However aspirin was introduced before clinical trials as the investigators know them now were run. Systematic review of the trials of aspirin in heart failure has shown that its use does not increase survival, and there is no evidence to recommend its routine use. Another important finding was that use of aspirin may reduce the beneficial effects of ACE inhibitors which do have a mortality benefit, and that aspirin was associated with an increase in hospitalisation for heart failure compared to other drugs which prevent clots or placebo.