Association between n-3 fatty acid consumption and ventricular ectopy after myocardial infarction

Departments of Psychiatry and Behavioral Sciences and Medicine, Duke University, Durham, NC, USA.
American Journal of Clinical Nutrition (Impact Factor: 6.77). 04/2009; 89(5):1315-20. DOI: 10.3945/ajcn.2008.26829
Source: PubMed


n-3 (omega-3) Fatty acids are associated with a reduced risk of cardiovascular disease; however, the relation between dietary intake of n-3 fatty acids and ventricular arrhythmias has not been investigated among acute post-myocardial infarction (AMI) patients-a group at elevated risk of malignant arrhythmias.
The objective was to examine the association between n-3 fatty acid consumption and ventricular ectopy among AMI patients.
In 260 AMI patients, dietary intake of n-3 fatty acids was assessed by using the Harvard food-frequency questionnaire, and ventricular ectopy was estimated from 24-h electrocardiograph recordings.
A greater intake of n-3 fatty acids (eicosapentaenoic acid + docosahexaenoic acid + docosapentaenoic acid + alpha-linolenic acid) was associated with lower ventricular ectopy (beta = -0.35, P = 0.011), and this effect remained after cardiovascular comorbidities were controlled for (beta = -0.47, P = 0.003). Higher concentrations of both marine-based (eicosapentaenoic acid + docosahexaenoic acid) (beta = -0.21, P = 0.060) and plant-based (alpha-linolenic acid) (beta = -0.33, P = 0.024) fatty acids remained associated with lower ventricular ectopy after cardiovascular comorbidities were controlled for.
These findings extend existing evidence linking n-3 fatty acid consumption to a reduced risk of ventricular arrhythmias by showing that a greater intake of n-3 fatty acids may be associated with low ventricular ectopy among AMI patients.

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    • "In an epidemiologic study in 260 patients with acute myocardial infarction, intake of omega-3 fatty acids was found to correlate inversely with premature ventricular beats (Smith et al., 2009). In an epidemiologic study in 707 Alaskan natives, a significant negative association between heart rate and the omega-3 Index was seen (Ebbesson et al., 2010). "
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