Article

Effect of n-3 fatty acids from fish on electrocardiographic characteristics in patients with frequent premature ventricular complexes.

Wageningen Centre for Food Sciences (WCFS) and Division of Human Nutrition, Wageningen University, Wageningen, The Netherlands.
British Journal Of Nutrition (Impact Factor: 3.3). 07/2005; 93(6):787-90. DOI: 10.1079/BJN20051429
Source: PubMed

ABSTRACT n-3 Fatty acids may protect against heart disease mortality by preventing fatal arrhythmias. Underlying effects on cardiac electrophysiology may be demonstrable in the standard electrocardiogram (ECG) and provide insight into the mechanism. Therefore, we investigated the effect of dietary n-3 fatty acids on heart-rate-corrected QT interval, T-loop width, spatial QRS-T angle and spatial U-wave amplitude in patients with frequent premature ventricular complexes. Seventy-four patients received either capsules providing 1.5 g n-3 fatty acids daily or placebo for approximately 14 weeks. ECG were recorded before and after intervention. None of the ECG characteristics was significantly affected by treatment. The present results do not provide additional support for the hypothesis that n-3 fatty acids prevent cardiac arrhythmia through generic electrophysiologic effects on heart cell membranes. However, we cannot exclude effects of n-3 fatty acids on clinical relevant endpoints that are not easily detected by prior changes in the ECG.

0 Bookmarks
 · 
50 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: 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.
    American Journal of Clinical Nutrition 04/2009; 89(5):1315-20. · 6.50 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Patients treated with haemodialysis are at high risk of sudden cardiac death (SCD) often caused by arrhythmias. Atrial fibrillation (AF) is frequent among haemodialysis patients and is associated with increased mortality. Prolonged QTc is a risk marker of ventricular arrhythmia and is thereby associated with SCD. Studies have suggested that n-3 PUFA may have an antiarrhythmic effect, but the exact mechanism is not clear. The aim of this study was to examine whether AF was associated with n-3 PUFA in plasma phospholipids and whether supplementation with n-3 PUFA would shorten the QTc interval in haemodialysis patients compared to placebo. In a double-blinded randomised, placebo-controlled intervention trial 206 haemodialysis patients with CVD were treated with 1·7 g n-3 PUFA or placebo (olive oil) daily for 3 months. Blood samples and electrocardiogram evaluations were carried out at baseline and after 3 months. The QT interval, PQ interval and heart rate were measured in all patients with sinus rhythm (SR). At baseline 13 % of patients had AF. The content of the n-3 PUFA, DHA, was significantly lower (P < 0·05) in serum of patients with AF compared with patients with SR. Thus, the DHA content was independently negatively associated with AF. Supplementation with n-3 PUFA did not shorten the QT interval significantly compared to the placebo group (P = 0·42), although subgroup analysis within the n-3 PUFA group revealed a shortening effects on QTc (P = 0·01). In conclusion, an inverse association was found between the presence of AF and the plasma DHA in haemodialysis patients. Intervention with n-3 PUFA did not shorten the QTc interval compared to placebo.
    The British journal of nutrition 07/2011; 107(6):903-9. · 3.45 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Regular physical activity (PA) has shown substantial cardiac benefits. We sought to investigate whether habitual PA is associated with changes of the electrical action potential duration, as it is represented by the QT duration on a rest ECG, in a population based sample of middle-aged and elderly individuals of Ikaria island. In a cross-sectional survey 1071 inhabitants of Ikaria Island (65 ± 13 years, 47% males) were enrolled. PA was estimated by means of IPAQ classifying the participants into low, moderate and vigorous group. QT duration was measured from a surface electrocardiogram; while using Bazett's formula the heart-rate-corrected QT (QTc) was calculated. Among participants, 85% reported at least moderate PA levels. Women in the 'vigorous' and 'moderate' PA level compared to those in the 'low' PA level had significantly shorter QTc (408 ± 2 ms vs. 411 ± 1 ms vs. 419 ± 2 ms, P = 0.001, respectively). In contrast, no significant difference in QTc according to PA levels was observed in men (P = 0.053). Linear regression analysis revealed that PA level was significantly associated with shorter QTc in women after adjustment for established confounders; while no such association was evident in men. Furthermore, compared to the 'low' PA group, women in the 'vigorous' PA group were 5.5-times less likely to have QTc interval above 450 ms (P = 0.031). Increased PA is associated with shorter QTc interval only in middle-aged and elderly women of Ikaria Island irrespectively of participant's habits or medical conditions, illustrating gender differences in the cardioprotective effect of habitual exercise.
    QJM: monthly journal of the Association of Physicians 07/2011; 104(12):1035-43. · 2.36 Impact Factor

Full-text (2 Sources)

View
0 Downloads
Available from
Sep 16, 2014