable target therapeutics. Some studies on the literature about oral anticoagulant management showed that pharmacists could improve the efficiency of anticoagulant therapy. However, the majority of these studies included general patients retrospectively. The aim of this study was to prospectively evaluate a pharmacist’s warfarin management in patients with poor quality of anticoagulation therapy (Time in the Therapeutic Range- TTR < 50%). We included 268 patients with atrial fibrillation (AF) and without stable dose of warfarin (TTR < 50%, based on the last three values of International Normalized Ratio-INR). We followed them up for 12 weeks, INR values were evaluated and, when necessary, the dose adjustments were performed. During the first four visits, patient’s INR was measured every 7 days. Then, if INR was within the target therapeutic range (INR: 2–3), the patient was asked to return in 30 days. However, if INR was out the therapeutic target, the patient was asked to return in 7 days. Adherence evaluation was measured through questionnaires and by counting the pills taken. Comparison between basal TTR (which was calculated based on the three last INR values before prospective phase) and TTR of 4 weeks (calculated by considering the INR tests from visits 0 to 4, in the prospective phase of the study) and basal TTR and TTR of 12 weeks (calculated based on the INR tests from visits 0 to 12, in the prospective phase of the study) revealed significant statistical differences (0.144 ± 0.010 vs. 0.382 ± 0.016; and 0.144 ± 0.010 vs. 0.543 ± 0.014, p < 0.001, respectively). We also observed that the mean TTR of 1 year before (retrospective phase) was lower than TTR value after 12 weeks of pharmacist-driven treatment (prospective phase) (0.320 ± 0.015; 0.540 ± 0.015, p < 0.001). In conclusion, pharmaceutical care was able to improve TTR values in patients with AF and poor quality of anticoagulation with warfarin.

Background: Carotid sinus hypersensitivity (CSH) is a frequent finding in the evaluation of syncope. However, its significance in the clinical setting is still dubious. A new criterion was proposed by Solari et al. with a symptomatic systolic blood pressure (SBP) cut-off value of ≤ 85 mmHg to refine the vasodepressor (VD) response diagnosis. Objective: To determine and compare the response to carotid sinus massage (CSM) in patients with and without syncope according to standard and proposed criteria. Methods: CSM was performed in 99 patients with and 66 patients without syncope. CSH was defined as cardioinhibitory (CI) for asystole ≥ 3 seconds, or as VD for SBP decrease ≥ 50 mmHg. Results: No differences in the hemodynamic responses were observed during CSM between the groups, with 24.2% and 25.8% CI, and 8.1% and 13.6% VD in the symptomatic and asymptomatic groups, respectively (p = 0.466). A p value < 0.050 was considered statistically significant. During the maneuvers, 45 (45.45%) and 34 (51.5%) patients in the symptomatic and asymptomatic groups achieved SBP below ≤ 85 mmHg. Symptoms were reported especially in those patients in whom CSM caused a SBP decrease to below 90 mmHg and/or asystole > 2.5 seconds, regardless of the pattern of response or the presence of previous syncope. Conclusion: The response to CSM in patients with and without syncope was similar; therefore, CSH may be an unspecific condition. Clinical correlation and other methods of evaluation, such as long-lasting ECG monitoring, may be necessary to confirm CSH as the cause of syncope. Resumo Fundamento: A hipersensibilidade do seio carotídeo (HSC) é um achado frequente na avaliação da síncope. Entretanto, o valor da resposta positiva é ainda incerto no contexto clínico. Novo critério diagnóstico para tentar refinar a resposta vasodepressora (VD) foi proposto por Solari et al. com determinação da queda sintomática da pressão arterial sistólica (PAS) a níveis ≤ 85 mmHg como ponto de corte. Objetivo: Determinar e comparar a resposta à massagem do seio carotídeo (MSC) em pacientes com e sem síncope de acordo com os critérios vigentes e propostos. Métodos: A MSC foi realizada em 99 pacientes com síncope e 66 pacientes sem síncope. A HSC foi definida como cardioinibitória (CI), se assistolia ≥ 3 segundos, ou VD, se queda da PAS ≥ 50 mmHg. Resultados: Não foram observadas diferenças na resposta hemodinâmica entre os grupos durante a MSC, com 24,2% e 25,8% de resposta CI, e 8,1% e 13,6% de resposta VD nos grupos sintomático e assintomático, respectivamente (p = 0,466). Considerou-se p < 0,05 estatisticamente significativo. Durante as manobras, 45 (45,45%) e 34 (51,5%) pacientes nos grupos sintomático e assintomático atingiram PAS ≤ 85 mmHg. Sintomas foram relatados principalmente por pacientes em que a MSC reduziu a PAS para menos de 90 mmHg e/ou causou assistolia > 2,5 segundos, independentemente do padrão da resposta ou história de síncope prévia. Conclusão: As respostas à MSC em pacientes com e sem síncope foram semelhantes. Portanto, a HSC pode ser uma condição inespecífica. A correlação clínica mais precisa e outros métodos para avaliação, como monitoramento por ECG de longa duração, podem ser necessários para confirmação da HSC como causa da síncope.

