The First Brazilian Cardiovascular Registry of Atrial Fibrillation: Primary Results of the RECALL Study.

Background: It is estimated that atrial fibrillation (AF) affects approximately 1.5 million people in Brazil; however, epidemiological data are limited. We sought to evaluate the characteristics, treatment patterns, and clinical outcomes in patients with AF in Brazil by creating the first nationwide prospective registry.

Growth/differentiation factor-15 (GDF-15) as a predictor of serious arrhythmic events in patients with nonischemic dilated cardiomyopathy.

Introduction: Cardiac biomarkers have been proposed as a new tool to improve risk stratification of serious arrhythmic events in patients with heart failure (HF) beyond estimates of left ventricular ejection fraction. Growth differentiation factor (GDF)-15, a stress-induced cytokine, has been found to correlate with markers of myocardial fibrosis and adverse clinical outcomes, but its role as a predictor of arrhythmic events in patients with nonischemic HF is uncertain.

Methods And Results: A prospective observational study was conducted in 148 nonischemic patients with HF who underwent comprehensive clinical and laboratory evaluation, including measurement of serum GDF-15.

Predictors of Total Mortality and Serious Arrhythmic Events in Non-Ischemic Heart Failure Patients: The Role of Galectin-3.

Background: Risk stratification remains clinically challenging in patients with heart failure (HF) of non-ischemic etiology. Galectin-3 is a serum marker of fibrosis that might help in prognostication.

Objective: To determine the role of galectin-3 as a predictor of major arrhythmic events and overall mortality.

Cardiac Arrhythmias in Patients with COVID-19.

Background: The coronavirus disease 2019 (COVID-19) is associated with cardiovascular clinical manifestations, including cardiac arrhythmias.

Objective: To assess the incidence of cardiac arrhythmias (atrial tachyarrhythmia, bradyarrhythmia, and sustained ventricular tachycardia) and cardiac arrest (CA) in a cohort of patients hospitalized with COVID-19 in a tertiary university-affiliated hospital.

Methods: Cohort study with retrospective analysis of electronic medical records.

GDF-15 as a Biomarker in Cardiovascular Disease.

In the last years, several diagnostic and prognostic biomarkers have been studied in cardiovascular disease. Growth differentiation factor-15 (GDF-15), a cytokine belonging to the transforming growth factor- (TGF-) family, is highly up-regulated in stress and inflammatory conditions and has been correlated to myocardial injury and pressure cardiac overload in animal models. This new biomarker has been positively correlated with increased risk of cardiovascular events in population studies and shown an independent predictor of mortality in patients with coronary artery disease and heart failure.

Worldwide Survey of COVID-19-Associated Arrhythmias.

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Safety and Results of Bioelectrical Impedance Analysis in Patients with Cardiac Implantable Electronic Devices.

Objective: To analyze the dual interference between cardiac implantable electronic devices (CIEDs) and bioelectrical impedance analysis (BIA).

Methods: Forty-three individuals admitted for CIEDs implantation were submitted to a tetrapolar BIA with an alternating current at 800 microA and 50 kHz frequency before and after the devices' implantation. During BIA assessment, continuous telemetry was maintained between the device programmer and the CIEDs in order to look for evidence of possible electric interference in the intracavitary signal of the device.

Direct-Acting Oral Anticoagulants in Atrial Fibrillation: What's New in the Literature.

Atrial fibrillation (AF) is considered the most common sustained cardiac arrhythmia, and it is associated with a significant risk of adverse events, especially ischemic stroke. Oral anticoagulation is the cornerstone for stroke prevention in AF; for many years, only vitamin K antagonists were used for this purpose, with an absolute risk reduction >60%. However, these agents have limitations, such as narrow therapeutic margins and drug-food and drug-drug interactions.

ST elevation myocardial infarction during head-up tilt testing.

We report a case of ST elevation myocardial infarction (STEMI) during head-up tilt testing (HUTT). A 54-year-old man was admitted to our emergency department after four episodes of syncope. Treadmill test and electrophysiological study were normal.

The Profile of the Brazilian Cardiologist - A Sample of Members of the Brazilian Society of Cardiology.

