levoleucovorin and Arrhythmias--Cardiac

Cardiotoxicity is a rare but serious complication of 5-fluorouracil therapy. Coronary vasospasm and, less frequently, acute myocarditis have been identified as underlying mechanisms. We report a case of severe toxicity in a relatively young and fit male patient being treated for metastatic colonic adenocarcinoma displaying characteristics that cannot be explained by either mechanism alone.

Topics: Adenocarcinoma; Antimetabolites, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Arrhythmias, Cardiac; Cardiomyopathy, Dilated; Cardiovascular Agents; Colonic Neoplasms; Coronary Vasospasm; Fluorouracil; Heart Diseases; Humans; Leucovorin; Liver Neoplasms; Male; Middle Aged; Myocarditis; Organoplatinum Compounds; Oxaliplatin; Treatment Outcome; Ventricular Dysfunction, Left

High-dose methotrexate (HD-MTX) is widely used in combination chemotherapy and can be handled without life-threatening toxicity in combination with leucovorin (LV) rescue. However, in an experimental animal model for testing of short-term HD-MTX effects in anesthetized rats, the authors previously demonstrated intolerable toxicity and death within a few hours in some animals. Serum levels were below levels routinely found in patients on HD-MTX treatment. This study was aimed at disclosure of possible mechanisms for acute toxicity of MTX in rats. The previously determined maximum tolerated dose of 5 g/kg MTX was used as the test dose. The animals that died showed sudden reduction in heart rate and blood pressure. LV, 1 g/kg infused immediately prior to MTX, changed MTX elimination kinetics, but did not change the acute toxicity. The data of this study together with additional evidence obtained in the experimental model, suggest that MTX acute toxicity may not be related to its antiproliferative effect, but rather to perturbation of endothelial cell and platelet function.

Topics: Animals; Antimetabolites, Antineoplastic; Arrhythmias, Cardiac; Kidney; Leucovorin; Liver; Male; Maximum Tolerated Dose; Methotrexate; Rats; Rats, Wistar; Survival Rate

Cardiotoxicity related to the widely used cytotoxic compound 5-fluorouracil (5-FU) is rare compared with the frequency observed with the use of anthracyclines. More effective protocols incorporating active biomodulatory compounds like folinic acid (FA) or combination chemotherapy change type and severity of toxicity as well. The objective of the current study was to assess cardiotoxicity of the combination 5-FU and folinic acid.. The authors' multicenter experience with 390 patients treated for advanced gastrointestinal cancer with intermediate-dose folinic acid and 5-FU was reviewed.. The overall risk of cardiotoxicity was 3%, which is not significantly higher than that reported with 5-FU alone. Eight of 53 patients with a history of cardiac disease reported cardiac symptoms (15.1%), compared with 5 of 337 patients (1.5%) with a no history of cardiac disease. Median time to symptoms was 3 days (range, 2-6). Nine patients had symptoms resembling myocardial ischemia, one patient died due to assumed myocardial infarction related closely to fluorouracil treatment, four patients had supraventricular arrhythmia, and one patient had congestive heart failure. A history of cardiac disease was the only risk factor associated with cardiotoxicity. Relapses were frequent on reinstitution of therapy despite cardiac symptoms in the preceding cycle. Therapeutically or prophylactically administered nitrates had no significant effect.. Physicians should be aware of the cardiotoxic properties of active fluorouracil treatment. The combination of 5-FU and leucovorin does not differ from single-agent therapy in frequency or type of cardiotoxicity. Close monitoring of patients is mandatory, especially for those patients at high risk for cardiac side effects. Treatment should be discontinued if coronary symptoms develop, because neither effective treatment nor prophylaxis exists for such symptoms.

Topics: Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Arrhythmias, Cardiac; Coronary Disease; Electrocardiography; Female; Fluorouracil; Gastrointestinal Neoplasms; Heart Diseases; Heart Failure; Humans; Leucovorin; Male; Middle Aged; Myocardial Infarction