The effect of age and sex on the diagnostic yield of the echocardiogram in patients with syncope. / Efecto de la edad y el sexo en el rendimiento diagnóstico del ecocardiograma en pacientes con síncope.

INTRODUCTION: Syncope is the motivation for numerous diagnostic tests, among them transthoracic echocardiography (TTE); however, previous evidence suggests there is little utility in this test. Our objective was to assess its diagnostic yield in syncope, analysing the effect of age and sex. MATERIAL AND METHODS: We conducted an observational study that included patients with syncope and who underwent TTE between 1990-2015. We defined diagnostic findings related to syncope and performed a descriptive analysis, assessing the diagnostic yield (overall and according to age and sex). RESULTS: The study included 3,302 patients and measured a diagnostic yield of 8.8%; the most common finding was ventricular dysfunction (4.5%). The probability of a diagnostic TTE significantly increased with age (p<.001) but was low for patients younger than 50 years (2.3%). The male sex was significantly related with a diagnostic TTE (p<.001), mostly due to the higher rate of ventricular dysfunction. CONCLUSIONS: The diagnostic yield of TTE in patients with syncope is moderate, low in patients younger than 50 years and lower in women than in men. These factors should be considered when conducting a diagnostic study of patients with syncope.

Pathophysiology of neurally-mediated syncope. / Fisiopatología del síncope neuralmente mediado.

INTRODUCTION: Neurally-mediated syncope (NMS) is defined as a transient loss of consciousness due to an abrupt and intermittent drop in blood pressure (BP). OBJECTIVES: This study describes the putative pathophysiological mechanisms giving rise to NMS, the role of baroreflex (BR), and the interaction of its main haemodynamic variables: heart rate (HR) and BP. DEVELOPMENT: Episodic dysregulation affects control over the haemodynamic variables (HR and BP) mediated by baroreflex mechanisms. During active standing, individuals experience a profound transient drop in systolic BP due to the effect of gravity on the column of blood and probably also because of reflex vasodilation. Abnormalities in the BR in NMS could be due to a more profound drop in BP upon standing, or to delayed or incomplete vasoconstriction resulting from inhibited or delayed sympathetic activity. CONCLUSIONS: Sympathetic hyperactivity is present in patients with NMS at rest and before syncope. During active standing or passive tilting, excessive tachycardia may be followed by bradycardia and profound hypotension. Recovery of systolic BP is delayed or incomplete.

Glossopharyngeal neuralgia with cardioinhibitory syncope: Is a permanent pacemaker required?

Glossopharyngeal neuralgia is a rare facial pain syndrome, which in more rare cases can be associated with syncope. We present the outcome of a case report that combines this rare association that received medical therapy with anti-epileptic medication and permanent dual chamber pacemaker implantation. In this case, syncope episodes were associated with both vasodepressor and cardioinhibitory reflex syncope types. The patient found relief from syncope, hypotension, and pain after initiation of anti-epileptic therapy. Although a dual chamber pacemaker was implanted, the pacemaker interrogation revealed no requirement for pacing at one-year follow-up. As far as we know, this is the first case that reports pacemaker interrogation during follow-up and, taking into account the absence of pacemaker activation at one-year follow-up, the device was not needed to prevent bradycardia and syncope episodes. This case report supports the current guidelines for pacing in neurocardiogenic syncope, by demonstrating a lack of requirement for pacing in the event of both cardioinhibitory and vasodepressor responses.

Cardioneuroablation for severe neurocardiogenic syncope.

INTRODUCTION AND OBJECTIVES: Cardioneuroablation (CNA), a technique based on radiofrequency ablation of cardiac vagal ganglia, was developed to treat recurrent vasovagal syncope (VVS) with a predominant cardioinhibitory component, as an alternative to pacemaker implantation. The aim of our study was to evaluate the safety and success rate of CNA guided by extracardiac vagal stimulation in patients with highly symptomatic cardioinhibitory VVS. METHODS: Prospective study of patients who underwent anatomically guided CNA at two cardiology centers. All patients had a history of recurrent syncope with a predominant cardioinhibitory component and refractory to conventional measures. Acute success was determined by the absence or significant reduction of cardiac parasympathetic response to extracardiac vagal stimulation. The primary endpoint was the recurrence of syncope during follow-up. RESULTS: In total, 19 patients (13 males; mean age 37.8±12.9 years) were included. Ablation was acutely successful in all patients. One patient had a convulsive episode after the procedure, which was deemed unrelated to the ablation, requiring admission to intensive care but without sequelae. No other complications occurred. At a mean follow-up of 21.0±13.2 months (range 3-42 months), 17 patients remained free of syncope. The remaining two patients had recurrence of syncope and, despite undergoing a new ablation procedure, required pacemaker implantation during follow-up. CONCLUSION: Cardioneuroablation, confirmed by extracardiac vagal stimulation, appears to be an effective and safe treatment option for highly symptomatic patients with refractory VVS with a predominant cardioinhibitory component, providing a new potential approach as an alternative to pacemaker implantation.

