Cardiotoxicity is one of the undesirable effects that limit the use of anthracyclines, such as doxorubicin, as part of the CHOP regimen, which is caused by the formation of complexes between ferric ions and the anthracycline within the myocyte. Because of their oxidative properties, these complexes are toxic and produce highly reactive free radicals that damage the lipid membrane and lead to the cell death of myocytes. Several studies have linked the onset of cardiotoxicity with old age, high cumulative doses of doxorubicin, cardiovascular risk factors and previous heart disease, among others. Anthracycline-induced cardiotoxicity is cumulative and irreversible. Moreover, left ventricular dysfunction is an important late effect in patients with aggressive NHL who survive long term and, according to some studies, have received doxorubicin at doses higher than 200 mg/m². Cardiotoxicity may be silent or subclinical, which is usually detected as a decrease in left ventricular ejection fraction (LVEF), or clinical, with varying degrees of congestive heart failure (CHF). Depending on the symptoms, cardiotoxicity also differs between acute, subacute, late or chronic. The first is manifested at an early stage, usually as arrhythmia, transient ECG changes or pericarditis, among others, is usually reversible, is not detrimental to the continuation of treatment and is not associated with subacute and late toxicity.