Aim Acute and subacute cardiotoxicity are characterized by prolongation of the corrected QT interval (QTc) and other measures derived from the QTc interval, such as QTc dispersion (QTdc) and transmural dispersion of repolarization (DTpTe). Although anthracyclines prolong the QTc interval, it is unclear whether breast cancer patients who undergo the ACT chemotherapy regimen of anthracycline (doxorubicin: A), cyclophosphamide (C) and taxane (T) may present with QTc, QTdc and DTpTe prolongation. Methods Twenty-three consecutive patients with breast cancer were followed prospectively during ACT chemotherapy and were analyzed according to their QT measurements. QTc, QTdc and DTpTe measurements were determined by a 12-lead electrocardiogram (EKG) prior to chemotherapy (baseline), immediately after the first phase of anthracycline and cyclophosphamide (AC) treatment, and immediately after T treatment. Serum troponin and B-type natriuretic peptide (BNP) levels were also measured. Results Compared to baseline values, the QTc interval was significantly prolonged after the AC phase (439.7 ± 33.2 ms vs. 472.5 ± 36.3 ms, p = 0.001) and after T treatment (439.7 ± 33.2 ms vs. 467.9 ± 42.6 ms, p < 0.001). Troponin levels were elevated after the AC phase (23.0 pg/mL [min-max: 6.0–85.0] vs. 6.0 pg/mL [min-max: 6.0–22.0], p < 0.001) and after T treatment (25.0 pg/mL [min-max: 6.0–80.0] vs. 6.0 pg/mL [min-max: 6.0–22.0], p < 0.001) compared to baseline values. Conclusion In this prospective study of patients with non-metastatic breast cancer who underwent ACT chemotherapy, significant QTc prolongation and an elevation in serum troponin levels were observed.

Background:Ventricular and supraventricular premature complexes (PC) are frequent and usually symptomatic. According to a previous study, magnesium pidolate (MgP) administration to symptomatic patients can improve the PC density and symptoms.Objective:To assess the late follow-up of that clinical intervention in patients treated with MgP or placebo.Methods:In the first phase of the study, 90 symptomatic and consecutive patients with PC were randomized (double-blind) to receive either MgP or placebo for 30 days. Monthly follow-up visits were conducted for 15 months to assess symptoms and control electrolytes. 24-hour Holter was performed twice, regardless of symptoms, or whenever symptoms were present. In the second phase of the study, relapsing patients, who had received MgP or placebo (crossing-over) in the first phase, were treated with MgP according to the same protocol.Results:Of the 45 patients initially treated with MgP, 17 (37.8%) relapsed during the 15-month follow-up, and the relapse time varied. Relapsing patients treated again had a statistically significant reduction in the PC density of 138.25/hour (p < 0.001). The crossing-over patients reduced it by 247/hour (p < 0.001). Patients who did not relapse, had a low PC frequency (3 PC/hour). Retreated patients had a 76.5% improvement in symptom, and crossing-over patients, 71.4%.Conclusion:Some patients on MgP had relapse of symptoms and PC, indicating that MgP is neither a definitive nor a curative treatment for late follow-up. However, improvement in the PC frequency and symptoms was observed in the second phase of treatment, similar to the response in the first phase of treatment. Fundamento:Extrassístoles (ES) ventriculares e supraventriculares são frequentes e muitas vezes sintomáticas. Segundo estudo prévio, a administração de pidolato de magnésio (PMg) a pacientes sintomáticos pode resultar na melhora da densidade das ES e dos sintomas relacionados.Objetivo:Avaliar os resultados dessa intervenção clínica inicial no seguimento tardio de pacientes recebendo PMg ou placebo.Métodos:Noventa pacientes com ES, sintomáticos e consecutivos foram randomizados (duplo-cego) para receber PMg ou placebo por 30 dias. Visitas mensais de seguimento (15 meses) foram realizadas para avaliar a sintomatologia e controlar eletrólitos. O Holter de 24 horas foi realizado sempre que sintomáticos, ou duas vezes, independentemente dos sintomas. Na segunda fase do estudo, os pacientes cujos sintomas recidivassem, seja do grupo PMg ou placebo (crossing over), receberam PMg seguindo-se o mesmo protocolo.Resultados:Dos 45 pacientes que receberam inicialmente o PMg, 17 (37,8%) apresentaram recidiva dos sintomas em tempo variável nos 15 meses. Os pacientes com recidiva e tratados uma segunda vez apresentaram redução estatisticamente significante na densidade de ES de 138,25/hora (p < 0,001). Os pacientes de crossing reduziram em 247/hora (p < 0,001). Nos pacientes que não apresentaram recidiva, a frequência de ES foi baixa (3 ES/hora). A melhora dos sintomas foi de 76,5% nos retratados e de 71,4% nos de crossing.Conclusão:Houve recorrência de sintomas e das ES em alguns pacientes que usaram PMg, deixando claro não ser essa uma forma de tratamento definitivo ou curativo no seguimento tardio. Contudo, houve também melhora na frequência de ES e de sintomas em uma segunda etapa de tratamento, semelhante à resposta na primeira etapa.