Background: Data from the international literature have shown changes in the profile of cardiologists and in their medical practices. However, there is no data on this in Brazilian cardiologists.

Objective: To evaluate professional and personal characteristics of a sample of Brazilian cardiologists.

Cardiopulmonary exercise testing may not predict appropriate implantable cardioverter defibrillator therapies in heart failure patients.

The prognostic value of cardiopulmonary exercise testing (CPET) variables for major cardiovascular events in patients with heart failure (HF) is widely established. However, the prognostic value of these variables as predictors of appropriate implantable cardioverter-defibrillator (ICD) therapies has not been sufficiently well addressed. This study aimed to evaluate CPET variables such as peak oxygen uptake (VO peak), relationship between change in minute ventilation (VE) and carbon dioxide output (VCO) during incremental exercise (VE/VCO slope) and exercise-related periodic breathing (EPB) as appropriate ICD therapy predictors in HF patients.

Development of ventricular fibrillation after implantation of a biventricular implantable cardioverter defibrillator: what is the mechanism?

Syncopal spells in heart failure patient with cardiovascular implantable electronic devices (CIED) require multiple assessments. T-wave oversensing is a well-described phenomenon that remains significant in modern implantable cardioverter defibrillators (ICD) systems. It can lead to inappropriate therapies and loss of biventricular pacing in those with cardiac resynchronization devices.

Predictors of serious arrhythmic events in patients with nonischemic heart failure.

Purpose: Risk stratification of serious arrhythmic events in patients with nonischemic heart failure (HF), beyond estimates of left ventricular ejection fraction (LVEF), remains an important clinical challenge. This study aims to determine the clinical value of different noninvasive and invasive tests as predictors of serious arrhythmic events in patients with nonischemic HF.

Methods: A prospective observational study was conducted including 106 nonischemic HF patients who underwent a comprehensive clinical and laboratory evaluation including two-dimensional echocardiography, 24-h Holter monitoring, cardiopulmonary exercise testing (CPX), and an invasive electrophysiological study.

Short-term Effects of High-Dose Caffeine on Cardiac Arrhythmias in Patients With Heart Failure: A Randomized Clinical Trial.

Importance: The presumed proarrhythmic action of caffeine is controversial. Few studies have assessed the effect of high doses of caffeine in patients with heart failure due to left ventricular systolic dysfunction at high risk for ventricular arrhythmias.

Objective: To compare the effect of high-dose caffeine or placebo on the frequency of supraventricular and ventricular arrhythmias, both at rest and during a symptom-limited exercise test.

Sudden cardiac death markers in non-ischemic cardiomyopathy.

Heart failure is an increasingly prevalent disease associated with high morbidity and mortality. In 30-40% of patients, the etiology is non-ischemic. In this group of patients, the implantable cardioverter-defibrillator (ICD) prevents sudden death and decreases total mortality.

Effect of caffeine on ventricular arrhythmia: a systematic review and meta-analysis of experimental and clinical studies.

Aims: The relationship between caffeine consumption and the occurrence of arrhythmias remains controversial. Despite this lack of scientific evidence, counselling to reduce caffeine consumption is still widely advised in clinical practice. We conducted a systematical review and meta-analysis of interventional studies of the caffeine effects on ventricular arrhythmias.

Stratification of the risk of sudden death in nonischemic heart failure.

Despite significant therapeutic advancements, heart failure remains a highly prevalent clinical condition associated with significant morbidity and mortality. In 30%-40% patients, the etiology of heart failure is nonischemic. The implantable cardioverter-defibrillator (ICD) is capable of preventing sudden death and decreasing total mortality in patients with nonischemic heart failure.

Sudden cardiac death in Brazil: study based on physicians' perceptions of the public health care system.

Background: There are no available statistical data about sudden cardiac death in Brazil. Therefore, this study has been conducted to evaluate the incidence of sudden cardiac death in our population and its implications.

Methods: The research methodology was based on Thurstone's Law of Comparative Judgment, whose premise is that the more an A stimulus differs from a B stimulus, the greater will be the number of people who will perceive this difference.