The Role of n-3 PUFAs in Preventing the Arrhythmic Risk in Patients with Idiopathic Dilated Cardiomyopathy

Section of Cardiovascular Diseases, Department of Experimental and Applied Medicine, University of Brescia, c/o Spedali Civili, P.zza Spedali Civili, 25100, Brescia, Italy.
Cardiovascular Drugs and Therapy (Impact Factor: 3.19). 11/2008; 23(1):5-15. DOI: 10.1007/s10557-008-6142-7
Source: PubMed


N-3 polyunsaturated fatty acids (n-3 PUFAs) intake is associated with a reduction in sudden cardiac death in patients with ischemic heart disease. Their effects in patients with heart failure caused by idiopathic dilated cardiomyopathy (IDC) are unknown.
We compared with placebo the effects of n-3 PUFAs administration in 44 patients with IDC and with frequent or repetitive ventricular arrhythmias at Holter monitoring using a randomized, double-blind design. Arrhythmic risk was assessed by microvolt T-wave analysis (MTWA), signal averaged ECG (SAECG), Holter monitoring, power spectral analysis of heart rate (HR) variability, catecholamine and cytokine plasma levels, at baseline and after 6 months.
At MTWA, 7/12 patients (58%) initially positive became negative after n-3 PUFAs while one patient became positive after placebo (p = 0.019). N-3 PUFAs administration was also associated to normalization of SAECG (11/15 patients, p < 0.0015), decrease in non-sustained ventricular tachycardia (NSVT) episodes (p = 0.0002) and NSVT HR (p = 0.0003), improvement in HR variability and decrease in catecholamine and cytokine plasma levels. The ratio of plasma n-6 PUFAs to n-3 PUFAs decreased from 12.01 to 3.48 after n-3 PUFAs.
N-3 PUFAs administration is associated with favorable effects on parameters related to arrhythmic risk in patients with idiopathic dilated cardiomyopathy. These results are consistent with antiarrhythmic activity independent from their antiischemic effects.

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    PLoS ONE 02/2014; 9(2):e88103. DOI:10.1371/journal.pone.0088103 · 3.23 Impact Factor
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    • "In addition to these direct effects on the generation and duration of the action potential, other less direct mechanisms of actions have been proposed. There is also evidence for antiarrhythmic effects mediated through a reduced production of proarrhythmic eicosanoids, reduced levels of circulating catecholamines [38], and a reduced agonist affinity of beta-receptors [17]. The latter observation might be one of the mechanisms responsible for an improvement in the cardiac sympathetic-vagal balance, revealed clinically as a reduction in the mean heart rate (HR) [39] as well as an increase in HR variability [40]. "
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    12/2012; 2012(8):303456. DOI:10.1155/2012/303456
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    • "Extensive studies on the potential effects of fish oil omega-3 poly unsaturated fatty acids (ω-3 PUFA) on cardiac rhythm have provided controversial results (von Schacky, 2008). While some interventional studies reported either no effect or even promotion of arrhythmias in some subgroups of patients with heart disease (Raitt et al., 2005; Coronel et al., 2007; Den Ruijter et al., 2007; Cheng and Santoni, 2008), other studies have reported beneficial effects of ω-3-PUFAs on cardiac rhythm resulting in a reduction in the incidence of sudden cardiac death or mortality (London et al., 2007; Cheng and Santoni, 2008; Nodari et al., 2009). It seems that fish oil fatty acids may exert either pro-or anti-arrhythmic effects, probably depending on different underlying mechanisms for the arrhythmias. "
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