The association between Brugada syndrome (BS) and ventricular preexcitation is a rare condition, with sporadic cases already reported. We report the case of a 29-year-old man, with palpitation unrelated to physical or emotional stress. The electrocardiogram of the first visit revealed a ventricular preexcitation pattern and an end-conduction delay, with negative T wave in V1 and intraventricular conduction disturbance in V2 (atypical for BS). The typical aspect of BS occurred after introduction of propafenone for the prevention of atrioventricular tachycardia. We discuss the recognition of this rare association, the proarrhythmic effects of some drugs, treatment options, and prognosis.

"Torsades de pointes" (TdP) ventricular tachycardias carry a high risk of sudden death, even when they occur in individuals with a structurally normal heart, in the absence of myocardial ischemia or prolonged QT interval. Leenhardt et al1 described a new syndrome with these characteristics in 1994 that showed a difference in which the TdP were triggered by ventricular extrasystoles (VE) with ultra-short coupling interval (< 300 ms). Although this condition is easily diagnosed by the described characteristics, there is a lack of data on the clinical management of patients during the phase of electrical storm and during long-term clinical outcome. Over the past 20 years, three patients were identified in our institution with this clinical condition, as well as a family member with VE and short coupling interval, asymptomatic and without documented polymorphic ventricular tachycardia (VT). The aim of this case report is to describe the clinical management used in these patients and review the literature on the implication of the finding of VE with short coupling interval in asymptomatic family members.

Background Time in therapeutic range (TTR) is a measurement of quality of warfarin therapy and lower TTR values (

Background— Autonomic denervation is an alternative approach for patients with symptomatic bradycardia. No consensus exists on the critical targets and end points of the procedure. The aim of this study was to identify immediate end points and critical atrial regions responsible for vagal denervation. Methods and Results— We enrolled 14 patients (50% men; age: 34.0±13.8 years) with cardioinhibitory syncope, advanced atrioventricular block or sinus arrest, and no structural heart disease. Anatomic mapping of ganglionated plexuses was performed, followed by radiofrequency ablation. Heart rate, sinus node recovery time, Wenckebach cycle length, and atrial-His (AH) interval were measured before and after every radiofrequency pulse. Wilcoxon signed-rank test was used for comparison. Significant shortening of the R-R interval ( P =0.0009), Wenckebach cycle length ( P =0.0009), and AH intervals ( P =0.0014) was observed after ablation. The heart rate elevation was 23.8±12.5%, and the Wenckebach cycle length and AH interval shortening was 18.1±11% and 24.6±19%, respectively. Atropine bolus injection (0.04 mg/kg) did not increase heart rate further. Targeting a single spot of the left side (64% of the patients) or right side (36%) of the interatrial septum was observed to be responsible for ≥80% of the final R-R and AH interval shortening during ablation. Conclusions— Targeting specific sites of the interatrial septum is followed by an increase in heart rate and atrioventricular nodal conduction properties and might be critical for vagal attenuation. The R-R interval, Wenckebach cycle length, and AH interval shortening, associated with a negative response to atropine, could be considered immediate end points of the procedure.

