As a result of advances in screening, diagnosis and treatment methods in modern oncology, survival rates of patients with malignant neoplasms have considerably improved. Among the most promising therapeutic trends, emphasis is on the new immunotherapy method with T-cells expressing chimeric antigen receptors (CAR-T). CAR-T cell therapy is most commonly used in oncohematology. However, despite the efficacy of new therapeutic methods, also CAR-T cell therapy, more and more evidence on side effects becomes available. One of the most common complications (in about 1/3 of all cases) is cardiovascular toxicity (CVT) with high mortality. This accounts for an actively developing new interdisciplinary field of research called cardio-oncology that studies cardiovascular complications of chemotherapy and the methods of their monitoring and prevention. This review covers currently known pathophysiologic mechanisms of CVT on CAR-T cell therapy. Additionally, it discusses clinical manifestations, prevention strategy, and programs for monitoring cardiovascular adverse events reported by hematologists.