Neoplasia is the main cause of general death in the Brazilian population. In 2016, they were responsible for approximately 211,343 (16%) deaths, followed by cardiovascular diseases (12.6%). Despite the high mortality rate of neoplasia, oncological treatment have advanced substantially in recent decades improving the prognosis of patients. However, growing evidence suggest that some oncological agents may induce significant toxicity that may play a major role in the quality of life, morbidity and mortality. The cardiovascular system is often negatively affected with cancer therapy, predisposing several patients to stop appropriate treatments or to have cardiovascular events related to the cardiotoxicity. The most typical manifestation of cardiotoxicity and related consequences (heart failure) are related to the use of anthracyclines. Anthracyclines are part of the chemotherapy regimen for solid tumors and hematological neoplasms in children and adults, and are associated with an increase in life expectancy. Carvedilol is an α and β-blocker that also has antioxidant properties. Preliminary studies have shown that carvedilol and its metabolites prevent lipid peroxidation, inhibit the formation and inactivate free radicals, in addition to preventing the depletion of endogenous antioxidants, such as vitamin E. These effects would potentially prevent anthracycline injury but definitive evidence is still needed. This is a multi-center, double-blind, randomized, placebo-controlled study that aims to establish the efficacy of carvedilol for the primary prevention of left ventricular systolic dysfunction in cancer patients obtained with anthracycline chemotherapy, in different schedules and doses.

Inclusion Criteria:

• ≥18 years of age at the time of screening
• Cancer patients that will receive chemotherapy with anthracyclines.

Exclusion Criteria:

• Inability to adequate asses left ventricular function
• Previous symptoms (dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea, and pulmonary and systemic congestion) suggestive of or a previous diagnosis of heart failure.
• Previous history of any cardiomyopathy (eg.: valve disease, Chagas' disease, infiltrative cardiomyopathy)
• LVEF < 50%
• Previous history of myocardial revascularization
• Permanent tachyarrhythmia (flutter, atrial fibrillation, atrial tachycardia)
• Congenital heart disease with left ventricular function impared
• Contra-indication to the use of beta-blockers.
• Pregnant or Breast-feeding females or women of childbearing age who intend to became pregnant.
• On kidney replacement therapy
• ECOG >= 4 or Karnofsky <=30
• Advanced hepatic failure (C score Child-Pugh and MELD > 15);
• Previous use of anthracycline
• Have any serious concomitant systemic disease, condition, or disorder that, in the opinion of the investigator, should preclude participation in this study
• Are concurrently enrolled in any other type of medical research judged not to be scientifically or medically compatible with this study

Randomization will be in the proportion of 1: 1 (carvedilol x placebo). Both randomization and allocation of patients will be chosen in a veiled manner to patients and to assess. Data on randomization and allocation will be under custody of the Data analysis and safety committee.