Atrial fibrillation (AF) is the sustained arrhythmia most frequently found in clinical practice. Its prevalence is expected to increase in the coming decades. Its occurrence implies a reduction in the quality of life and an increase in mortality, mainly due to stroke and systemic thromboembolism (TE). The stroke originating from AF carries a higher risk of severe complications, such as permanent disability and prolonged hospitalization, as compared to that of other etiologies.1-3 Since the discovery of vitamin K (VitK) antagonists more than 50 years ago, they have become the most effective treatment to prevent stroke and TE in patients with AF. However, because of the risk of hemorrhagic complications they pose, only patients with persistent AF considered of very high risk, previous embolic accidents, mechanical valvular prostheses, and those undergoing electrical cardioversion used to receive that treatment in an initial phase. Between the 1980 and 1990 decades, major clinical controlled studies determining the importance of stroke prevention in non-valvular AF were carried out, providing scientific support to the current clinical use of VitK antagonists. The greater benefit of the VitK antagonists as compared to placebo (a mean 64% reduction in relative risk) has been undoubtedly demonstrated, as has been the modest or even absent role of acetylsalicylic acid in stroke prevention in that population.4 Despite that evidence, the clinical use of VitK antagonists remained very limited over the following years, because of their complex pharmacokinetics and pharmacodynamics. Undesirable drug interactions and their narrow therapeutic window (borderline between efficacy in embolism prevention and risk of bleeding) are the major limitations of their use and the reason for the need to monitor often the anticoagulation level.5-7 On the other hand, the advances in knowing the risk factors for the formation of AF-related atrial thrombus and embolism and the risk of bleeding due to VitK antagonists have motivated the development of new strategies based on the risk-benefit ratio of using anticoagulants to prevent stroke.8-11 The major risk scores currently used are CHA2DS2VASc for embolism, and HASBLED for bleeding. The balance between those two scores has made the use of anticoagulants easier. Nevertheless, VitK antagonists have been underused in clinical practice. Real world studies have shown that only 50% of the patients with indication for their use received medical recommendation, and only 50% of them (specially in Brazil) had proper INR control.12-14 Aiming at a better safety profile, with fewer drug and food interactions, non-VitK antagonist oral anticoagulants, the "novel oral anticoagulants" (NOACs), have been developed. Dabigatran, a direct thrombin inhibitor, was the first NOAC registered and approved by the major drug regulatory agencies around the world, based on the results of the RE-LY study in 2009.15 Subsequently, NOACs belonging to the family of activated factor X inhibitors were developed, being approved for clinical use by the major drug regulatory agencies around the world after the publication of the following studies: ROCKET-AF (rivaroxaban);16 ARISTOTLE (apixaban);17 and, more recently, ENGAGE (edoxaban).18 Considering the high efficacy of warfarin as compared to placebo and acetylsalicylic acid to prevent TE phenomena, those four studies were designed for the non-inferiority hypothesis. The results obtained with a large number of patients (70,000) have shown that NOACs are at least non-inferior to warfarin regarding efficacy. On the other hand, an unequivocal comparison could not be established between the different NOACs, because the studies are not identical. On indirect analysis, dabigatran at the dose of 150 mg, twice a day, and apixaban at the dose of 5 mg, twice a day, stood out, showing superiority over warfarin in reducing total stroke. Regarding safety, all NOACs were superior to warfarin in reducing hemorrhagic stroke and potentially fatal hemorrhages. Rivaroxaban and edoxaban stood out because of their convenient administration, with just one daily intake. Based on those clinical studies, the European Guideline of Cardiology recommends any NOAC (dabigatran, apixaban, rivaroxaban) as an alternative to VitK antagonists in patients with non-valvular AF19 The American guideline for the management of patients with AF recommends VitK antagonists as class IA and the NOACs (apixaban, dabigatran and rivaroxaban) as class IB for patients with non-valvular AF and risk factors for stroke and systemic embolism.20 Real world observations have reproduced the initial clinical studies, confirming that NOACs are an effective alternative for stroke/TE prevention in patients with AF,21 being also recommended by the Brazilian Society of Cardiology guideline on anticoagulation.22 This wider range of choice, however, generates natural questioning about the current role of VitK antagonists. Two aspects have guided the selection of anticoagulants in this transition phase, in which clinicians acquire experience with the new drugs, comparing them with those traditionally used: 1) technical questions, related to drug efficacy and safety; and 2) the possibility that the patients pay for their treatment or have it paid for by health care services. Regarding the technical question, the advantages of warfarin are as follows: 1) it is the one and only drug with proven efficacy in patients with mitral stenosis, patients with metal valve prostheses and renal failure; 2) greater experience over decades (50 years of use); 3) the physician follows the effectiveness or risk of the treatment by controlling INR; 4) easily maintained treatment because of the low cost of the medication; 5) possibility of effect attenuation by administrating vitK or blood derivative products; and 6) prolonged therapeutic effect, so that skipping one dose usually does not interfere with the therapeutic activity. Regarding the technical question, the advantages of the NOACs are as follows: 1) rapid onset and end of their anticoagulant effect; 2) they usually do not require transition with low-molecular-weight heparin; 3) low drug interaction; 4) no food interaction; 5) important reduction in the risk for hemorrhagic stroke; and 6) smaller necessity for periodical laboratory control (although anticoagulation control is not recommended, regular renal function monitoring is still required). There are some gray areas in the use and indication of NOACs, such as the procedures of cardioversion and ablation and the context of acute coronary disease, and the interventions with bare-metal and drug-eluting stent implantation. Regarding the cardioversions for AF, the substudies RE-LY, ARISTOTLE and ROCKET-AF have shown similar effectiveness between NOACs and VitK inhibitors, an observation confirmed by the X-VeRT trial, which randomized rivaroxaban and VitK antagonists in patients with AF undergoing cardioversion.23 Regarding AF ablation, isolated studies have shown that NOACs are usually effective and safe, depending on the type of protocol used. There are new ongoing studies to define the best strategy for patients in that condition. Regarding patients with AF in the context of acute coronary disease, recently or during hemodynamic interventions, prospective studies on NOACs are awaited. The subanalyses of previous multicenter studies have not authorized the unrestricted use of NOACs in those patients, warfarin being the most often studied drug, in double or triple combination with antiplatelet agents. However, there are "recommendations" for the early use of NOACs at their lowest dose studied (rivaroxaban 15 mg, once a day; dabigatran 110 mg, twice a day; or apixaban 2.5 mg, twice a day) in association with an antiplatelet agent, preferably clopidogrel.19 The future results of the studies conducted with that purpose will or will not support the current orientation. A very important aspect for the incorporation of NOACs is their cost, much higher than that of VitK antagonists. This has relevant clinical implications, because their suspension, even if transient, places the patient at risk for embolic events due to the rapid loss of their anticoagulant effects and the possibility of paradoxical hypercoagulability. In the social context, most patients treated at public hospitals receive VitK antagonists. The incorporation of new anticoagulants should promote a significant impact on the budget of those hospitals.24,25 Therefore, Brazilian studies assessing the local needs and the clinical and financial impact of the introduction of those new therapeutic strategies in patients with AF are required. In addition, it is worth noting that, while that cost/effectiveness ratio has not been clarified, the prevention of embolism in AF by using VitK antagonists is well established, and the maintenance of INR within the therapeutic range promotes efficacy levels equivalent to those of NOACs. In conclusion, the knowledge acquired with the management of VitK antagonists over the years allows us to glimpse a horizon of opportunities to use NOACs to perfect the prevention of TE phenomena in patients with AF. The comfort provided by NOACs, by not requiring anticoagulation level monitoring, however, should not be interpreted as no need for drug surveillance and for periodical care of the patient as a whole. Further clinical studies conducted in Brazil are required to allow the identification of patients' profiles more favorable to each of those new drugs, considering a good cost/effectiveness ratio.

