• Kidney
• cardiac arrhythmia
• renal dialysis
• sudden cardiac death
• implantable cardioverter-defibrillator
• atrial arrhythmias
• atrioventricular block
• renal disease

Chronic kidney disease (CKD) is defined as evidence of kidney damage or a glomerular filtration rate (GFR) ≤60 ml/min/1.73 m² (table 1). The most common causes of CKD are hypertension and diabetes mellitus. The many causes of CKD are associated with different varying prognoses. Patients with adult polycystic kidney disease have a 50% lifetime risk of needing dialysis compared with 25% for type 1 diabetes and <5% for type 2 diabetes. Dialysis is usually considered when GFR falls below 10 ml/min/1.73 m² but the exact timing will often be dictated by clinical circumstances. This may be refractory oedema, hyperkalaemia and acidosis, uraemia or unacceptable symptoms. Dialysis only partially replaces the excretory function of the kidneys and so the morbidity and mortality associated with CKD are not completely resolved with dialysis. In fact, mortality in the dialysis patient is very high. The life expectancy of a 25-year-old dialysis patient is 12 years, compared with 32 years for an age equivalent transplant recipient and 52 years for a 25-year-old in the general population.1 Even patients with CKD stage 5 will only have a 20–25% chance of surviving long enough to require dialysis. The greatest cause of death in CKD is premature cardiovascular disease. For example, fewer than one in five patients with heart failure will have a normal GFR and 38% of the prevalent dialysis population have coronary artery disease (CAD) (17% previous myocardial infarction, 23% symptoms of angina).2 Both cardiac and renal systems appear to be completely interdependent, further emphasising the concept of the ‘cardiorenal syndrome’. This is highlighted when considering arrhythmias in patients with impaired renal function.

The arrhythmia burden of the patient with CKD is high, with the single greatest contributor to mortality in end stage renal disease (ESRD) being sudden cardiac death (SCD). SCD accounts for …