This review, based on the ESC Position Paper on cancer treatments and cardiovascular toxicity developed under the auspices of the ESC Committee for Practice published in 2016, the current publications by Russian and international experts, publications in MEDLINE, Medscape MedPulse, PubMed, PubMed Central, addresses the concept of timely diagnosis, treatment, and monitoring of cancer patients receiving chemoradiotherapy (CRT). The issues of early and late diagnosis of cardiovascular disorders and complications due to the cardiotoxic effect of CRT are considered. The features of clinical presentation and cardiotoxicity mechanisms of some anticancer drugs are presented. It has been shown that due to the specific mechanism of action, traditionally used chemotherapeutic agents and some of the novel anticancer signal inhibitors are associated with a significant risk of cardiovascular side effects, including cardiac dysfunction and heart failure, arterial hypertension, vasospastic and thromboembolic ischemia, arrhythmias and QT prolongation. Two side effects have been reported: irreversible, progressive heart failure and temporary cardiac dysfunction without apparent long-term sequelae for the patient. The objective of this review is to draw the attention of cardiologists to the cardiotoxicity issue, early markers of damage, clinical presentation, and features of the disease course, algorithms for early and late diagnosis of this condition. The tasks facing the cardiologist and oncologist in choosing a management strategy for early and long-term sequelae of CRT, depending on the clinical manifestations, are presented. Recommendations are given on using a targeted cardioprotective adjuvant in patients with diagnosed disorders. This article also reviews the mechanisms of action of mitochondrial metabolic cardioprotective agent phosphocreatine (Neoton), the drug of choice. The evidence of this drug’s beneficial clinical, functional, and morphological effects on the myocardial tissue damaged due to cardiotoxic effects was provided. It is noted that phosphocreatine infusions (Neoton) can be used as a targeted adjuvant cardioprotective therapy in complex anticancer CRT.