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. The study endpoints were serious arrhythmic events (which included appropriate implantable cardioverter-defibrillator therapy and sudden cardiac death) and all-cause mortality. Mean age of the cohort was 54.8±12.7 years, and mean left ventricular ejection fraction (LVEF) was 27.4±7.5. During a mean follow-up time of 42 months, arrhythmic events occurred in 28 patients (19%), and 40 patients (27%) died. An increase in serum GDF-15 (log-transformed) correlated linearly with a higher risk of serious arrhythmic events (HR 1.14, 95% CI 1.01-1.28, p=0.03) even after adjustment for other potential clinical predictors (HR 1.16, 95% CI 1.02-1.32, p=0.02). GDF-15 was also strongly and independently associated with all-cause mortality (HR 1.17, 1.05-1.31, p=0.004). Conclusion: In this cohort of nonischemic HF patients on optimized medical treatment, serum GDF-15 levels were independently associated with major arrhythmic events and overall mortality. This biomarker may add prognostic information beyond LVEF to better stratify the risk of sudden death in this particular population.

Advances in human reproductive science are allowing women to get pregnant even at advanced ages. Thus, the incidence of arrhythmic events in pregnancy is rising and represents a significant cause of hospitalization and morbidity for mother and fetus. The most common arrhythmias in this context are atrial fibrillation and supraventricular tachycardia, which acutely can be managed, as usual, with adenosine or cardioversion, and beta blockers in the long-term. For recurrent cases, sodium blockers, such as propafenone, or even fluoroless cardiac ablation can be used. In the context of maternal congenital heart disease, ventricular tachycardia can occur, demanding a specific approach including cardiac defibrillator implant. Unfortunately, the medical evidence in this context is scarce, and most available reviews don't have the objectivity needed to guide daily's practice. This review aims to be a straightforward guide to the approach to tachyarrhythmias in pregnancy.

Introduction: Catheter ablation is superior to drugs regarding atrial fibrillation (AF) recurrence, symptoms improvement, and mortality reduction in heart failure. POLARx™ is a novel cryoballoon, with technical improvements seeking to improve outcomes. So far, its clinical evidence is restricted to a case report. Methods: To compare the POLARx™ cryoballoon procedural safety and efficacy to the already established Arctic Front Advance PRO™ (AFAP) in a single-center cohort study, consecutive patients undergoing AF cryoablation with the POLARx™ were enrolled. Data were prospectively gathered. POLARx™ patients were compared to a historical cohort of patients submitted to AF cryoablation with the AFAP. Results: Seventy patients were analyzed, 20 in POLARx™, and 50 in the AFAP group. They all underwent first-time pulmonary vein isolation, 77% were male, 94% had paroxysmal AF, median age was 62.5 years, median CHA2DS2-VASc 1, left-atrium size 34ml/m², and 65% were receiving anticoagulation. The primary end-point, all pulmonary veins isolation, was 100% in both groups. The complication rate was similar (0% POLARx™ vs. 5.7% AFAP, p=0.39). The median total procedural time was longer in the POLARx™ group (90min vs. 60min, p<0.001), but the overall time-to-isolation (TTI) (44.8sec vs. 39sec, p=0.253) and ablation time (15min vs. 13.7min, p=0.122) was similar between POLARx™ and AFAP groups, respectively. Despite equal TTI, the POLARx™ had a lower minimal temperature reached (-57ºC vs -47ºC, p<0.001). Conclusion: The novel POLARx™ cryoballoon had similar efficacy and safety compared to the AFAP. It was also associated with longer procedural times, similar TTI, and lower minimum temperature reached.

Background: Infective endocarditis (IE) remains an expressive health problem with high morbimortali-ty rates. Despite its importance, epidemiological and microbiological data remain scarce, especially in developing countries. Aim: This study aims to describe IE epidemiological, clinical, and microbiological profile in a tertiary university center in South America, and to identify in-hospital mortality rate and predictors. Methods: Observational, retrospective study of 167 patients, who fulfilled modified Duke’s criteria during a six-year enrollment period, from January 2010 to December 2015. Primary outcome was de-fined as in-hospital mortality analyzed according to treatment received (clinical vs. surgical). Multivari-ate analysis identified mortality predictors. Results: Median age was 60years (Q1-Q3 50-71), and 66% were male. Echocardiogram demonstrated vegetations in 90.4%. An infective agent was identified in 76.6%, being Staphylococcus aureus (19%), Enterococcus (12%), Coagulase-negative staphylococci (10%), and Streptococcus viridans (9.6%) the most prevalent. Overall in-hospital mortality was 41.9%, varying from 49.4% to 34.1%, in clinical and surgical patients, respectively (p=0.047). On multivariate analysis, diabetes mellitus (OR 2.5), previous structural heart disease (OR 3.1), and mitral valve infection (OR 2.1) were all-cause death predictors. Surgical treatment was the only variable related to better outcome (OR 0.45; 95%IC 0.2-0.9). Conclusion: This study presents IE profile and all-cause mortality in a large patient’s cohort, compris-ing a 6-years’ time window, a rare initiative in developing countries. Elderly and male patients predom-inated, while Staphylococcus aureus was the main microbiological agent. Patients conservatively treated presented higher mortality than surgically managed ones. Epidemiological studies from developing countries are essential to increase IE understanding.