Management of asymptomatic arrhythmias: a European Heart Rhythm Association (EHRA) consensus document, endorsed by the Heart Failure Association (HFA), Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), Cardiac Arrhythmia Society of Southern Africa (CASSA), and Latin America Heart Rhythm Society (LAHRS).

Asymptomatic arrhythmias are frequently encountered in clinical practice. Although studies specifically dedicated to these asymptomatic arrhythmias are lacking, many arrhythmias still require proper diagnostic and prognostic evaluation and treatment to avoid severe consequences, such as stroke or systemic emboli, heart failure, or sudden cardiac death. The present document reviews the evidence, where available, and attempts to reach a consensus, where evidence is insufficient or conflicting.

Miocardiopatía hipertrófica, anomalía coronaria, enfermedad aterosclerótica y arritmia ventricular coexistiendo en un mismo paciente / Joint presence of hypertrophic cardiomyopathy, anomalous origin of the circumflex coronary artery and ventricular arrhythmia

Presentamos el caso de un paciente quien presentó un evento presincopal en el que destacan 3 patologías asociadas a muerte súbita de forma independiente: miocardiopatía hipertrófica, origen anómalo coronario y enfermedad arterial coronaria epicárdica; diagnósticos coexistentes. Se describe las patologías, diagnóstico, manejo médico y terapéutico y se revisa la literatura.

A patient presented with a presyncopal event. Three conditions independently associated with sudden death, hypertrophic cardiomyopathy, anomalous origin of coronary arteries and epicardial coronary artery disease were found. Diagnosis, and medical management are described, followed by a review of the literature.

Ablación con RF de arritmia ventricular en paciente con disyunción anular mitral y QT prolongado / Radiofrequency ablation of ventricular arrhythmia in a patient with mitral annular disjunction and prolonged QT

Se presenta el caso de una mujer joven con arritmia ventricular compleja, disyunción anular mitral y QT largo. Se muestran los aspectos más relevantes de su presentación clínica, estudio, tratamiento y evolución. Se acompaña una revisión de la literatura.

We present the case of a young woman with complex ventricular arrhythmia, mitral annular disjunction and long QT. The most relevant aspects of its clinical presentation, study, treatment and evolution are shown. A review of the literature is included.

ablación de fibrilación auricular como tratamiento de primera línea: revisión de la literatura / Ablation as a first line treatment for atrial fibrillation: a review

RESUMEN La ablación con radiofrecuencia (RF) o con Criobalón (CRIO) en pacientes con fibrilación auricular (FA) paroxística y persistente es un tratamiento seguro y eficaz en pacientes seleccionados. Datos recientes demuestran que la ablación proporciona mejores resultados en comparación con fármacos antiarrítmicos (FAA) en el tratamiento de la FA temprana. Los estudios que comparan RF y CRIO mostraron una eficacia y seguridad comparables en el aislamiento de venas pulmonares (PVI) para pacientes con FA paroxística sintomática. OBJETIVOS: Revisar estudios clínicos que comparan el tratamiento de la FA con ablación versus FAA como terapia de primera línea en pacientes con FA sin tratamiento previo. La eficacia y la seguridad se compararán entre las dos cohortes y entre los subgrupos. MÉTODO: Se incluye un total de 6 estudios en los que participaron 1212 pacientes con FA: 609 pacientes fueron aleatorizados a ablación de FA y 603 a tratamiento farmacológico En comparación con el tratamiento con FAA, la ablación se asoció con una reducción en la recurrencia de arritmias auriculares (32,3 % frente a 53 %; riesgo relativo [RR], 0,62; IC del 95 %, 0,51-0,74; P < 0,001; I 2 = 40 %, NNT: 5). El uso de ablación también se asoció con una reducción de las arritmias auriculares sintomáticas (11,8 % frente a 26,4 %; RR, 0,44; IC del 95 %, 0,27-0,72; P = 0,001; I 2 = 54%) y hospitalización (5,6% vs 18,7%; RR, 0,32; IC 95%, 0,19-0,53; P< 0,001) sin diferencias significativas en los eventos adversos graves entre los grupos (4,2 % frente a 2,8 %; RR, 1,52; IC del 95 %, 0,81-2,85; P = 0,19). CONCLUSIÓN: En pacientes con FA paroxística, una estrategia de control precoz del ritmo cardíaco, se asocia con una mayor probabilidad de supervivencia, menos procedimientos repetidos, menos hospitalizaciones y, probablemente, una disminución en la progresión a FA persistente.

