There has been ongoing controversy as to whether aspirin should be used in patients with chronic heart failure (CHF). The argument for aspirin is that many patients have underlying coronary disease, and aspirin prevents reinfarction and other vascular events. Arguments against the routine use of aspirin are that many CHF patients do not have underlying coronary disease, and that the benefit of aspirin lessens after the first 6 to 12 months after infarction. Also, several analyses suggest that aspirin may actually worsen outcomes in CHF patients, possibly because it inhibits prostaglandins, with resulting adverse hemodynamic and renal effects. Two recent prospective randomized studies have found that aspirin is associated with more frequent hospitalizations for worsening heart failure, although it did not have an adverse effect on vascular events. These results suggest that aspirin should not be routinely used in CHF patients and be avoided in those with refractory CHF, but that it may be beneficial in patients with recent infarction or multiple vascular risk factors.