n-3 fatty acids and ventricular arrhythmias in patients with ischaemic heart disease and implantable cardioverter defibrillators

Aim To investigate the relationship between serum content of n-3 polyunsaturated fatty acids (PUFA) and the incidence of ventricular arrhythmias in patients with an implantable cardioverter defibrillator (ICD). Methods We included 98 patients with ischaemic heart disease and an ICD. The numbers of ventricular fibrillation (VF) and ventricular tachycardia (VT) events were assessed during a 12-month period and related to the concentration of n-3 PUFA in serum phospholipids. Results Patients with more than one arrhythmic event had significantly lower n-3 PUFA levels compared with patients without arrhythmias (mean 7.1% vs 9.2%, P < 0.01). Dividing the patients into quintiles according to their n-3 PUFA level those with the lowest content of n-3 PUFA had more ventricular arrhythmias than patients with the highest concentration of n-3 PUFA (mean 1.3 event vs 0.2 event, P < 0.05). Conclusion Patients with a low content of n-3 PUFA in serum had a higher incidence of ventricular arrhythmias compared with patients with high serum levels of n-3 PUFA. The data suggest that the protection offered by n-3 PUFA against sudden cardiac death observed in previous studies is mediated by a direct antiarrhythmic effect of n-3 PUFA. (c) 2005 The European Society of Cardiology. Published by Elsevier Ltd. All rights reserved.