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.