INTRODUCTION: Radiofrequency (RF) or cryoballoon (CRYO) ablation in patients with paroxysmal and persistent atrial fibrillation (AF) are safe and effective treatments in selected patients. Recent data show that ablation provides better results compared to antiarrhythmic drugs (AAD) in the treatment of early AF. Studies comparing RF and CRYO showed comparable efficacy and safety in pulmonary vein isolation (PVI) for patients with symptomatic paroxysmal AF. OBJETIVES: Review of clinical trials comparing treatment of AF with ablation versus AAD as first-line therapy in patients with AF with no previous treatment. Efficacy and safety are compared between the two cohorts and between subgroups. METHODS: A total of 6 studies involving -212 AF patients were included: 609 were randomized to AF ablation and 603 to pharmacological treatment. Ablation, compared with AAD, was associated with a reduction in recurrence of atrial arrhythmias (32.3% vs. 53%; relative risk [RR], 0.62; 95% CI, 0.51-0.74, P< 0.001, I2 = 40%, NNT: 5). The use of ablation was also associated with a reduction in symptomatic atrial arrhythmias (11.8% vs. 26.4%; RR, 0.44; 95% CI, 0.27-0.72; P= 0.001; I2 = 54%) and hospitalization (5.6% vs 18.7%; RR, 0.32; 95% CI, 0.19-0.53; P <0.001) with no significant differences in major adverse events (4.2% vs. 2.8%; RR, 1.52; 95% CI, 0.81-2.85; P=0.19). CONCLUSION: In patients with paroxysmal AF, an early cardiac rhythm control with ablation is associated with a higher probability of survival, fewer repeat procedures, fewer hospitalizations, and probably a decrease in progression to persistent AF.

High resistance of atrioventricular node to cryoablation: a great safety margin targeting perinodal arrhythmic substrates.

BACKGROUND: Findings from animal studies and small series of patients support the greater safety of cryoenergy over radiofrequency in the ablation of arrhythmic substrates near the AV node. OBJECTIVES: The purpose of this study was to systematically evaluate the electrophysiologic effects of successive cryoenergy applications to the human AV node in order to better define the safety margin of cryothermal ablation. METHODS: In 15 patients referred for AV nodal ablation, 94 cryomapping and 105 cryoablation applications were delivered through a 6-mm-tip cryothermal ablation catheter (Freezor Xtra, CryoCath) at predefined sites of the triangle of Koch. RESULTS: Temporary effects on AV conduction were observed in 18 (19%) cryomapping and 38 (36%) cryoablation applications. Persistent effects were observed in 9 (9%) cryoablation applications. Persistent effects were associated with cryoablation at the superior third of the triangle of Koch (P = .05), nadir tip temperature < or = -79 degrees C (P = .007), and effect onset time < or =15 seconds (P = .03). Temperature and effect onset time remained statistically significant after multivariate adjustment (P = .01 and .02, respectively). Overall, persistent complete AV block was achieved with cryoenergy in only one patient. In two additional patients, AV conduction remained modified. In the remaining patients, persistent complete AV block was achieved with radiofrequency (median one application per patient). CONCLUSION: The low rate of persistent AV conduction impairment observed with attempts to cryoablate the AV node supports a great safety margin of perinodal cryothermal ablation.

Enfoque en el diagnóstico diferencial de las taquicardias paroxísticas supraventriculares en el Laboratorio de electrofisiología / Differential diagnosis of paroxysmal supraventricular tachycardia at the electrophysiology laboratory

Resumen: Las taquicardias paroxísticas supraventriculares son arritmias frecuentes y producen importante morbilidad. El estudio electrofisiológico permite hacer el diagnóstico su mecanismo para luego realizar la ablación. El diagnóstico no siempre es sencillo y se debe recurrir a múltiples observaciones y maniobras para alcanzarlo. En la siguiente revisión se discuten los principales criterios usados para el diagnóstico del mecanismo de estas taquicardias durante un estudio electrofisiológico.

Abstract: Paroxysmal supraventricular tachycardias are frequently observed arrhythmias associated to significant morbidity. Electrophysiological study allows the diagnosis of the mechanisms underlying the arrhythmia leading toblation. The diagnosis is not always easy and multiple observations and maneuvers are required to uncover it. In the following review, the main criteria used to diagnose the mechanisms of these tachycardias during an electrophysiological study are discussed.

