Monitoring The Effect Of Low Dose Anthracycline Chemotherapy On Myocardial Damage By Echocardiography

BackgroundBreast cancer is a common and life threatening malignant tumor which serious impact on women's health.Recent years,the incidence of breast cancer is increasing,anthracycline based chemotherapy combined with other chemotherapy drugs is the first-line treatment for adjuvant chemotherapy in patients with breast cancer.With the progress of anti-tumor therapy,the survival of patients with breast cancer was significantly prolonged,anthracycline cardiotoxicity is an important factor affecting the survival and mortality,seriously affect the prognosis of patients.Echocardiography is a common cardiac toxicity monitoring method,with noninvasive,convenient,economical,good reproducibility and other advantages,but the traditional ultrasound indexes-left ventricular ejection fraction(LVEF)due to poor sensitivity,the variation of less than 10%,and affected by the heart load,not suitable for detecting the early changes in cardiac function.Anthracycline dosage is relatively low in the treatment of breast cancer in China.Monitoring of low dose anthracycline chemotherapy for cardiac toxicity requires a more sensitive monitoring method.Two dimensional speckle tracking technique is a new technique developed in recent years.It can obtain myocardial longitudinal strain,radial strain,circumferential strain,layered myocardial strain,myocardial segments' strain,rotation and torsion parameters at the same time.Two dimensional strain parameters,especially the left ventricular longitudinal strain,have been shown to precede decrease in LVEF during anthracycline chemotherapy and after the end of chemotherapy.ASE/EACVI and ESC guidelines both strongly recommend a GLS-based follow up during the course of chemotherapy.However,the value of left ventricular layered myocardial strain,myocardial segments' strain and left atrial strain is not clear in monitoring the myocardial damage during low dose anthracycline chemotherapy in Chinese population.This research evaluates the effect of low dose anthracycline chemotherapy on cardiac structure and function in patients with breast cancer with both routine echocardiographic parameters and two-dimensional strain parameters.Objectives1.To evaluate the effects of anthracycline cardiotoxicity with two dimensional speckle tracking imaging,and compared with conventional echocardiographic parameters,and discuss the value of two-dimensional speckle tracking in early detection of anthracycline-related cardiotoxicity.2.The find out the correlation between the cumulative dose of anthracycline with the index of cardiac fuction and the correlations between other routine echocardiographic parameters.Methods1.Study population 40 patients breast cancer patients who were hospitalized from March 2017 toMarch 2018,all women,aged 27-64 years and average age 47.27±9.9.The chemotherapy regimen based on anthracycline was used.All patients were examined by echocardiography at baseline before chemotherapy(TO)and after the second(T2),fourth(T4),and sixth(T6)chemotherapy cycle.Inclusion criteria:age 18-70 years old;confirmed by histopathology in our hospital,first diagnosed with breast cancer and without malignant tumor history;the expected life period more than 6 months;had not been previously accepted chemotherapy and(or)radiotherapy;KPS ?80;blood routine test,liver and kidney function and electrocardiogram was normal;good compliance,voluntarily accept the research regulations.Exclusion criteria:heart failure,myocardial infarction,persistent atrial fibrillation,myocarditis,cardiomyopathy,severe valvular diseases and other patients with severe heart disease;patients accepted chemotherapy and adjuvant radiotherapy at the same time,women in pregnancy or lactation period;echocardiography image quality is poor,unable to obtain clear images.2.EquipmentPHYLIPS EPIQ7C with S5-1 probe(1.0-1.5Hz)is used for the research.QLAB10.8 workstation is used for data analysis.3.ExaminationThe patient's name,age,height,weight,heart rate,blood pressure,fasting blood glucose,serum lipid level,medical history and other general clinical data were collected.Connection with ECG at the same time,stored at least 3 consecutive cycles of dynamic image of left ventricular parasternal long axis,AP4,AP2,AP3 and the left ventricular apex,papillary muscle level,mitral valve level short axis view in DICOM format,stored in the mobile hard disk for offline analysis.4.Imaging processing and data analysisMeasure LA,AO,RVAW,RVD,LVEDd,LVPW,IVS,RAD-T,RAD-L,RVD-B,RVD-M,RVD-L,FAC.We use biplane Simpson's method to measure LVEDV,LVESV,LVEF,LAV and calculate LAVI.We use M echocardiography to measure TAPSE.We use pulsed doppler echocardiography to measure E,A,DT,and calculate E/A.We use tissue doppler echocardiography to measure e'(s)?e'(1),S',and calculate e,,E/e'.We use 2D-STI to measure GLS,GCS,GLS-Mid,GLS-Epi,RVGLS,LAGLS,SD respectively,we measure Prot-A,Prot-B,and calculate PTW.we also measure GLS in every views and every segments.5.Statistical analysisSPSS20.0 software was used for statistical analysis.All data are expressed as means ± standard deviation.Compared the datas between different two groups using the paired t test.Pearson correlation analysis was used in the correlation analysis of continuous data.The data were both tested by bilateral test,and P<0.05 indicated that the difference was statistically significant.ResultsThe study collected 40 breast cancer patients who were treated by anthracycline chemotherapy,all women,average age 47.27±9.9,10 patients with hypertension,8 patients combined with dexrazoxane in chemotherapy process.1.Conventional echocardiography parameters comparisonCompared with the baseline values before chemotherapy,there are no significant changes in the diameters of the heart in the course of chemotherapy,the left ventricular systolic function index LVEF value in T4 and T6 is significantly decreased(P<0.01);left ventricular diastolic function parameters e' is significantly decreased in T6,right ventricular systolic function indexes FAC,TAPSE,S' in the course of chemotherapy is not significant changed(P>0.05),but with the increase of the cumulative dose of anthracyclines,the value of these parameters are all decreased.2.2D-STI parameters comparisonGLS,GLS-Mid,GLS-Epi,GLS-AP4,GLS-AP3 are all decreased significantly compared with the baseline value before the chemotherapy,and the GLS-AP2 is significantly decreased in T4(P<0.05).Compared with T0,left ventricular segmental strain value,the apical interval(AS)is significantly reduced in T2(P<0.01),apical anterior wall(AA)and the basal anterior wall(BA)decreased significantly at T4(P<0.05),the middle portion of the anterior wall(MA)and apical(Apex)is significantly reduced at T6(P<0.05).3.Correlation analysisAfter chemotherapy,the ?LVEF value and ?GLS are positive correlation(r=0.475,P<0.01),and the correlation between ?LVEF and left ventricular diastolic function index ?E/A is significantly(r=0.401,P<0.05);?TAPSE,?RVGLS also correlate positive to ?LVEF significantly(P<0.05).Conclusions1.The cardiotoxicity of anthracycline chemotherapy is mainly manifested by impaired left ventricular systolic function,and the cardiotoxicity can occur at low dose,the left ventricular systolic function is gradually decreased with the increase of cumulative dose.2.GLS is more sensitive to the cardiac toxicity of anthracycline than LVEF,and it can detect the subclinical myocardial injury more early.