Vasovagal syncope: An overview of pathophysiological mechanisms.

Syncope is a short-term transient loss of consciousness, characterized by rapid onset and complete spontaneous recovery. According to the 2018 European Society of Cardiology guidelines, three different types of syncope have been identified. However, all forms of syncope share a common final pathophysiological event, global cerebral hypoperfusion, which results from the inability of the circulatory system to maintain blood pressure at the level required to efficiently supply blood to the brain. The vasovagal syncope (VVS) is the most common form of syncope. Although, VVS is generally harmless, its frequent occurrence can negatively affect quality of life and increase the risk of adverse events. The pathophysiological mechanisms underlying VVS remain obscure. The multifaceted nature of VVS presents a veritable challenge to understanding this condition and developing preventative strategies. Thus, the aim of this review was to discuss the factors contributing to the pathogenesis of VVS and provide guidance for future research.

Arrhythmic risk in single or recurrent episodes of unexplained syncope with complete bundle branch block.

INTRODUCTION AND OBJECTIVES: Patients with a single syncopal episode (SSE) and complete bundle branch block (cBBB) are frequently managed more conservatively than patients with recurrent episodes (RSE). The objective of this study was to analyze if there are differences between patients with single or recurrent unexplained syncope and cBBB in arrhythmic risk, the diagnostic yield of tests, and clinical outcomes. METHODS: Cohort study of consecutive patients with unexplained syncope and cBBB with a median follow-up time of 3 years. The patients were evaluated via a stepwise workup protocol based on electrophysiological study (EPS) and long-term follow-up with an implantable cardiac monitor. RESULTS: Of the 503 patients included in the study, 238 (47.3%) had had only 1 syncopal episode. The risk of an arrhythmic syncope was similar in both groups (58.8% in SSE vs 57.0% in RSE; P=.68), also after adjustment for possible confounding variables (HR, 1.06; 95%CI, 0.81-1.38; P=.674). No significant differences between the groups were found in the EPS results and implantable cardiac monitor diagnostic yield. A total of 141 (59.2%) patients with SSE and 154 (58.1%) patients with RSE required cardiac device implantation (P=.797). After appropriate treatment, 35 (7%) patients had recurrence of syncope. The recurrence rate and mortality were also similar in both groups. CONCLUSIONS: Patients with cBBB and unexplained syncope are at high risk of an arrhythmic etiology, even after the first syncopal episode. Patients with SSE and RSE have a similar arrhythmic risk and similar outcomes, and therefore there is no clinical justification for not managing them in the same manner.

Syncope in the athlete - Minor changes, major diagnosis!

We report the case of a 17-year-old athlete who resorted to the emergency department for palpitations and dizziness while exercising. He mentioned two exercise-associated episodes of syncope in the last six months. He was tachycardic and hypotensive. The electrocardiogram showed regular wide complex tachycardia, left bundle branch block morphology with superior axis restored to sinus rhythm after electrical cardioversion. In sinus rhythm, it showed T-wave inversion in V1-V5. Transthoracic echocardiography revealed mild dilation and dysfunction of the right ventricle (RV) with global hypocontractility. Cardiac magnetic resonance (CMR) revealed a RV end diastolic volume indexed to body surface area of 180 ml/m2, global hypokinesia and RV dyssynchrony, subepicardial late enhancement in the distal septum and in the middle segment of the inferoseptal wall. The patient underwent a genetic study which showed a mutation in the gene that encodes the desmocolin-2 protein (DSC-2), which is involved in the pathogenesis of arrhythmogenic right ventricular cardiomyopathy (ARVC). According to the modified Task Force Criteria for this diagnosis, the patient presented four major criteria for ARVC. Thus, a subcutaneous cardioverter was implanted, and the patient was followed up at the cardiology department. Arrhythmogenic right ventricular cardiomyopathy diagnosis is based on structural, functional, electrophysiological and genetic criteria reflecting underlying histological changes. This case depicts the essential characteristics for disease recognition.