Taquicardia ventricular por reentrada rama - rama en pacientes con enfermedad de Steinert: serie de tres casos y revisión de la literatura / Bundle branch reentrant ventricular tachycardia in patients with Steinert´s disease: report of three cases and review of the literature

Resumen: Se presentan tres casos clínicos de pacientes con en Enfermedad de Steinert y Taquicardia ventricular recurrente asociada. En los 3 casos el diagnóstico involucró un exhaustivo estudio electrofisiológico que demostró que se trataban de TV rama a rama. Se describen los mecanismos y las maniobras electrofisiológicas para establecer el diagnóstico, como también el tratamiento. Incluye una extensa revisión bibliográfica.

Abstract This is a report of three patients with Steinert´s disease who presented with ventricular tachycardia requiring electrical cardioversion. Extensive electrophysiologic study demonstrated an underlying bundle branch ventricular tachycardia. The mechanisms and the electrophysiological approach to diagnosis are described in detail and the treatment selected is discussed. An extensive review of the literature is included.

Crioablación en taquicardia ortodrómica por vía accesoria oculta parahisiana: caso clínico y revisión de la literatura / Crioablation of orthodromic supraventricular tachycardia win an occult accessory pathway

Abstract An 18-year-old woman with recurrent tachycardia was shown to have orthodromic supraventricular tachycardia through an antero-septal occult pathway near the His. Cryoablation was selected to avoid A-V block. The accesory pathway was finally interrupted after 360 sec of cryoablation. No recurrence was documented after a 12 month follow-up

[Differentiating between atrial flutter and atrial fibrillation using right atrial bipolar endocardial signals]. / Diferenciación entre aleteo y fibrilación auricular en los electrogramas bipolares de aurícula derecha.

INTRODUCTION AND OBJECTIVES: Contemporary atrial pacemakers incorporate pacing modes for treating atrial arrhythmias. Because atrial fibrillation in the right atrium can exhibit an organized pattern, it can be difficult to differentiate from atrial flutter. We assessed criteria for discriminating between atrial flutter and organized atrial fibrillation when using a bipolar electrode in the right atrium. METHODS: Simultaneous bipolar electrograms of the right and left atria were obtained in 45 patients: Group I comprised 15 patients with atypical flutter, Group II comprised 15 with typical flutter, and Group III, 15 with organized atrial fibrillation in the right atrium. The mean cycle length and the mean variation in cycle length observed over 15 seconds in electrograms of the right atrium were recorded. RESULTS: The mean cycle length was longer in Groups I and II than in Group III (232 [21] ms and 234 [24] ms, respectively, versus 183 [16] ms; P< .001). The mean variation in cycle length was less in Groups I and II than in Group III (16 [7] ms and 13 [4] ms, respectively, versus 22 [7] ms; P< .01). A cycle length > or =203 ms discriminated atrial flutter from atrial fibrillation with a sensitivity of 97% and a specificity of 87%. A cycle length variation < or =18 ms discriminated atrial flutter from atrial fibrillation with a sensitivity of 70% and a specificity of 80%. CONCLUSIONS: Cycle length was better than the variation in cycle length for differentiating atrial flutter from organized atrial fibrillation.

[Chest pain unit: first experience in Chile]. / Unidad de dolor torácico: primera experiencia en Chile.

BACKGROUND: In large series, nearly 60% of admissions for suspected acute coronary syndrome (ACS) had a non-coronary etiology of the pain. However, short term mortality of non recognized ACS patients, mistakenly discharged from the emergency room is at least twice greater than the expected if they would had been admitted. The concept of a chest pain unit (CPU) is a methodological approach developed to address these issues. AIM: To evaluate the efficacy of a CPU in the emergency room of a general hospital for evaluation of acute chest pain. MATERIAL AND METHODS: Prospective study of patients with chest pain admitted in the CPU. After a clinical, electrocardiographic and laboratory evaluation with cardiac injury serum markers, patients were stratified in three risk groups, based on the likelihood of ACS of the American Heart Association. High probability patients were admitted to the Coronary Unit (CU) for treatment. Moderate probability patients remained in the CPU for further evaluation and low probability patients were discharged with telephonic follow-up. RESULTS: Of 407 patients, 35, 30 and 35% were stratified as high, intermediate and low probability ACS, respectively. Among patients admitted with high probability, 73% had a confirmed ACS diagnosis. Among intermediate probability patients, 86% were discharged after an evaluation in the CPU without adverse events in the follow-up. CONCLUSION: Structured risk evaluation approach in a CPU improves the management of acute chest pain, identifying high probability patients for fast admission and start of treatment in a CU and allowing safe discharge of low probability ones.

[Aerosolized iloprost combined with a phosphodiesterase inhibitor in the treatment of primary pulmonary hypertension]. / Tratamiento crónico combinado con iloprost y sildenafil en un paciente con hipertensión pulmonar primaria.

