ORCID:0000-0002-0855-7079
Background
According to the 2018 Global Cancer Statistics provided by the International Agency for Research on Cancer, the number of new cancer cases were 18.1 million and 9.6 million death cases global in 2018【1】. Colorectal cancer was one of the most common malignant tumors in the world, accounting for 10% of all malignant tumors, which ranks the third in the malignant tumors. In China, colorectal cancer was the fourth third leading cause of cancer-associated mortality in men and the third in women【2,3】. With the continuous progress and maturity of radiotherapy and chemotherapy technology, the survival rate of patients has improved through the application of anti-tumor drugs alone or combined with radiotherapy. However, with the development of chemotherapy, anthracycline was introduced into the field of tumor therapy in 1960s, people have come to realize the cardiotoxicity caused by chemotherapy for the first time. With the development of medical technology, cardiotoxicity caused by anti-tumor drugs was gradually familiar and valued by experts of various disciplines. It was recognized that chemotherapy induced cardiotoxicity restrict the long-term survival of patients to a certain extent, and increased the global public health burden. In high-risk patients, prevention of heart failure caused by chemotherapy was crucial to their long-term health. This would not only increase their risk of cardiovascular disease and death, but also may limit their ability to receive adequate cancer treatment. Therefore, early detection of chemotherapy induced cardiotoxicity was very important.
Cardiooncology was an emerging field that aimed to optimize cancer treatment options and manage heart disease caused by cancer treatment. In the past decade, cancer therapy has been greatly developed, including many targeted therapies based on tumor genetics and receptor characteristics【4】. However, these were accompanied by a series of cardiovascular complications, including heart failure and left ventricular systolic dysfunction, myocarditis, arrhythmia, coronary artery, pericardial and valvular heart disease. More and more cardiac imaging technology, accompanied by ever-increasing technological developments, was applied to the diagnosis of diseases, such as speckle tracking echocardiography, PET-CT cardiac magnetic resonance and so on. But the best imaging method or biomarker to diagnose chemotherapy induced cardiotoxicity was still controversial.
The 5-fluorouracil and bevacizumab were widely used in the treatment of colorectal cancer【5】, but the early monitoring method of the structure and function of heart injury caused by this combination of the drugs was not perfect. This study used different monitoring methods to compare the changes of cardiac structure and function before and after the combination of bevacizumab and 5-fluorouracil injection in mice model. The purpose of this study was to explore a safe and effective detection method with strong clinical operability, which is in order to find an early detection of clinical chemotherapy induced cardiotoxicity.