The Effect of Omega-3 Polyunsaturated Fatty Acids in Congestive Heart Failure

A diet rich in Omega-3 (fish oil) reduces plasma triglycerides and the risk for ischemic heart disease. Recently, a large trial evaluating treatment with Omega 3 in heart failure patients suggested that omega 3 may lower the risk of death from CHF. The mechanism of this potential benefit is not well understood.

Methods:

Forty patients will be enrolled in the study. Twenty patients will receive Omega 3 (lovaza 4 gm a day) and 20 patients will receive placebo. All subjects will have assessment of their exercise capacity and blood vessel function before and after an 8 week treatment period. About 4 table spoons of blood will be drawn throughout the study.

Expected results:

The investigators believe that omega 3 may improve the ability to exercise and improve blood vessel function.

A diet rich in Omega-3 polyunsaturated fatty acids Omega 3 reduces plasma triglycerides and the risk for ischemic heart disease1, and may exert direct antiarrhythmic effect on the myocardium 2-9. A post-hoc analysis of the GISSI-Prevenzione trial demonstrated a reduction in all-cause and sudden mortality in a subgroup of nearly 2000 post-infarction patients with left ventricular dysfunction 10. This provocative finding has now been prospectively studied in a large-scale, randomized, double-blind study designed to investigate the effects of Omega 3 on mortality and morbidity in patients with symptomatic heart failure (the GISSI Heart Failure project). The results of the GISSI-HF trial demonstrate that 1 g per day of Omega 3 is associated with 9% reduction in mortality and cardiovascular admissions in patients with predominantly systolic heart failure, when added to optimal medical therapy11.

The mechanism(s) underlying these beneficial effects remains to be elucidated and will be critical in fully exhausting the therapeutic benefits of Omega 3 in CHF. We have recently demonstrated that lipid oxidation during acute exercise is altered in patients with CHF 12 and that the degree of this alteration carries prognostic significance. It is conceivable that Omega 3 modulates lipid oxidation during exercise and thereby favorably effect outcome. Accordingly we propose to study the effect of Omega 3 on lipid oxidation during exercise in CHF. We will further examine VO2 and endothelial function at present the principal surrogate markers for survival in CHF 13.

Eligibility Criteria:
Inclusion Criteria:

All subjects with CHF due to systolic dysfunction followed at the outpatient facilities of Columbia University Medical Center will be screened and subjects will be asked to participate if the following criteria are met:

* Older than 18 years.
* Symptomatic heart failure (New York Heart Association functional class II-III).
* Ischemic or non-ischemic cardiomyopathy.
* Left ventricular ejection fraction (EF) 40% or lower.
* Peak oxygen uptake (VO2, peak) between 10 and 17 mL O2/min/kg.
* Be on appropriate, stable medical treatments for heart failure, including (unless shown to be intolerant) a diuretic, an angiotensin-converting enzyme inhibitor and/or angiotensin-receptor blocker and a beta-blocker, pacemaker or ICD or CRT.

Exclusion Criteria:

* Unable to perform treadmill exercise
* Pregnancy
* Recent myocardial infarction (within 3 months).
* Clinically significant angina.
* Hospitalization for heart failure requiring intravenous treatments within 30 days.
* Allergy to fish