When angina is not attacked, the ECG examination is usually normal, but it does not mean that there is no heart disease, at this time, the diagnosis can be clarified through relevant examinations, the examination methods are as follows: 1, dynamic ECG examination: to capture the dynamic changes in the ECG during the attack to help the diagnosis; 2, cardiac ultrasound examination: to clarify the presence of abnormal ventricular wall motion; 3, coronary angiography or coronary artery enhancement CT examination: to clarify the presence of Vascular lesions, clarify the presence of coronary artery vascular stenosis; 4, activity plate exercise test: can increase the heart load, clarify the electrocardiogram with or without myocardial ischemia performance, to help determine the presence of coronary heart disease. So in the usual activities if there is chest suffocation, chest pain symptoms, you need to go to the hospital in time to further clarify the diagnosis to prevent malignant events.