"Aspirin is as 'good as warfarin' for most heart failure patients."

In an article with the above title,  James Gallagher the BBC's health and science reporter, reports that -

Aspirin could be as effective as more expensive drugs for heart failure patients with a normal heart rhythm, according to researchers.    Their study on more than 2,000 patients, published in the New England Journal of Medicine, said aspirin was as effective as the commonly prescribed drug warfarin.   It said each drug had risks, but they had similar benefits overall.

However, a UK cardiologist argued the risks from warfarin were less serious.    Dr Andrew Clark, from the British Society for Heart Failure and the University of Hull, told the BBC:-
"How to interpret that [the results] for individual patients means weighing the risk of stroke against the risk of haemorrhage, but also weighting that by importance.  I would regard a gastrointestinal haemorrhage requiring transfusion as being of less importance than a stroke, so would tend in favour of warfarin."

Source:  BBC         ;     New England Journal of Medicine

[Ed:  It should be pointed out that in this Canadian study the dose for Aspirin was 325mg.   In the UK the normal dose of Aspirin for blood thinning is usually in the range of 75mg - 150mg.
So check with your Doctor or Heart Failure nurse before reading too much into this report]