Practical approach to referral from primary health care to a cardiology hospital consultation in 2022.

In Portugal, up to 38% of the population has cardiovascular disease, which highlights the importance of primary health care (PHC) in its management. Adequate management of people with cardiovascular disease often requires hospital referral for a cardiology consultation. However, it is not always easy to ascertain which situations should be referred, especially given that PHC does not have access to all diagnostic exams recommended by international guidelines, such as natriuretic peptides in heart failure or computed tomography coronary angiogram in chronic coronary syndromes, among others. The aim of this document is to describe a practical approach to the most frequent heart diseases that may require a referral for a hospital cardiology consultation. Thus, in the different chapters, the recommendations for referral are highlighted generically according to group of disease, as well as, albeit briefly, the initial clinical approach within the scope of PHC for a differential diagnosis and more efficient follow-up. A modified Metaplan methodology was used. A panel of 4 cardiology specialists and 3 specialists in General and Family Medicine developed this document, which should not be taken as an official guideline, but as additional guidance for the correct referral of patients. It is therefore advisable to validate these recommendations locally with the referral hospital, as well as to be aware of the respective international and national guidelines.

Long-term recurrences and mortality in patients with noncardiac syncope.

INTRODUCTION AND OBJECTIVES: There are no in-depth studies of the long-term outcome of patients with syncope after exclusion of cardiac etiology. We therefore analyzed the long-term outcome of this population. METHODS: For 147 months, we included all patients with syncope referred to our syncope unit after exclusion of a cardiac cause. RESULTS: We included 589 consecutive patients. There were 313 (53.1%) women, and the median age was 52 [34-66] years. Of these, 405 (68.8%) were diagnosed with vasovagal syncope (VVS), 65 (11%) with orthostatic hypotension syncope (OHS), and 119 (20.2%) with syncope of unknown etiology (SUE). During a median follow-up of 52 [28-89] months, 220 (37.4%) had recurrences (21.7% ≥ 2 recurrences), and 39 died (6.6%). Syncope recurred in 41% of patients with VVS, 35.4% with OHS, and 25.2% with SUE (P=.006). In the Cox multivariate analysis, recurrence was correlated with age (P=.002), female sex (P <.0001), and the number of previous episodes (< 5 vs ≥ 5; P <.0001). Death occurred in 15 (3.5%) patients with VVS, 11 (16.9%) with OHS, and 13 (10.9%) with SUE (P=.001). In the multivariate analysis, death was associated with age (P=.0001), diabetes (P=.007), and diagnosis of OHS (P=.026) and SUE (P=.020). CONCLUSIONS: In patients with noncardiac syncope, the recurrence rate after 52 months of follow-up was 37.4% and mortality was 6.6% per year. Recurrence was higher in patients with a neuromedial profile and mortality was higher in patients with a nonneuromedial profile.

The effect of age and sex on the diagnostic yield of the echocardiogram in patients with syncope.

INTRODUCTION: Syncope is the motivation for numerous diagnostic tests, among them transthoracic echocardiography (TTE); however, previous evidence suggests there is little utility in this test. Our objective was to assess its diagnostic yield in syncope, analysing the effect of age and sex. MATERIAL AND METHODS: We conducted an observational study that included patients with syncope and who underwent TTE between 1990 and 2015. We defined diagnostic findings related to syncope and performed a descriptive analysis, assessing the diagnostic yield (overall and according to age and sex). RESULTS: The study included 3302 patients and measured a diagnostic yield of 8.8%; the most common finding was ventricular dysfunction (4.5%). The probability of a diagnostic TTE significantly increased with age (p<.001) but was low for patients younger than 50 years (2.3%). The male sex was significantly related with a diagnostic TTE (p<.001), mostly due to the higher rate of ventricular dysfunction. CONCLUSIONS: The diagnostic yield of TTE in patients with syncope is moderate, low in patients younger than 50 years and lower in women than in men. These factors should be considered when conducting a diagnostic study of patients with syncope.

