The risk of developing NMSC in patients with IBD on thiopurines is only modestly elevated. The difference in pooled risk between population-based and hospital-based studies suggests the possibility that ascertainment bias could have contributed to this increased risk.

The management of atrial fibrillation (AF) has focused on anticoagulation, rhythm control and ventricular rate control. Recently, a fourth pillar of AF management has been incorporated recognising the importance of risk factor management (RFM). There are several risk factors that contribute to the development and progression of AF, these include traditional risk factors such as age, hypertension, heart failure, diabetes and valvular heart disease. However, increasingly it is recognised that obesity, sleep apnoea, hyperlipidaemia, smoking, alcohol, physical inactivity, genetics, aortic stiffness are associated with the development of AF. Importantly, several of these risk factors are modifiable. We have seen the evolution of RFM programmes which have demonstrated promising results. Indeed, the evidence is now so compelling that major clinical guidelines strongly advocate that aggressive treatment of these risk factors as a key component of AF management. Patients with AF who comprehensively managed their risk factors demonstrate greater reduction in symptoms, AF burden, more successful ablations and improved outcomes with greater AF freedom. In this article, we will review the evidence for the association between cardiac risk factors and AF and assess the burgeoning evidence for improved AF outcomes associated with aggressive cardiac RFM.

Bradyarrhythmias are an important cause of mortality in heart failure and previous studies indicate a mechanistic role for electrical remodelling of the key pacemaking ion channel HCN4 in this process. Here we show that, in a mouse model of heart failure in which there is sinus bradycardia, there is upregulation of a microRNA (miR-370-3p), downregulation of the pacemaker ion channel, HCN4, and downregulation of the corresponding ionic current, I f , in the sinus node. In vitro, exogenous miR-370-3p inhibits HCN4 mRNA and causes downregulation of HCN4 protein, downregulation of I f , and bradycardia in the isolated sinus node. In vivo, intraperitoneal injection of an antimiR to miR-370-3p into heart failure mice silences miR-370-3p and restores HCN4 mRNA and protein and I f in the sinus node and blunts the sinus bradycardia. In addition, it partially restores ventricular function and reduces mortality. This represents a novel approach to heart failure treatment. Heart failure is a major health problem affecting ~ 26 million people worldwide and is one of the leading causes of hospitalisation in USA and Europe, resulting in over 1 million admissions/year as a primary diagnosis 1. Heart failure patients often have a relatively fast heart rate (> 70 beats/min) 2,3. β-blocker and ivabradine treatment received by heart failure patients lowers the heart rate 4,5 , which may or may not be the mechanism underlying the protective effects of these medications 4. Nevertheless, and paradoxically, bradyarrhythmias (excessively slow heart rates and rhythms) account for up to half of the deaths of end-stage heart failure patients 6-8. In the human and animal models, there is dysfunction of the pacemaker of the heart, the sinus node, in heart failure: there is a decrease in the intrinsic heart rate (the heart rate set by the sinus node in the absence of autonomic nerve activity) and an increase in the corrected sinus node recovery time (a frequently used measure of the functioning of the sinus node) 9-13. The dysfunction of the sinus node in heart failure has been attributed to fibrosis 14 and also remodelling of ion channels and corresponding ionic currents underlying the functioning of the sinus node 10,11,15,16. In particular, it has been attributed to a downregulation of the important pacemaker ion channel, HCN4, and the corresponding funny current, I f 11,15 ; however, the cause of the remodelling is not known.

No abstract