Iloprost, a prostacyclin analogue administered by inhalation, improves hemodynamic and functional class variables in patients with primary pulmonary hypertension. However, repetitive inhalations are required due to its short term effects. One potential approach to prolong and increase the effects of aerosolized iloprost might be to combine its use with phosphodiesterase inhibitors. We report a 36 year old female patient with primary pulmonary hypertension treated with this combination. After 18 months of therapy the patient had an improvement in functional class and in the 6 min walk distance despite persistence of high pulmonary pressures. Our case is in agreement with the reported beneficial effect of the association of sildenafil and iloprost. We postulate that functional improvement in primary pulmonary hypertension is not always related to a decrease in pulmonary artery pressure.

[Paroxysmal tachycardia in a patient with a permanent form of junctional reciprocating tachycardia. A case report]. / Taquicardia recíproca de la unión auriculoventricular: características electrofisiológicas en un paciente con la variedad paroxística. Caso clínico.

Junctional reciprocating tachycardia is an atrioventricular reentrant tachycardia whose anterograde conduction occurs via the His Purkinje and the retrograde conduction via an accessory pathway with slow conduction. The most common form is incessant tachycardia but a paroxysmal form also exists. We report a 35 years old female with recurrent paroxysmal tachycardia, that underwent electrophysiological evaluation. A left posterolateral accessory pathway was documented. Reciprocating paroxysmal tachycardia was induced by electrical stimulation and a successful pathway ablation was performed.

[Prognostic value of hyperuricemia in chronic heart failure]. / Valor pronóstico de la hiperuricemia en la insuficiencia cardiaca crónica.

BACKGROUND: Hyperuricemia has been proposed as a risk marker in chronic heart failure, but its value as an independent prognostic is not well established. AIM: To determine the prognostic value of hyperuricemia, in patients with chronic stable heart failure. PATIENTS AND METHODS: Forty six male patients with chronic heart failure, aged 62 +/- 13 years, were studied. Their election fraction was less than 40% and their serum creatinine was less than 2 mg/dl. Serum uric acid and catecholamines, maximal oxygen consumption (VO2 max) and left ventricular ejection fraction were measured. Mortality and the need for cardiac transplant were recorded as endpoints during a mean follow up of 39 +/- 18 months. The relationship between basal measures and the occurrence of events was analyzed using univariate and multivariate methods. RESULTS: Basal VO2 max and left ventricular ejection fraction were 16 +/- 4.6 ml/kg/min and 22 +/- 7% respectively. Eighteen patients died and three required transplantation during the follow up. Patients reaching these endpoints had a lower VO2 max and left ventricular ejection fraction and higher uric acid levels. Multivariate analysis accepted left ventricular ejection fraction (relative risk 0.89, 95% CI 0.82-0.97) and serum uric acid (relative risk 1.335 95% CI 1.02-1.74) as significant predictors of events. The relative risk for cardiac transplantation was 7.07 times higher among those with a serum uric acid over 7 mg/dl. CONCLUSIONS: A high serum uric acid is an independent predictor of bad prognosis in patients with stable chronic heart failure.

Unidad de dolor torácico: primera experiencia en Chile / Chest pain unit: first experience in Chile

Background: In large series, nearly 60 percent of admissions for suspected acute coronary syndrome (ACS) had a non-coronary etiology of the pain. However, short term mortality of non recognized ACS patients, mistakenly discharged from the emergency room is at least twice greater than the expected if they would had been admitted. The concept of a chest pain unit (CPU) is a methodological approach developed to address these issues. Aim: To evaluate the efficacy of a CPU in the emergency room of a general hospital for evaluation of acute chest pain. Material and Methods: Prospective study of patients with chest pain admitted in the CPU. After a clinical, electrocardiographic and laboratory evaluation with cardiac injury serum markers, patients were stratified in three risk groups, based on the likelihood of ACS of the American Heart Association. High probability patients were admitted to the Coronary Unit (CU) for treatment. Moderate probability patients remained in the CPU for further evaluation and low probability patients were discharged with telephonic follow-up. Results: Of 407 patients, 35, 30 and 35 percent were stratified as high, intermediate and low probability ACS, respectively. Among patients admitted with high probability, 73 percent had a confirmed ACS diagnosis. Among intermediate probability patients, 86 percent were discharged after an evaluation in the CPU without adverse events in the follow-up. Conclusion: Structured risk evaluation approach in a CPU improves the management of acute chest pain, identifying high probability patients for fast admission and start of treatment in a CU and allowing safe discharge of low probability ones.