Safety in Dermatologic Procedures: Anaphylaxis, Vasovagal Reaction, and Hyperventilation. / Seguridad en procedimientos dermatológicos: anafilaxia, reacción vasovagal e hiperventilación.

This article, part of a the series on safety in dermatologic procedures, covers the diagnosis, prevention, management, and treatment of 3 situations or conditions. The first condition we address is anaphylaxis, an uncommon but severe and potentially fatal reaction that must be recognized quickly so that urgent management coordinated with an anesthesiologist can commence. The second is the vasovagal reaction, which is the most common complication in dermatologic surgery. This event, which occurs in 1 out of every 160 procedures, usually follows a benign course and resolves on its own. However, in patients susceptible to vasovagal reactions, syncope may lead to asystole and cardiac arrest. The third is acute hyperventilation syndrome, which is an anomalous anxiety-related increase in breathing rate beyond metabolic requirements. Brief practical recommendations for managing all 3 events are included.

Safety in dermatologic procedures: anaphylaxis, vasovagal reaction, and hyperventilation.

This article, part of a the series on safety in dermatologic procedures, covers the diagnosis, prevention, management, and treatment of 3 situations or conditions. The first condition we address is anaphylaxis, an uncommon but severe and potentially fatal reaction that must be recognized quickly so that urgent management coordinated with an anesthesiologist can commence. The second is fainting due to a vasovagal reaction, which is the most common complication in dermatologic surgery. This event, which occurs in 1 out of every 160 procedures, usually follows a benign course and resolves on its own. However, in patients susceptible to vasovagal reactions, syncope may lead to asystole and cardiac arrest. The third is acute hyperventilation syndrome, which is an anomalous anxiety-related increase in breathing rate beyond metabolic requirements. Brief practical recommendations for managing all 3 events are included.

EGSYS score for the prediction of cardiac etiology in syncope: Is it useful in an outpatient setting? / Score EGSYS para predição de etiologia cardíaca na síncope: tem utilidade no contexto de consulta?

INTRODUCTION: The EGSYS score uses clinical variables to predict which patients may have cardiac (CS) or non-cardiac syncope (NCS) and has been validated in the emergency department setting. This study aims to determine whether the score has the same applicability in an outpatient setting. METHODS: In this retrospective study of all patients observed in the outpatient setting of a hospital with a syncope unit between January 2015 and December 2016, the EGSYS score was calculated for each patient, and its sensitivity and specificity were determined for the prediction of CS in patients with score ≥3. RESULTS: A total of 224 patients, mean age 64.3±21.7 years, 116 (51.8%) male, were analyzed. In the 163 (72.7%) patients with confirmed syncope, CS was diagnosed in 27 (16.6%) and NCS in 136 (83.4%). The EGSYS score was ≥3 in 40 (20.0%) patients with NCS and in 13 (48.1%) with CS. A positive score had a sensitivity of 48.2% (95% CI: 28.7-68.1), a specificity of 77.9% (95% CI: 70.0-84.6), and a positive and negative predictive value of 30.2% (95% CI: 20.8-41.8) and 88.3% (95% CI: 83.9-91.7), respectively. CONCLUSION: The EGSYS score has limited usefulness in an outpatient setting, where observed patients have already been been medically assessed. Given its high specificity and negative predictive value, it may be useful to reassure low-risk patients and family members.

Pediatric patients' head-up-tilt-test with pharmacological challenge, it is safe?

Syncope in pediatrics represents an important cause of visits to the emergency units. For this reason, excluding a cardiac or malignant origin is essential at the time of the initial approach to determine what is the next step in management, or if they need to be referred to a pediatric cardiologist and/or electrophysiologist. Vasovagal syncope is the most frequent cause of syncope in pediatrics, in which a detailed clinical history is enough to make the diagnosis. If no diagnosis is concluded by the history, or if it is necessary to define the hemodynamic response of the patients, the head-up-tilt-test is indicated; this will trigger syncope due to an orthostatic stress caused by the angulated table (passive phase). If a negative response remains, it can be followed by a pharmacologic challenge to trigger the hemodynamic response, which is still controversial in pediatrics. The pharmacologic challenge increases the sensitivity with a slight reduction in test specificity. Although there is not a specific drug for the challenge in pediatric patients yet, the most commonly drugs used are nitrates and isoproterenol, the latter related to a great number of adverse effects. Sublingual administration of nitrates in the challenge has been proven to be ideal, effective, and safe in this specific age group. The aim of this article is to make a literature search to demonstrate the effectiveness and safety of the pharmacologic challenge during the head-up-tilt-test in pediatrics, emphasizing a study conducted at the National Institute of Cardiology with isosorbide dinitrate.

