Clinical Study Of Radiation-induced Cardiac Injury In Patients With Thoracic Tumor Complicated With Metabolic Syndrome

Objective: To investigate the related factors of radiation-induced cardiac injury in patients with thoracic tumor complicated with metabolic syndrome.Through the clinical analysis and study of the occurrence of radiation heart injury after chest radiotherapy in this type of patients,to discuss the relationship between the occurrence of radioactive heart damage in patients with metabolic syndrome and their own factors and radiation physics parameters,to explore the clinical value of cardiac dose,symptoms,myocardial enzymology,electrocardiogram and echocardiography in predicting radioactive cardiac injury in patients with metabolic syndrome.Method: Patients who received chest radiotherapy in the Affiliated Hospital of Qingdao University from December 2018 to December 2019 were collected,and patients who met the diagnosis of metabolic syndrome were selected according to the Chinese Guidelines for the Prevention and Treatment of Type 2 Diabetes(2017 Edition)formulated by the Diabetes Branch of the Chinese Medical Association,A total of 41 patients were included.Collect patient case information,including: age,gender,tumor type,pathological type,clinical N staging,and whether to accept standardized metabolic syndrome treatment according to the specialist's order during radiotherapy(weight control,hypotension,Lipidlowering,hypoglycemic,etc.).All patients signed the informed consent form before radiotherapy.All patients received intensity-modulated radiation therapy,conventional segmentation irradiation: 1.8-2Gy one day,5 treatments from Monday to Friday,rest on weekends,and no concurrent chemotherapy during radiotherapy.Observe the patient's cardiac ultrasound before the start of radiotherapy,after the end of radiotherapy and 3 months after the start of radiotherapy(measure the left ventricular ejection fraction,ventricular diameter,atrial inner diameter,ventricular end-diastolic diameter,cardiac output to evaluate cardiac function,valve changes,etc.);ECG examination(whether arrhythmia,ST-T abnormality,long QT,ventricular tachycardia,etc.);myocardial enzyme test(lactate dehydrogenase,creatine kinase,creatine kinase isoenzyme);whether Symptoms of cardiac discomfort(precardiac discomfort,chest tightness,heart muscle,chest pain,etc.).Dose volume histogram(DVH)is used to calculate the corresponding physical parameters,including the ratio of PTV / heart volume.Dmean represents the average cardiac dose,and heart V5-V50 represents the percentage of the heart volume that received 5Gy-50 Gy to the total heart volume.Heart D5-D60 represents the radiation dose received by 5%-60% of the heart volume.The RTOG "Diagnostic Standard for Radiation Heart Injury" was used to evaluate the occurrence of radiation heart injury in patients.SPSS 22.0 statistical software was used for chi-square analysis,Mann-Whitney exact rank sum test,Logistic model multi-factor analysis,Spearman analysis and ROC curve for data analysis and statistical processing of clinical factors,cardiac examination results,physical parameters.Result: A total of 24 cases of 41 patients in the group had radiation heart injury,and the total incidence of radiation heart injury was 58.54%(24/41).All patients had Grade 1 and 2 radiation heart injury,and no Grade 3 or above acute radiation heart injury occurred.Chisquare test analysis showed that clinical N stage and whether to receive treatment were related to the occurrence of RIHD(P = 0.046,0.034,P <0.05);age,gender,pathological type,tumor classification and RIHD were not related(P > 0.05).Among them,the probability of radiation heart injury in the standard treatment group was 46.15%,and the probability of radiation heart injury in the non-standard treatment group was 80.00%.Mann-Whitney's exact rank sum test results of physical parameters showed that the difference between the occurrence of RIHD and non-occurrence of RIHD in heart V20-V45,average heart dose,heart volume,and PTV / heart volume ratio was statistically significant(P <0.05);And the heart V5,V10,V15,V50,V55,V60,the maximum heart dose,PTV Dmax,PTV volume are not factors influencing radiation heart injury(P> 0.05).The above-mentioned significant clinical factors and physical parameters were analyzed by a multi-factor retrospective of the Logistic model,and the results showed that: whether to receive standardized treatment,V30 and PTV / heart volume ratio are independent risk factors that affect the occurrence of heart injury(Wald = 4.806,4.179,3.885,P = 0.028,0.041,0.049).The receiver working curve confirmed that V30 can predict the occurrence of radiation heart injury with moderate accuracy.In addition,the chi-square test was used to analyze the symptoms of patients,electrocardiogram,and myocardial enzymes to predict RIHD.The results showed that symptoms and myocardial enzymes had no predictive effect on RIHD(P = 0.187,0.326,P>0.05);The ECG can effectively predict RIHD(P = 0.037,P <0.05).For the role of echocardiography in predicting RIHD,Spearman correlation analysis was used,and the results showed that E / A had the greatest correlation with RIHD(rs value = 0.669,P = 0.025).Conclusion: 1.When patients with their own metabolic syndrome are receiving chest radiotherapy,patients should be prescribed treatment according to the guidelines of endocrinologists according to the relevant guidelines of metabolic syndrome(hypertension,glucose,lipid lowering,etc.),which can effectively reduce the chest radiotherapy Radiation heart injury.2.V30 and PTV / heart volume ratio are independent risk factors that affect radiation heart injury in patients with metabolic syndrome.Patients with a large PTV / heart volume ratio are more prone to radiation heart injury.The dose limitation of V30 can effectively reduce the occurrence of radiation heart injury and predict the occurrence of radiation heart injury with moderate accuracy.3.When patients with metabolic syndrome receive chest radiotherapy,electrocardiogram can predict the occurrence of radiation heart injury,and the E / A ratio in cardiac ultrasound has the most correlation with the occurrence of radiation heart injury.Periodic review of ECG and echocardiography during chest radiotherapy has certain clinical significance.