АннотацияВ настоящее время онкологические заболевания являются одной из основных причин смертности. Современная противоопухолевая терапия позволяет сохранять жизнь и социальную адаптацию онкологических пациентов в течение многих лет. Однако применение противоопухолевых препаратов ограничено из-за их побочных, в ряде случаев тяжелых кардиотоксических эффектов, таких как ишемическая болезнь сердца (ИБС), токсическая кардиомиопатия, хроническая сердечная недостаточность (ХСН), артериальная гипертензия и др. Нарушения ритма и проводимости встречаются в среднем у 16-36% пациентов, получающих химиопрепараты, а фибрилляция предсердий (ФП) является одним из наиболее частых аритмогенных проявлений кардиотоксичности. Антрациклины, алкилирующие агенты и моноклональные антитела нарушают работу ионных насосов, способствуют избыточному выходу кальция из саркоплазматического ретикулума, изменению потенциала действия, более быстрому развитию спонтанной диастолической деполяризации и в конечном итоге провоцируют развитие ФП. Некоторые химиопрепараты, в частности антрациклины, ингибиторы тирозинкиназ и гистон деацетилазы, нарушают работу калиевых каналов, что приводит к увеличению потенциала действия и удлинению интервала QT. Данные о влиянии других классов химиопрепаратов на проводящую систему сердца немногочисленны и противоречивы. Нарушения ритма и проводимости, вызванные химиотерапией, могут привести к снижению дозы или отмене противоопухолевых препаратов, требуют тщательного мониторирования и совместного подхода врачей нескольких специальностей к ведению этих пациентов. Ключевые слова:кардиотоксичность, фибрилляция предсердий, синдром удлиненного интервала QT, антрациклины, моноклональные антитела, ингибиторы тирозинкиназ. Конфликт интересов:авторы заявляют об отсутствии конфликта интересов. Прозрачность финансовой деятельности:никто из авторов не имеет финансовой заинтересованности в представленных материалах или методах. Для цитирования: Васюк Ю.А., Шупенина Е.Ю., Новосел Е.О., Агапов И.С. Нарушения ритма и проводимости сердца как проявления кардиотоксичности противоопухолевого лечения -миф или реальность? Сибирский медицинский журнал. 2020;35(1):13-21. https://doi. AbstractOncologic diseases are currently one of the leading causes of death. Modern anticancer therapy allows preserving life and social adaptation of cancer patients for many years. However, the use of anticancer drugs is limited due to their adverse and, 13-21 + Elena Y. Shupenina,

Cancer is the second leading cause of mortality in the world, second only to cardiovascular diseases. Simultaneously cancer mortality has been steadily decreasing due to the development  of new chemotherapy and targeted  drugs  and the improvement  of existing  treatment protocols.  Improving the prognosis of treatment of cancer patients leads to an unexpected  result - more patients are faced with side effects of cancer treatment. Cardiotoxicity, including  arrhythmia, has  become  a significant  factor  to reduce  the effectiveness  of cancer  patient’s  treatment.  Atrial  fibrillation  is frequent  and persistent a rhythm disorder, affecting  all categories  of patients, especially the elderly. An association  between these two conditions  can be expected, considering the fact that in old age the prevalence of malignant neoplasms  and comorbid pathology predisposing to the onset of AF is high. Therefore, AF may be an additional  factor negatively  influencing the prognosis and treatment tactics in patients with malignant neoplasms. A comprehensive search was conducted  using the keywords  “cancer”, “atrial fibrillation” and “cardiotoxicity” using the PubMed,  Scopus and Cohrane  databases. We reviewed publications having the relationship between AF and cancer. The literature review considered 61 publications on the prevalence of AF in cancer patients, classification, mechanisms of development, the effect of anticancer drugs and other treatment methods on this group of patients. Analyzed articles include clinical guidelines, consensus  expert opinions,  systematic  reviews,  meta-analyzes, and previously  published  reviews of the literature. The problem of cardiotoxic  complications diagnostics is evaluated separately,  incl. arrhythmias, and their monitoring in cancer patients. Therefore, the direction of medicine named "Cardio-oncology" comes to the fore. Interdisciplinary interaction will allow identify cardiotoxic  manifestations at the subclinical stage and optimize anticancer treatment.

