OBJECTIVES: This study was designed to test the effects of n-3 polyunsaturated fatty acids (PUFAs) on left ventricular (LV) systolic function in chronic heart failure (HF) due to nonischemic dilated cardiomyopathy (NICM).

BACKGROUND: One hundred thirty-three patients with NICM and minimal symptoms on standard therapy were randomized to 2 g of n-3 PUFAs or placebo. LV function and functional capacity were assessed prospectively by echocardiography and cardiopulmonary exercise testing at baseline and at 12 months after randomization.

METHODS: Patients with chronic HF due to NICM and minimal symptoms while receiving evidence-based therapy were enrolled. LV function and functional capacity were assessed prospectively by echocardiography, cardiopulmonary exercise test, and New York Heart Association functional class at baseline and at 12 months after randomization to either 2 g of n-3 PUFAs or placebo.

RESULTS: At 12 months after randomization, the n-3 PUFAs group and the placebo group differed significantly (p <0.001) in regard to: 1) LV ejection fraction (increased by 10.4% and decreased by 5.0%, respectively); 2) peak VO(2) (increased by 6.2% and decreased by 4.5%, respectively); 3) exercise duration (increased by 7.5% and decreased by 4.8%, respectively); and 4) mean New York Heart Association functional class (decreased from 1.88 ± 0.33 to 1.61 ± 0.49 and increased from 1.83 ± 0.38 to 2.14 ± 0.65, respectively). The hospitalization rates for HF were 6% in the n-3 PUFAs and 30% in the placebo group (p = 0.0002).

CONCLUSIONS: In patients with NICM and minimal symptoms in response to evidence-based medical therapy, n-3 PUFAs treatment increases LV systolic function and functional capacity and may reduce hospitalizations for HF. Given these promising results, larger studies are in order to confirm our findings.