Clinical Analysis Of The Acute Radiation-Induced Heart Disease

Objective：To explore the correlation of electrocardiogram, serumcardiac troponin I (cTnI), myocardial enzyme, cardiac functionindicators, clinical and physical factors with the acute radiation-inducedheart disease (RIHD)in patients with thoracic tumor.Methods:51patients of thoracic tumor with first processradiotherapy from November2011to December2012were included inthis study.25patients were lung cancer (24cases were central type,1casewas peripheral type) and26patients were esophagus cancer (5cases inthe upper segment of chest,13cases in the middle and8cases in thelower).49cases were confirmed by pathology and2cases of patientswere diagnosed as lung cancer according to clinical symptoms andimaging examination. All patients were received intensity modulatedradiotherapy (IMRT). The prescription dose of PTV of patients withesophagus caner was50~63Gy (median dose60Gy), The prescriptiondose of PTV of patients with lung cancer was46.8~66Gy (median dose58Gy), Radiation was delivered at1.8～2.1Gy/times/day, five times perweek, a total of26~33times. All patients were examined byelectrocardiogram, myocardial enzyme, serum cTnI and color dopplerechocardiography before, after and3months after radiotherapy, NCICTCAE-3.0evaluation standard was used to evaluate acuteradiation-induced heart disease. To explore the correlation ofelectrocardiogram, serum cTnI, myocardial enzyme, the cardiac functionindicators, clinical (including gender, age, history of hypertension,chemotherapy, KPS scores, TNM staging,) and physical (including themaximum dose of heart, the mean dose of heart, the minimum dose ofheart, Heart DVH parameters from heartD100to heartD5and heartV5to heartV60) factors with the acute radiation-induced heart disease inpatients with thoracic tumor.Results: There were37cases of patients occurred acute RIHD in thewhole group. The total incidence rate was72.55%(37/51).34cases werethe grade1,2cases were the grade2,1case was the grade3, none abovegrade3of acute RIHD were found.1Electrocardiogram changes with acute RIHDThere were21cases of patients with abnormal electrocardiogramincluding6cases with sinus tachycardia,6cases with premature atrialcontraction or ventricular premature contraction,4cases with elevated STsegments and T waves variation,2cases with left or right bundle branchblock,2cases with left ventricular high voltage, one case with sinusbradycardia. In all of the patients whose electrocardiogram wereabnormal,17cases were abnormal after radiotherapy, Of which8casesreturned to normal three months later,9cases were still abnormal (3cases with sinus tachycardia,1case with premature atrial contraction,1case with elevated ST segments and T waves variation,1case with leftbundle branch block,1case with sinus bradycardia,2cases with leftventricular high voltage),4cases occurred abnormal electrocardiogramthree months after radiotherapy (2cases with sinus tachycardia,2caseswith premature atrial contraction).2Myocardial enzyme spectrum, serum cTnI with acute RIHDThere were11cases elevated with myocardial enzymes and5withtroponin I. Comparing serum AST, CK, CK-MB, LDH and HBDHbefore, after and3month after radiotherapy, it was showed that the levelof serum AST, CK were decreased after radiation therapy and increased3months after radiotherapy (P <0.05). The level of serum CK-MB werelower both after and3months after radiotherapy than before radiotherapy.The levels of Serum LDH, HBDH have no statistical significant before,after and3months after radiotherapy. The level of serum cTnI after radiotherapy was higher than before radiotherapy, while it was lower3months after radiotherapy (F=3.468, P=3.468).3Cardiac function with acute RIHDThere were26cases with left ventricular systolic function reduced,8cases with left ventricular diastolic function reduced and3cases withpericardial effusion. Comparing cardiac function indicators before, afterand3months after radiotherapy, Left ventricular ejection fraction (EF),shortening fraction (FS) and E/A value had statistical significance (P <0.05). EF was decreased both after and3months after radiotherapy, FSand E/A value were decreased after radiotherapy, while3months afterradiotherapy were increased.4Physical and clinical factors with acute RIHDPhysical factors of the groups with and without acute RIHD have nostatistical differences (P>0.05). Clinical factors of the groups with andwithout acute RIDH have no statistical differences (P>0.05). Throughunivariate analysis of physical and clinical factors, we have not found thesignificant influence factors of acute RIHD.Conclusions：Electrocardiogram abnormalities were common inacute RIHD, which mainly included sinus tachycardia and proiosystole,part of the abnormal electrocardiogram caused by radiotherapy werereversible. The level of serum AST, CK and cTnI were elevated afterradiotherapy, of which cTnI was more sensitive. It was showed that leftventricular contraction and diastole function were reduced afterradiotherapy. We have not found heart DVH parameters and clinicalfactors were correlated with acute RIHD.