Surveys and registries are widely used in medicine as valuable tools to integrate the information from randomized and observational studies. Early after its introduction in daily practice and parallel to its escalating popularity, catheter ablation of atrial fibrillation has been the subject of several surveys and registries. Over the years, relevant aspects associated with atrial fibrillation ablation have been investigated using these tools, including procedural safety and efficacy, discontinuation of anticoagulation therapy and risk of stroke postablation, and outcomes in special populations. The aim of this article is to provide a comprehensive review of the contributions offered by surveys and registries in catheter ablation of atrial fibrillation over the past 15 years.

Liver and heart disease are major causes of death worldwide. It is known that metabolic alteration causing type 2 diabetes (T2D) and Nonalcoholic fatty liver (NAFLD) coupled with a derangement in lipid homeostasis, may exacerbate hepatic and cardiovascular diseases. Some pharmacological treatments can mitigate organ dysfunctions but the important side effects limit their efficacy leading often to deterioration of the tissues. It needs to develop new personalized treatment approaches and recent progresses of engineered RNA molecules are becoming increasingly viable as alternative treatments. This review outlines the current use of antisense oligonucleotides (ASOs), RNA interference (RNAi) and RNA genome editing as treatment for rare metabolic disorders. However, the potential for small non-coding RNAs to serve as therapeutic agents for liver and heart diseases is yet to be fully explored. Although miRNAs are recognized as biomarkers for many diseases, they are also capable of serving as drugs for medical intervention; several clinical trials are testing miRNAs as therapeutics for type 2 diabetes, nonalcoholic fatty liver as well as cardiac diseases. Recent advances in RNA-based therapeutics may potentially facilitate a novel application of miRNAs as agents and as druggable targets. In this work, we sought to summarize the advancement and advantages of miRNA selective therapy when compared to conventional drugs. In particular, we sought to emphasise druggable miRNAs, over ASOs or other RNA therapeutics or conventional drugs. Finally, we sought to address research questions related to efficacy, side-effects, and range of use of RNA therapeutics. Additionally, we covered hurdles and examined recent advances in the use of miRNA-based RNA therapy in metabolic disorders such as diabetes, liver, and heart diseases.

Background: Several studies have confirmed the equivalence of the microvolt T‐wave alternans (mTWA) and the electrophysiology (EPS) tests in cardiac disease. No data are available in populations of competitive athletes with arrhythmias that might jeopardize the pursuit of their professional career. Methods: We prospectively studied 100 trained competitive athletes, including elite types (72/100), (mean age ± standard deviation: 26.1 ± 4.5 years). Forty‐eight of them were wholly normal (Group A, mean age: 24.5 ± 8.5 years) and 52 of them had severe arrhythmias (Group B, mean age: 28.2 ± 11.5 years) and were symptomatic in 85% of cases for prolonged palpitations and syncope, but lacked any overt structural heart disease at standardized cardiological screening.All athletes were evaluated with the microvolt T‐wave alternans exercise–stress test, using the Heart Wave System with Microvolt Sensors. Group B underwent EPS to evaluate inducibility to sustained ventricular tachycardia (VT) during programmed electrical stimulation. Results: In Group A, the mTWA outcome was determinate in 45 subjects (94%) and indeterminate in 3 (6%). No symptomatic event was reported in a follow‐up of 36.1 months. In Group B, the mTWA test was positive in 7 symptomatic subjects (15%), indeterminate in 3 (7%), and negative for the remaining 42 subjects (76%). Forty‐one of 42 negative mTWA subjects were also negative in the EPS test, without any syncope or sustained VT during 25.3 months of follow‐up. In the positive mTWA test subjects, 5 (72%) were positive for inducibility of rapid sustained monomorphic VT in EPS, 1 was positive for severe sustained atrial tachyarrhythmias, and 1 refused EPS. We were able to pronounce a correct diagnosis of lymphocytic myocarditis for only 1 mTWA and EPS‐positive subject. For the other 4 positive patients with arrhythmogenic micropathology, severe arrhythmic events were revealed in the follow‐up and aggressive hybrid treatment was necessary. Conclusion: Microvolt‐TWA study seems to be a useful, noninvasive, and feasible tool for evaluating arrhythmic risk in the athletic population. The mTWA test showed a high negative predictive value, using both EPS and the follow‐up observation for severe arrhythmic cardiac events as an endpoint. The positive predictive value was present in a limited number of cases that were, however, subjects with a high risk of sudden arrhythmic death.

The aim of this study was to determine whether the time of occurrence of sudden death exhibits a circadian rhythm depending on its different anatomoclinical causes. A longitudinal prospective investigation of 610 nonhospitalized subjects who died suddenly in the Emergency Room of Ferrara Hospital between January 1983 and December 1990 was conducted. All subjects underwent autopsy. Sudden death was classified on the basis of the following pathological causes; acute myocardial infarction, acute myocardial failure, intracerebral hemorrhage, rupture of aortic aneurysm, pulmonary embolism, and clinical causes, i.e., arrhythmia and circulatory failure. The investigated cases were stratified into 2 groups according to age; Group A = age < 70 years (n = 301, 49.3%), and Group B = age > or = to 70 (n = 309, 51.7%). The assessment of circadian rhythmicity was performed utilizing the single cosinor method. The results by cosinor analysis found a circadian rhythmicity for cases of sudden death (peak at 14.04, n = 610, p = 0.036), and in particular for females (peak at 13.12, n = 200, p = 0.004). Spectral analysis detected a statistical ultradian cycle in males having an 8-hour period (p = 0.015). A statistically significant circadian rhythm was found for cases of sudden death due to acute myocardial infarction (peak at 15.28, n = 330, p = 0.013), pulmonary embolism (peak at 11.46, n = 56, p = 0.003) and arrhythmia (peak at 13.08, n = 291, p = 0.04). In Group A no significant circadian rhythm was found, whereas in Group B a significant rhythmicity was found for sudden death from cardiac causes at 13.32 (n = 249, p = 0.015), from myocardial infarction at 15.02 (n = 154, p = 0.018) and from arrhythmia at 13.07 (n = 122, p = 0.014). Different circadian patterns of onset of sudden death may be shown in various subgroups of patients, due not only to different pathophysiologic mechanisms but also to anatomo-clinical aspects.

Class IC antiarrhythmic drugs (AADs) currently represent a cornerstone in the therapy of atrial fibrillation, both for the restoration of sinus rhythm and for the prophylaxis of long-term relapses. They also play an important role in the treatment of idiopathic ventricular arrhythmias. Following the results of the Cardiac Arrhythmia Suppression Trial study, flecainide and by extension the other Class IC AADs were contraindicated in patients with ischaemic and structural heart disease, due to their pro-arrhythmic effect and the consequent increase in mortality observed in the study. Recent studies carried out on patients with chronic coronary heart disease without previous heart attacks and/or residual ischaemia have shown a good safety profile for this class of drugs. In addition, other studies have shown excellent efficacy in the absence of pro-arrhythmic effects of Class IC AADs in patients with structural heart disease such as arrhythmogenic right ventricular cardiomyopathy (ARVC) and tachy-cardiomyopathy. The purpose of this review is to evaluate the appropriate use of Class IC AADs in the different patient subgroups, in the light of the evidence and new diagnostic and therapeutic tools available.