Fish Oil Has Benefits in Heart Failure

Supplementation with omega-3 polyunsaturated fatty acids improved left ventricular function in patients with mild-to-moderate chronic heart failure due to dilated cardiomyopathy….

According to Mihai Gheorghiade, MD, of Northwestern University in Chicago, and colleagues, after one year of treatment, patients who took the supplements had a significant improvement of 10.4% in left ventricular ejection fraction, compared with a decline of 5% in patients on placebo (P<0.001),

Omega-3 supplementation also improved peak oxygen uptake by 6.2% (versus a worsening of 4.9% with placebo) and exercise duration by 7.7% (versus a reduction of 5.8% with placebo), the researchers reported online in the Journal of the American College of Cardiology.

Gheorghiade and his colleagues wrote, “None of the patients taking the supplements moved to a higher New York Heart Association functional class, whereas 28.8% of those on placebo worsened (P<0.001)."

The findings add support to a larger trial, GISSI-HF, that showed that long-term treatment with a lower dose of omega-3 polyunsaturated fatty acids reduced mortality and cardiovascular hospitalizations in patients with chronic heart failure. But until the current trial was conducted, it had been unknown whether supplementation would improve left ventricular function.

One hundred thirty-three patients were recruited from a single clinic at the University of Brescia in Italy. All had NYHA class I or II heart failure due to nonischemic dilated cardiomyopathy with minimal symptoms. All were on standard, evidence-based therapy with an ACE inhibitor, an angiotensin II receptor blocker, a beta-blocker, and furosemide. Many patients were also taking an aldosterone receptor blocker.

The researchers randomized the patients in roughly equal numbers to supplementation with omega-3 polyunsaturated fatty acids or placebo. Active treatment was given in 1-gram capsules containing 850 to 882 mg of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) ethyl esters. Patients took five capsules daily for the first month followed by two capsules daily for the rest of the study.

After 12 months, there were significant between-group differences in left ventricular ejection fraction (the primary endpoint), peak oxygen consumption, exercise duration, and functional class (P<0.001 for all).

Left ventricular diastolic function, according to deceleration time and diastolic function score, improved in the supplementation group and worsened in the placebo group.

Consistent with experimental evidence that omega-3 polyunsaturated fatty acids reduce inflammation, levels of three inflammatory cytokines (tumor necrosis factor [TNF]-alpha, interleukin-6, and interleukin-1) significantly increased in the placebo group and decreased in the supplementation group (P<0.001). All of these changes may have been responsible for the significant reduction in the rate of cardiovascular hospitalizations in the supplementation group (6% versus 30%, P=0.0002), the researchers noted.

Supplementation was well tolerated, with no serious adverse events.

The furosemide dose was maintained in 61% of the supplementation group and reduced in 39%. In contrast, the dose was maintained in 76% of the placebo group and increased in 24%. There were no changes to any of the other medications.

In an accompanying editorial, W.H. Wilson Tang, MD, and Michael Samara, MD, of the Cleveland Clinic, noted that the question of whether higher doses of omega-3 polyunsaturated fatty acids (PUFAs) could achieve better outcomes remained unknown.

“This is a critical question to address, since prescription-strength, high-dose omega-3 PUFA regimens differ significantly from the lower and inconsistent dosages found in over-the-counter supplements,” they wrote.

“In other words, simply telling patients to take ‘fish-oil’ supplements without understanding the adequacy of dosing is unlikely to yield the same benefits as promised in the current study.”

• Note that this study provides evidence for beneficial effects of high dose supplemental omega-3 polyunsaturated fatty acids in patients with heart failure due to nonischemic dilated cardiomyopathy.
• Point out that the benefit in this study was seen in patients with minimal symptoms in response to evidence-based medical therapy.

Nodari S, et al “Effects of n-3 polyunsaturated fatty acids on left ventricular function and functional capacity in patients with dilated cardiomyopathy” J Am Coll Cardiol 2011; DOI: 10.1016/j.jacc.2010.11.017.