El síncope en edades pediátricas representa una causa importante en las visitas a unidades de urgencias, por lo que excluir un origen cardíaco o maligno es fundamental al momento del abordaje inicial para determinar la conducta a seguir o la necesidad de derivar al cardiólogo pediatra o electrofisiólogo. El síncope vasovagal (SVV) es la causa más frecuente de síncope en pediatría, para cuyo diagnóstico basta una historia clínica detallada. Cuando ésta no es suficiente para determinar el diagnóstico de síncope reflejo o es necesario definir el tipo de respuesta que lo origina, está indicada una prueba de mesa inclinada que produce un estrés ortostático por la angulación y ello desencadena un síncope (fase pasiva). En pruebas no concluyentes está indicado un reto farmacológico para precipitar la respuesta hemodinámica, pero aún es un tema de controversia en edades pediátricas. El reto farmacológico incrementa la sensibilidad de la prueba, con una ligera reducción de la especificidad. Si bien no existe todavía un medicamento específico para la población pediátrica, los más empleados son los nitratos y el isoproterenol, este último relacionado con un mayor número de efectos adversos. La administración sublingual de los nitratos utilizados ha demostrado ser ideal, efectiva y segura en los pacientes pediátricos. El objetivo del artículo es realizar una revisión de las publicaciones médicas que demuestran la efectividad y seguridad del reto farmacológico durante la prueba de mesa inclinada en pacientes pediátricos, con énfasis en un estudio conducido en el Instituto Nacional de Cardiología con dinitrato de isosorbida (DNIS).

Pediatrics patients head-up tilt test with pharmacological challenge, it is safe?

Syncope in pediatrics represents an important cause of visits to the emergency units. For this reason, excluding a cardiac or malignant origin is essential at the time of the initial approach in order to determine what is the next step in management, or if they need to be referred to a pediatric cardiologist and/or electrophysiologist. Vasovagal syncope is the most frequent cause of syncope in pediatrics, in which a detailed clinical history is enough to make the diagnosis. If no diagnosis is concluded by the history, or if it is necessary to define the hemodynamic response of the patients, the head-up tilt test is indicated; this will trigger syncope due to an orthostatic stress caused by the angulated table (passive phase). If a negative response remains, it can be followed by a pharmacologic challenge in order to trigger the hemodynamic response, which is still controversial in pediatrics. The pharmacologic challenge increases the sensitivity with a slight reduction in test specificity. Although there is not a specific drug for the challenge in pediatric patients yet, the most commonly drugs used are nitrates and isoproterenol, the latter related to a great number of adverse effects. Sublingual administration of nitrates in the challenge has been proven to be ideal, effective and safe in this specific age group. The aim of this article is to make a literature search in order to demonstrate the effectiveness and safety of the pharmacologic challenge during the head-up tilt test in pediatrics, emphasizing a study conducted at the National Institute of Cardiology with isosorbide dinitrate.

El síncope en edades pediátricas representa una causa importante en las visitas a unidades de urgencias, por lo que excluir un origen cardíaco o maligno es fundamental al momento del abordaje inicial para determinar la conducta a seguir o la necesidad de derivar al cardiólogo pediatra o electrofisiólogo. El síncope vasovagal (SVV) es la causa más frecuente de síncope en pediatría, para cuyo diagnóstico basta una historia clínica detallada. Cuando ésta no es suficiente para determinar el diagnóstico de síncope reflejo o es necesario definir el tipo de respuesta que lo origina, está indicada una prueba de mesa inclinada que produce un estrés ortostático por la angulación y ello desencadena un síncope (fase pasiva). En pruebas no concluyentes está indicado un reto farmacológico para precipitar la respuesta hemodinámica, pero aún es un tema de controversia en edades pediátricas. El reto farmacológico incrementa la sensibilidad de la prueba, con una ligera reducción de la especificidad. Si bien no existe todavía un medicamento específico para la población pediátrica, los más empleados son los nitratos y el isoproterenol, este último relacionado con un mayor número de efectos adversos. La administración sublingual de los nitratos utilizados ha demostrado ser ideal, efectiva y segura en los pacientes pediátricos. El objetivo del artículo es realizar una revisión de las publicaciones médicas que demuestran la efectividad y seguridad del reto farmacológico durante la prueba de mesa inclinada en pacientes pediátricos, con énfasis en un estudio conducido en el Instituto Nacional de Cardiología con dinitrato de isosorbida (DNIS).

