Bradyarrhythmias and pacemakers

### What you need to know Bradyarrhythmias are heart rhythms with a rate of <60 beats/min, commonly due to conduction abnormalities in the heart such as sinus node disease or atrioventricular block.1 There is increased risk of sudden cardiac death due to slowing or stopping of the heart, and of falls, especially in older people, due to fainting. Worldwide over one million pacemakers are implanted annually for bradyarrhythmias.23 With an ageing population this is expected to increase.4 New technologies such as leadless pacemakers are being introduced, which general physicians will increasingly encounter. This update will help physicians identify and manage bradyarrhythmias appropriately and will familiarise them with an increasingly complex array of pacemakers. Fig 1 Position of sinus and atrioventricular nodes in the heart, with ECG features and causes of sinus node disease, first degree heart block, and atrioventricular node disease are described. ### Sources and selection criteria We used the 2016 European Society of Cardiology (ESC) heart failure guidelines,29 the 2013 ESC13 and 2012 American College of Cardiology Foundation (ACCF)/American Heart Association (AHA)/Heart Rhythm Society (HRS) pacing guidelines16 and the 2014 National Institute …