[Cardiac toxicity of 5-fluorouracil. Two cases]

Major ventricular repolarization disorders without evidence of myocardial infarction developed in 2 patients during the first course of a 5-fluorouracil (5-FU) treatment in doses of 1,000 mg/m2/day. Anginal pain was present in one patient but not in the other. The electrical abnormalities persisted for more than 6 weeks in one case. Explorations carried out 2 and 6 weeks later respectively under calcium inhibitors showed absence of coronary artery stenosis, negative methyl ergonovine test (even after 5-FU infusion in one patient) and normal left ventricular kinetics. The mechanism of cardiac toxicity is discussed on the basis of these data: some elements support a coronary spasm and others direct myocardial toxicity.