Endothelial biomarkers are gaining interest in the stratification of cardiovascular risk and early diagnosis of cardiotoxicity secondary to antineoplastic drugs. Interestingly, some drugs, such as anthracyclines, have been recently associated with vascular damage, which reveals the pivotal role of research in identifying biomarkers that could potentially be included into more specific cardiotoxicity risk scores. An extensive report of the incidences of cardiovascular adverse effects of oncologic drugs is presented, with the main purpose of highlighting not only the risk of developing heart failure but also the importance of associated vascular adverse effects (i.e., hypertension, venous, and arterial thrombosis) experienced by patients in the post-chemotherapy phase.