Introduction. Cancer remains one of the most common causes of death in the world, second only to cardiovascular diseases. The use of novel chemotherapeutic and targeted agents has significantly improved the prognosis of this group of patients. However, this significantly increased the number of cardiotoxic complications of anticancer therapy, including arrhythmias, in particular atrial fibrillation (AF), which negatively affects the prognosis.Brief description. The purpose of this article was to describe the case of a 64-yearold woman with central right lung lower lobe cancer. Upon admission to the chemotherapy department, the patient was first diagnosed with paroxysmal AF. After chemical cardioversion, the first course of multiagent chemotherapy (MAC) was performed as follows: paclitaxel 280 mg and carboplatin 450 mg, which was complicated by the development of recurrent AF episode. During subsequent MAC courses, arrhythmia episodes regularly occurred. During the next AF episode, the patient was hospitalized at the City Clinical Hospital № 51, where she died despite intensive therapy. Postmortem examination ruled out tumor invasion into the left atrium.Discussion. For the AF development, the patient had prerequisites in the form of a significantly remodeled left atrial myocardium. Chemotherapy agents used as antitumor therapy are characterized by the common development of cardiotoxicity, including variety of arrhythmias. The occurrence of AF episodes coincided with the course of MAC, which suggested its cardiotoxic manifestations. Postmortem examination confirmed the high probability of an association between AF episodes and MAC.Conclusion. The presented case illustrates the difficulties encountered by oncologists and cardiologists in determining the genesis and treatment of complex arrhythmias in cancer patients.

Aim. To search early signs of cardiotoxicity in patients receiving anticancer therapy and evaluate the effectiveness of cardioprotection with an angiotensin-converting enzyme inhibitor, beta-blocker and myocardial cytoprotector.Material and methods. The study included 98 patients with high and very high risk of cardiotoxicity according to the Mayo Clinic scale (USA). Cancer patients with hypertension were offered cardioprotective treatment with a fixed-dose combination of perindopril and bisoprolol, and patients with very high risk and concomitant coronary artery disease additionally trimetazidine.The patients were divided into 2 following groups: the experimental group (n=50), where patients were prescribed cardioprotective therapy, and the control group (n=48), which consisted of patients who refused or had contraindications to cardioprotection. All patients underwent an examination, including the collection of complaints and anamnesis, physical examination, electrocardiography and echocardiography with an assessment of left ventricular (LV) global longitudinal strain before chemotherapy and 1, 3, 6, 9 and 12 months after initiation of anticancer therapy.Results. In patients of the control group, by the end of the follow-up, the left atrial volume index and LV end-diastolic volume index significantly increased. In the main group, these indicators did not change significantly. In the control group, by the final visit, the LV ejection fraction significantly decreased in comparison with the initial value and the value in the first group. After 6, 9 and 12 months, there was a significant decrease in the LV global longitudinal strain in the control group, while in the main group this indicator remained within the normal range. The mortality rate in the control group was significantly higher (15% vs 2% in the experimental group). In the experimental group, cardiotoxic complications occurred in 28%, while in the control group — in 78% of patients.Conclusion. The study demonstrated the significant importance of cardiac monitoring and primary drug prevention of cardiotoxicity of anticancer therapy. A sig nificant deterioration in LV systolic function was shown in patients with a high and very high risk of cardiotoxicity who did not receive cardioprotective therapy, while its high efficiency was demonstrated in patients of the experimental group.

Cardiovascular and oncological diseases are the leading causes of adult death in the world. Despite proven efficacy, anticancer drugs can cause severe cardiovascular complications. Recently, data have appeared on the possible vasotoxic effects of chemotherapy drugs, which can manifest themselves as the progression of arterial hypertension and atherosclerosis, the development of myocardial ischemia and acute coronary syndrome, the formation of venous and arterial thrombosis. The key mechanism for the development of vasotoxicity is endothelial dysfunction, and anticancer drugs can also affect the processes of thrombosis. The review presents the results of 12 selected observational retro- and prospective studies involving cancer patients receiving presumably vasotoxic therapy. Data on the frequency of occurrence and possibilities for the prevention of vasotoxicity are presented.