Atrioventricular block in patients undergoing treatment with bradycardic drugs. Predictors of pacemaker requirement.

INTRODUCTION AND OBJECTIVES: Atrioventricular block (AVB) in the presence of bradycardic drugs (BD) can be reversible, and pacemaker implantation is controversial. Our objective was to analyze the pacemaker implantation rate in the mid-term, after BD suspension, and to identify predictive factors. METHODS: We performed a cohort study that included patients attending the emergency department with high-grade AVB in the context of BD. We studied the persistence of AVB after BD discontinuation, recurrence in patients with AVB resolution, and the predictive variables associated with pacemaker requirement at 3 years. RESULTS: Of 127 patients included (age, 79 [71-83] years), BAV resolved in 60 (47.2%); among these patients, recurrence occurred during the 24-month median follow-up in 40 (66.6%). Pacemaker implantation was required in 107 patients (84.3%), despite BD discontinuation. On multivariable analysis, the variables associated with pacemaker need at 3 years were heart rate <35 bpm (OR, 8.12; 95%CI, 1.82-36.17), symptoms other than syncope (OR, 4.09; 95%CI, 1.18-14.13), and wide QRS (OR, 5.65; 95%CI, 1.77-18.04). Concomitant antiarrhythmic treatment was associated with AVB resolution (OR, 0.12; 95%CI, 0.02-0.66). CONCLUSIONS: More than 80% of patients with AVB secondary to BD require pacemaker implantation despite drug discontinuation. Predictive variables were wide QRS, heart rate <35 bpm, and clinical presentation other than syncope.

Diagnostic and therapeutic approach to cardioinhibitory reflex syncope: A complex and controversial issue. / Abordagem diagnóstica e terapêutica da síncope reflexa cardio­inibitória ­ A complexidade de um tema controverso.

Syncope is defined as a transient loss of consciousness due to global cerebral hypoperfusion and is one of the leading causes of emergency department admission. The initial approach should focus on excluding non-syncopal causes for loss of consciousness and risk stratification for cardiac cause, in order to ensure an appropriate etiological investigation and therapeutic approach. Vasovagal syncope (VVS), the most common type of syncope, should be assumed once other causes are excluded. Pathophysiologically, the vasovagal reflex is the result of a paradoxical autonomic response, leading to hypotension and/or bradycardia. VVS has not been shown to affect mortality, but morbidity may be considerable in those with recurrent syncopal episodes. The management of VVS includes both non-pharmacological and pharmacological measures that act on various levels of the reflex arc that triggers the syncopal episode. However, most are of uncertain benefit given the scarcity of high-quality supporting evidence. Pacemaker therapy may be considered in recurrent refractory cardioinhibitory reflex syncope, for which it is currently considered a robust intervention, as noted in the European guidelines. Non-randomized and unblinded studies have shown a potential benefit of pacing in recurrent VVS, but double-blinded randomized controlled trials have not consistently demonstrated positive results. We performed a comprehensive review of the current literature and recent advances in cardiac pacing and pacing algorithms in VVS, and discuss the diagnostic and therapeutic approach to the complex patient with recurrent VVS and reduced quality of life.

Utilidad de la midodrina para controlar el síncope vasovagal: ¿la recomienda la evidencia? / Usefulness of Midodrine for the Control of Recurrent Vasovagal Syncope: Does the Evidence Recommend it? / Utilidade da midodrina no controle da síncope vasovagal: as evidencias a recomendam?

