While killing tumor cells, antitumor drugs also cause damage to normal tissues and organs, especially the toxic reaction to the heart, which often leads to the death of patients not from tumors but from cardiac complications, and the cardiotoxicity of antitumor drugs has become the “heart disease” of oncologists. This is mainly due to the difficulty of oncologists in dealing with cardiac problems, while cardiologists in general hospitals seldom come into contact with patients with cardiac complications due to antitumor therapy. This is an area of concern to all, but one that none can penetrate deeply enough. Currently, many of the large clinical trials of antineoplastic drugs take a mostly simplistic approach in regards to cardiotoxicity. There are many antitumor drugs in common use in clinical practice, and the mechanism of cardiotoxicity varies, and there is no reliable test method for determining cardiotoxicity. Although the clinical manifestations of cardiotoxicity of antineoplastic drugs are diverse, heart failure (HF) poses the greatest threat to patients. The onset of HF due to antitumor drugs is insidious, but once it occurs, the prognosis is very poor and the mortality rate is high. Therefore, early detection and treatment of HF is particularly important. Early prediction by combining several index indicators Left ventricular ejection fraction Previous monitoring methods mainly measured left ventricular ejection fraction (LVEF), which is not truly representative of the incidence of cardiotoxicity due to the fact that a large number of cardiomyocytes have been damaged by the time of the LVEF decline, not to mention an indicator of early diagnosis. It has been found that HF with preserved LVEF (i.e., HF with normal LVEF) accounts for 20% to 50% of all HF, and even 27% of patients with acute left heart failure have LVEF ≥50%. Thus, LVEF is a less sensitive indicator. Troponin I and B-type natriuretic peptide Probably the most promising tests for early prediction of cardiotoxicity are troponin I (TNI) and B-type natriuretic peptide (BNP). TNI is the serum marker with the highest specificity for myocardial injury and is also the most sensitive. It has a sensitivity of 97%, a specificity of 98%, and a positive predictive value of 99.8%. TNI is abnormal when >1 g of myocardium is injured. However, if chronic or cumulative myocardial damage occurs, the TNI may have little or no change, thus failing to truly and dynamically reflect cardiac toxicity, and is only a marker reflecting real-time acute myocardial damage. BNP has a close relationship with HF and can reflect the dynamic changes in cardiac function and its degree, with high sensitivity and specificity in diagnosing HF. It is found that if >100 pg/ml is taken as the standard, its sensitivity in diagnosing HF reaches 90% and specificity reaches 76%, and the level of BNP is positively correlated with cardiac function, which can be used as an indicator for dynamic observation of changes in cardiac function, and therefore can also be used as an indicator for determining the clinical efficacy and prognosis. However, BNP also has a shortcoming, i.e., its level is positively correlated with the change of LV wall tension. If HF is severe but chronic, and therefore the change of LV wall tension is small or unchanged, the correlation between the level of BNP and HF may be decreased. In summary, until a sensitive method for diagnosing cardiotoxicity is found, LVEF, TNI and BNP should be analyzed in combination with history, clinical examination and other ancillary tests, such as electrocardiograms and chest X-rays. Finding better treatments and drugs For patients at high risk of antitumor drug cardiotoxicity or those who have already experienced cardiotoxicity, the treatment effect is not ideal according to the current cardiology HF and other relevant guidelines, which may be related to the fact that the damage to the myocardium caused by antitumor drugs is different from that caused by the myocardial damage mechanism of general cardiac diseases. Finding better treatments and drugs becomes the key to solving the problem. Research on cardiomyocyte protectors Cardiomyocyte protectors may hold the promise of treating cardiotoxicity of antitumor drugs. At present, there are not many studies in this area, although some results have been achieved, but most of them are the results of the application of general heart disease, the effect of cardiotoxicity against antitumor drugs is still uncertain, and how to apply, whether it is used singly or in combination, etc., need for further research. Fructose 1,6 diphosphate is an important intermediate product of cellular energy metabolism, which can play a significant cardiomyoprotective role by improving