FUNDAMENTO: Ablação por radiofrequência (ARF) em crianças consiste em uma prática cada vez mais frequente. OBJETIVO: Avaliar, em nossa instituição, os resultados da ARF em crianças com idade abaixo de 15 anos. MÉTODOS: Foram analisadas 125 crianças submetidas à ARF entre maio de 1991 a maio de 2010. RESULTADOS: Sessenta e sete (53,6%) crianças eram do sexo masculino, com idade entre 44 dias e 15 anos (média de 8,6 ± 3,3 anos) e peso mediano de 31 kg. Cardiopatia esteve presente em 21 (16,8%) pacientes. A ARF de vias acessórias (VA) foi o procedimento mais comum (62 crianças - 49,6%). A ARF de taquicardias por reentrada nodal (TRN) foi a segunda arritmia mais frequente, em 27 (21,6%), seguida de taquicardias atriais (TA), em 16 (12,8%) e de taquicardias ventriculares (TV) em 8 (6,4%) crianças. Os critérios de sucesso foram alcançados em 86,9%, 96,1%, 80% e 62,5% dos pacientes submetidos à ARF de VA, TRN, TA e TV, respectivamente. Os bloqueios atrioventriculares transitórios (BAVT) ocorreram durante a ARF em 4 (3,2%) e BRD em 7 (5,6%) crianças. Vinte e cinco crianças foram submetidos à nova ARF por insucesso inicial ou recorrência. Durante o seguimento médio de 5,5 ± 3,4 anos, 107 (88,4%) persistiram sem recorrência. Não houve diferença estatística em relação aos resultados e à idade em que o paciente se submeteu ao procedimento. Nenhuma criança apresentou BAVT persistente ou necessitou de marca-passo definitivo. CONCLUSÃO: A ablação por cateter é uma alternativa terapêutica segura e eficiente em crianças com taquicardias recorrentes refratárias ao tratamento clínico.

