The role of n-3 PUFAs in preventing the arrhythmic risk in patients with idiopathic dilated cardiomyopathy.
BACKGROUND
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.


METHODS
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.


RESULTS
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.


CONCLUSIONS
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.
Nodari
Savina
S
Section of Cardiovascular Diseases, Department of Experimental and Applied Medicine, University of Brescia, c/o Spedali Civili, P.zza Spedali Civili, 25100, Brescia, Italy.
Metra
Marco
M
Milesi
Giuseppe
G
Manerba
Alessandra
A
Cesana
Bruno Mario
BM
Gheorghiade
Mihai
M
Dei Cas
Livio
L
D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology*; D001145:Arrhythmias, Cardiac / Q000209:etiology / Q000517:prevention & control*; D002311:Cardiomyopathy, Dilated / Q000150:complications*; D002395:Catecholamines / Q000097:blood; D016207:Cytokines / Q000097:blood / Q000187:drug effects; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D004311:Double-Blind Method; D004338:Drug Combinations; D015118:Eicosapentaenoic Acid / Q000494:pharmacology*; D015716:Electrocardiography, Ambulatory; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors
D000889:Anti-Arrhythmia Agents; D002395:Catecholamines; D016207:Cytokines; D004338:Drug Combinations; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid