Just happened to read this yesterday. So yes there is good evidence in that
direction.

Bill

http://www.medscape.com/viewprogram/4605_pnt

Omega-3 Fatty Acids and Cardiovascular Disease

Jan Breslow, MD

There are a number of studies to support fish intake as a preventive measure
in cardiovascular disease (CVD). In a prospective study of healthy males, low
baseline total n-3 fatty acid, EPA, and DHA blood levels are associated with a
greater risk of sudden death.[29] The DART (Diet and Reinfarction Trial) study
encouraged male myocardial infarction survivors to consume more oily fish
(approximately 500 to 800 mg/day of n-3 fatty acids) and found a 29% reduction
in total mortality. A subgroup from this study chose to take fish oil capsules
providing 450 mg EPA and DHA per day; this group had a 62% reduction in
CVD-related death and a 56% reduction in all-cause mortality.[30,31] The GISSI
prevention trial, an Italian study of post-myocardial infarction patients,
showed that after 3.5 years, those receiving n-3 fatty acids (850 mg/day) had
a 20% reduction in overall mortality, 30% reduction in coronary mortality, and
45% reduction in sudden death.[32]

The proposed mechanisms by which n-3 fatty acids might influence CVD are via
anti-arrhythmic properties, decreasing blood pressure, lowering triglyceride
levels, stimulating endothelial-derived nitric oxide, decreasing platelet
aggregation, and/or decreasing pro-inflammatory eicosanoids.[33] There is
evidence to suggest that the n-3 fatty acids prevent arrhythmias by
stabilizing the myocardium.[34]

A recent multicenter randomized placebo-controlled trial reported more
ventricular tachycardia (VT) and ventricular fibrillations (VF) in patients
with implantable cardioverter defibrillators (ICD) who were randomized to
receive 1.3 g EPA and DHA per day compared to controls who received olive oil.
The fish oil group reported more VT and VF events; however, the fish oil group
had lower total mortality (although not significant, P = .16) and fewer
hospitalizations for a neurologic conditions (P = .04). If the mechanism for
fish oil's benefits in decreasing sudden death is anti-arrhythmic, it may not
be due to decreased risk of VT and VF.[35]

Breslow's research suggests that DHA (supplemented at a level of 2 g/d)
favorably alters CVD risk factors in overweight and obese individuals. Future
research should review the role of n-3 fatty acids in secondary prevention as
well as in the immediate, post-MI period because the greatest reduction of
cardiac mortality is achieved in the first 9 months. Research must control for
the type of n-3 fatty acid studied (vegetable vs marine source), EPA vs. DHA,
and compare n-6 to n-3 fatty acids. Future investigations are required to
further evaluate the anti-arrhythmic effects of n-3 fatty acids, as well as
their systemic anti-inflammatory properties and immune modulatory effects.