[Cardiac toxicity of fluoro-uracil. Typical and atypical aspects. Apropos of 8 cases].

The cardiac toxicity of 5 fluoro-uracil, an antimitotic agent widely used in various protocols, has been known for 16 years. Several cases have been reported in the literature, leading to the suggestion, without formal evidence, that the chief mechanism responsible for this cardiac toxicity is "classical" coronary spasm. However, certain clinical aspects already described may shed doubt on this theory. On the basis of 8 cases, the authors report different clinical pictures all caused by cardiac toxicity of 5FU. It is of interest to note that chest pain with the classically described electrocardiographic changes did not apply in the majority of cases. The commonest pattern was asymptomatic electrocardiographic abnormalities and/or arrhythmias without angina. Among the reported cases, one patient had pain with electrocardiographic abnormalities, recurrent after the withdrawal of 5FU and resistant to maximal medical treatment, despite the absence of any coronary disease or signs of spasm. One patient had a first myocardial infarction, later rechallenge with the drug resulting in failure. In another patient, with known coronary disease, 5FU probably cause cardiogenic shock. In total, some of our cases, as well as other features described in the literature, raise questions as to the pathophysiology of the cardiac toxicity of 5FU.