FUNDAMENTO: As extrassístoles ventriculares e supraventriculares (EV e ESSV) são frequentes e muitas vezes sintomáticas. O íon magnésio (Mg) desempenha um papel importante na fisiologia do potencial de ação transmembrana celular e do ritmo cardíaco. OBJETIVO: Avaliar se a administração do pidolato de magnésio (PMg) em pacientes com EV e ESSV tem desempenho superior ao uso do placebo (P) na melhora dos sintomas e densidade das extrassístoles (DES). MÉTODOS: Estudo duplo-cego, randomizado, com 60 pacientes sintomáticos consecutivos, com mais de 240/EV ou ESSV ao Holter de 24 horas e selecionados para receber P ou PMg. Para avaliar a melhora da sintomatologia, foi feito um questionário categórico e específico de sintomas relacionados às extrassístoles. Após o tratamento, foi considerada significante uma redução de mais de 70% na DES por hora. A dose do PMg foi de 3,0 g/dia por 30 dias, equivalente a 260 mg do elemento Mg. Nenhum paciente tinha cardiopatia estrutural ou insuficiência renal. RESULTADOS: Dos 60 pacientes estudados, 33 eram do sexo feminino (55%). A faixa etária variou de 16 a 70 anos. No grupo PMg, 76,6% dos pacientes tiveram redução maior que 70%, 10% deles maior que 50% e somente 13,4% tiveram redução menor que 50% na DES. No grupo P, 40% dos pacientes tiveram melhora de apenas 30% na frequência de extrassístoles (p < 0,001). A melhora dos sintomas foi alcançada em 93,3% dos pacientes do grupo PMg, comparada com somente 16,7% do grupo P (p < 0,001). CONCLUSÃO: A suplementação de Mg via oral reduziu a DES, resultando em melhora dos sintomas. BACKGROUND: Premature ventricular and supraventricular complexes (PVC and PsVC) are frequent and often symptomatic. The magnesium (Mg) ion plays a role in the physiology of cell membranes and cardiac rhythm. OBJECTIVE: We evaluated whether the administration of Mg Pidolate (MgP) in patients with PVC and PsVC is superior to placebo (P) in improving symptoms and arrhythmia frequency. METHODS: Randomized double-blind study with 60 consecutive symptomatic patients with more than 240 PVC or PsVC on 24-hour Holter monitoring who were selected to receive placebo or MgP. To evaluate symptom improvement, a categorical and a specific questionnaire for symptoms related to PVC and PsVC was made. Improvement in premature complex density (PCD) per hour was considered significant if percentage reduction was >70% after treatment. The dose of MgP was 3.0 g/day for 30 days, equivalent to 260mg of Mg element. None of the patients had structural heart disease or renal failure. RESULTS: Of the 60 patients, 33 were female (55%). Ages ranged from 16 to 70 years old. In the MgP group, 76.6% of patients had a PCD reduction >70%, 10% of them >50% and only 13.4%

The use of cardiac MRI has been an interesting tool to substrate identification and ablation planning. ADAS software has been developed to identify conducting channels using 3D LGE MRI. Chagas disease is an infectious disease that lead to specific abnormalities that are substrate to scar related VT