Introducción:El síncope vasovagal es la principal causa de pérdida transitoria de la conciencia, y es un motivo de consulta cada vez más frecuente en pediatría y medicina del adulto. La midodrina es un agonista de los recepto-res alfa, de acción periférica, empleada principalmente en el manejo de la hipotensión ortostática; sin embargo, también se ha evaluado en el síncope vasovagal, con resultados prometedores.Objetivo:Analizar la evidencia más reciente sobre la utilidad de la midodrina para el control y la prevención del síncope vasovagal.Materiales y métodos: Se realizó una búsqueda bibliográfica utilizando términos de búsqueda como Vasovagal Syncope y Midodrine, así como sinónimos, que se combinaron con operadores booleanos, en cinco bases de datos, hasta octubre del 2022. Se incluyeron estudios originales, revisiones sistemáticas y metanálisis, publicados tanto en inglés como en español.Resultados:Ensayos controlados aleatorizados y revisiones sistemáticas y metanálisis difieren ligeramente entre resultados, pero estos demuestran un efecto global protector. La evidencia más reciente y completa indica que utilizar este agente reduce significativamente la positividad al realizar la prueba de la mesa inclinada y que previene la aparición de episodios sincopales.Conclusiones:Aunque la evidencia actual sobre la eficacia de la midodrina respecto a la prevención y control del síncope vasovagal es limitada, se observa un efecto protector significativo, porque disminuye el riesgo de sufrir un episodio sincopal, aproximadamente hasta en un 50 %.Palabras clave: midodrina; síncope vasovagal; síncope; adrenérgicos; medicina basada en la evidencia

Introduction: Vasovagal syncope is the main cause of transient loss of consciousness, being an in-creasingly frequent reason for consultation in pediatrics and adult medicine. Midodrine, a periphe-rally acting alpha-receptor agonist, is mainly used in the management of orthostatic hypotension. However, it has also been evaluated in vasovagal syncope, with promising results. Objective: To analyze the most recent evidence on the usefulness of midodrine for the control and prevention of vasovagal syncope. Materials and Methods: A literature search was performed using search terms such as "Vasovagal Syncope" and "Midodrine," as well as synonyms, which were combined with Boolean operators, in 5 databases until October 2022. Original studies, systematic reviews and meta-analyses, published in both English and Spanish, were included. Results: Randomized controlled trials and systematic reviews and meta-analyses differ slightly between results, but these demonstrate an overall protective effect. The most recent and complete evidence shows that using this agent significantly reduces the probability of positivity when performing the tilt table test and prevents the occurrence of syncopal episodes. Conclusions: Although current evidence on the efficacy of midodrine with respect to the prevention and control of vasovagal syncope is limited, a significant protective effect is observed, reducing the risk of suffering syncopal episode by approximately up to 50%

Introdução: a síncope vasovagal é a principal causa de perda transitória de consciência e é um motivo cada vez mais comum de consulta em pediatria e medicina de adultos. A midodrina é um agonista do receptor alfa de ação periférica usado principalmente no tratamento da hipotensão ortostática; no entanto, ela também foi avaliada na síncope vasovagal, com resultados promissores. Objetivo: Revisar as evidências mais recentes sobre a utilidade da midodrina para o controle e a pre-venção da síncope vasovagal. Materiais e métodos: Foi realizada uma pesquisa na literatura usando termos de pesquisa como Va-sovagal, Syncope e Medodrine, bem como sinônimos, que foram combinados com operadores boo-leanos, em cinco bancos de dados, até outubro de 2022. Foram incluídos estudos originais, revisões sistemáticas e metanálises, publicados em inglês e espanhol. Resultados: Os ensaios clínicos randomizados, as revisões sistemáticas e as metanálises diferem ligei-ramente entre os resultados, mas demonstram um efeito protetor geral. As evidências mais recentes e abrangentes indicam que o uso desse agente reduz significativamente a positividade no teste de inclinação da mesa e evita a ocorrência de episódios de síncope. Conclusões: Embora as evidências atuais sobre a eficácia da midodrina em relação à prevenção e ao controle da síncope vasovagal sejam limitadas, observa-se um efeito protetor significativo, pois ela diminui o risco de sofrer um episódio sincopal em aproximadamente 50%

Fibrilación auricular de novo y miocarditis aguda / De novo atrial fibrillation and acute myocarditis

