Early Detection of Cardiac Damage by Two-Dimensional Speckle Tracking Echocardiography After Thoracic Radiation Therapy

Inclusion Criteria: * with malignant tumors * will receive radiotherapy * with cardiac exposure during the radiotherapy process * could receive regular follow-up for 12 months * written informed consent Exclusion Criteria: * satisfactory echocardiographic images could not be obtained * moderate or severe valvular disease * cardiomyopathy * congenital heart disease * refractory hypertension * coronary artery disease\* * heart failure * arrhythmia requiring intervention * pericarditis * acute myocarditis * participating in other clinical studies of drug intervention * severe liver and kidney dysfunction * autoimmune disease * pulmonary hypertension coronary artery disease: at least 50% stenosis besed on previous coronary angiography or CTA, or with a history of percutaneous coronary stent implantation. \*: with LVEF\<50%, unstable angina，or acute myocardial infarction within 3 months.