Cardiovascular disease is the most common cause of death in haemodialysis (HD)patients, and half of these deaths are due to sudden cardiac death caused by ventricular arrhythmias. HD patients have an attenuated heart rate variability (HRV) and a high frequency of ventricular arrhythmias, both of which are predictors of sudden cardiac death(SCD). n-3 polyunsaturated fatty acids (PUFA) improves HRV and reduces the risk of SCD. n-3 PUFAs are obtained from fatty fish and fish oil and are incorporated into cell membranes after long-term ingestion. However, it is not known if this incorporation is essential or merely serves as storage for n-3 free PUFAs to be release during for instance myocardial ischaemia.