Subclinical left ventricular dysfunction is the most common cardiac complication after chemotherapy administration. Detection and early treatment are major issues for better cardiac outcomes in this cancer population. The most common definition of cardiotoxicity is a 10-percentage point decrease of left ventricular ejection fraction (LVEF) to a value <53%. The myocardial injury induced by chemotherapies is probably a continuum starting with cardiac biomarkers increase before the occurence of a structural myocardial deformation leading to a LVEF decline. An individualised risk profile (depending on age, cardiovascular risk factors, type of chemotherapy, baseline troponin, baseline global longitudinal strain and baseline LVEF) has to be determined before starting chemotherapy to consider cardioprotective treatment. To date, there is no proof of a systematic cardioprotective treatment (angiotensin-converting enzyme inhibitor and/or betablocker) in all cancer patients. However, early cardioprotective treatment in case of subclinical left ventricular dysfunction seems to be promising in the prevention of cardiac events.