cellular energy metabolism, stabilizing cell membranes to inhibit inflammation, inhibiting oxygen free radicals, reducing intracellular inorganic phosphorus and extracellular free calcium concentrations, positive inotropic effect and antagonizing doxorubicin-induced apoptosis of cardiomyocytes, among other mechanisms. Trimetazidine improves myocardial energy metabolism and protects cardiomyocytes by increasing the level of adenosine triphosphate and decreasing the concentration of adenosine diphosphate and adenosine monophosphate. This drug has been widely used in ischemic cardiomyopathy and protection of myocardial injury after cardiac interventional therapy, and has achieved good results. Levocanidin is a naturally occurring energy metabolizing substance in the body, which has been mostly used in the supplemental treatment of hemodialysis patients. Now it is found that the drug has the ability to promote lipid metabolism, improve myocardial energy supply, increase tissue tolerance to ischemia and hypoxia, and so on, and can achieve the role of protecting cardiomyocytes. It is currently used with good results in the treatment of HF. Creatine phosphate is a high-energy phosphoric acid compound, which can directly enter into cardiomyocytes to increase the energy supply of cardiomyocytes, and also has the effect of increasing the stability of phospholipid bilayer, inhibiting the peroxidation of cardiomyocytes, promoting the inward flow of calcium to improve the contractile function of the myocardium, inhibiting the aggregation of platelets, and so on, and has now been widely used in the treatment of myocarditis, cardiomyopathy, HF, coronary heart disease, and so on. Research on myocardial protection against antitumor drugs Total flavonoids Its main components, quercetin and naringenin, can inhibit zorubicin-induced apoptosis of H9c2 cardiomyocytes, and researchers believe that flavonoids may be beneficial in regulating or preventing the cardiotoxicity of zorubicin. Carbon monoxide (CO) and bilirubin inhibited doxorubicin-induced apoptosis in H9c2 cardiomyocytes, which in turn may ameliorate doxorubicin-induced cardiomyocytotoxic damage. Erythropoietin Inhibits doxorubicin-induced apoptosis in rat ventricular cardiomyocytes in a dose-dependent manner. Plant Phenolics Plant phenolics such as apigenin, baicalein, kaempferol, lignocerol, quercetin, coffee, chlorogenic acid, and rosemary are known to attenuate cardiac membrane, mitochondrial, and microparticle damage in lactating rat cardiomyocytes and iron-dependent doxorubicin-induced lipid peroxidation. L-carnitine blocks doxorubicin-induced cardiomyocyte damage by inhibiting ceramide production. Unfortunately, research in this area is still limited to the laboratory stage, with no results from clinical trials, and there appears to be a long way to go. Relevant studies in the field of traditional Chinese medicine Finally, we will talk about the research in the field of cardiomyocyte protection in the motherland medicine. Ginseng and wheat injection The active ingredient is mainly ginseng saponin, and the test found that after its pretreatment, the reperfusion injury of rats was significantly reduced, presenting a good cardiomyocyte protection effect, as well as cardiotonic and antihypertensive effects. Astragalus The main component is astragalus saponin, which has enhanced and regulated immunity, regulated cytokine secretion and good free radical scavenging effect, and then achieve myocardial cell protective effect. Other Chinese medicines that may have cardioprotective effects include Paeonia lactiflora, Polygonum multiflorum, Taraxacum officinale, Angelica sinensis, Rhizoma Ligustici Sinensis, Pueraria Mirifica, Tanshinone IIA sulfonic acid sodium, etc., as well as a number of compound preparations. Conclusion In conclusion, there is no sensitive detection method for the cardiotoxicity of antitumor drugs, and cardiotoxicity is mainly manifested as HF, but there is a lack of effective treatment. Therefore, at this stage, the comprehensive evaluation of cardiotoxicity and the monitoring of high-risk patients using various indexes such as LVEF, TNI and BNP may be a better choice, and cardiomyocyte protectors may be the hope for the treatment and prevention of cardiotoxicity. We hope that through extensive collaboration between oncologists and cardiologists, in-depth clinical observation, accumulation of data, mapping the occurrence of cardiotoxicity of antitumor drugs in China, formulating a treatment plan for the actual condition, and carrying out randomized controlled clinical studies under the guidance of biostatisticians and in accordance with the principles of the GCP, in order to summarize the proven treatment methods supported by evidence.