Aspirin, angiotensin converting enzyme inhibitors and cardiac failure.

The possible negative therapeutic interaction between aspirin and angiotens in converting enzyme inhibitors arose from the conclusions of several exper imental studies and retrospective analysis of large scale mortality trials with converting enzyme inhibitors. Some experimental results show inhibition of the vasodilatation of converti ng enzyme inhibitors, increase in pulmonary pressures. vascular resistances and blood pressure, and degradation of renal function and exercise capacit y. However, other studies did not confirm these results. In large scale therapeutic trials, some retrospective analyses, but not all of them, have shown less benefit on morbi-mortality of converting enzyme i nhibitors in patients on aspirin. The differences between the doses of aspi rin, the type and dosage of the converting enzyme inhibitors and neuro-horm onal activation of the patients could explain the discordant results. The results of randomised trials are awaited but, in the meantime, it is lo gical to propose small doses of aspirin (less than or equal to 100 mg/day) for patients with cardiac failure and atherosclerosis and to avoid the asso ciation in all the other patients.