Introducción: la miocarditis (MCT) se define como un infiltrado inflamatorio del miocardio con degeneración y/o necrosis asociada. Su etiología incluye múltiples gérmenes, tóxicos y enfermedades autoinmunes entre otros. La causa más común es la viral y el diagnóstico es un reto por la variabilidad de manifestaciones, imágenes y rendimiento del laboratorio. Objetivo:describir dos casos de miocarditis que debutaron con fibrilación auricular como manifestación poco usual. Metodología: se registraron dos casos en Cali, Colombia, con diagnóstico de miocarditis por resonancia magnética cardíaca (cRNM) contrastada. Presentación de los casos: el primero corresponde a una mujer de 66 años con antecedentes de diabetes e hipotiroidismo que ingresó por síncope y el segundo a un paciente joven con dolor torácico de 43 años sin antecedentes patológicos. Se documentó fibrilación auricular (FA) y MCT aguda por hallazgos en la cRNM. Se dió manejo médico y los pacientes evolucionaron en forma satisfactoria sin falla cardíaca en el seguimiento. Discusión y conclusiones: los casos ponen en evidencia la heterogeneidad de las manifestaciones clínicas de la MCT aguda y la importancia de sospecharla ante FA de novo. El diagnóstico puede retrasarse en nuestro medio por la falta de acceso a la cRNM, que se ha constituido como una herramienta fundamental para diferenciarla de otras etiologías que también elevan marcadores como la troponina ultrasensible y ponen en riesgo la vida del paciente como la isquemia miocárdica.

Introduction: myocarditis (MCT) is characterized by an inflammatory infiltration into the myocardium associated with degeneration and/or necrosis. Its etiologies include multiple bacteria, toxins, and autoimmune diseases among others. But most commonly it is induced by viruses. Diagnosis is challenging due to its variable presentation, imaging, and laboratory results. Objective: to describe two cases of myocarditis which debuted with atrial fibrillation as an unusual manifestation. Methodology: two cases were registered in Cali, Colombia, with myocarditis diagnosed by contrasted cardiovascular magnetic resonance imaging (cMRI). Cases: the first case corresponds to a 66-year-old female patient with a history of diabetes and hypothyroidism who was admitted for a syncope episode. The second case is a 43-year-old male with chest pain and a negative medical history. Atrial fibrillation (AF) and acute MCT were documented by cMRI. Patients received medical treatment and evolved satisfactorily presenting no cardiac failure at follow-up. Discussion and conclusions: these cases show the heterogeneity of acute MCT clinical manifestations and the importance of suspecting MCT in the presence of de novo AF. Diagnosis may be delayed in our setting due to the lack of access to cMRI, which has become a fundamental tool to distinguish MCT from other life-threatening conditions, such as myocardial ischemia, which also elevate markers such as ultrasensitive troponin

[Determination of prognostic value of the OESIL risk score at 6 months in a Colombian cohort with syncope evaluated in the emergency department; first Latin American experience]. / Determinación del valor pronóstico a 6 meses del puntaje de riesgo OESIL en una cohorte colombiana con síncope evaluada en el servicio de urgencias, primera experiencia latinoamericana.

OBJECTIVES: To establish the prognostic value, with sensitivity, specificity, positive predictive value, and negative predictive value for the OESIL syncope risk score to predict the presentation of severe outcomes (death, invasive interventions, and readmission) after 6 months of observation in adults who consulted the emergency department due to syncope. METHODS: Observational, prospective, and multicentre study with enrolment of subjects older than 18 years, who consulted in the emergency department due to syncope. A record was mad of the demographic and clinical information of all patients. The OESIL risk score was calculated, and severe patient outcomes were followed up during a 6 month period using telephone contact. RESULTS: A total of 161 patients met the inclusion criteria and were followed up for 6 months. A score above or equal to 2 in the risk score, classified as high risk, was present in 72% of the patients. The characteristics of the risk score to predict the combined outcome of mortality, invasive interventions, and readmission for a score above or equal to 2 were 75.7, 30.5, 43.1, and 64.4% for sensitivity, specificity, positive predictive value, and negative predictive value, respectively. CONCLUSIONS: A score above or equal to 2 in the OESIL risk score applied in Colombian population was of limited use to predict the studied severe outcomes. This score will be unable to discriminate between patients that benefit of early admission and further clinical studies.