If the ECG shows a downward shift of the ST segment, this condition is indicative of myocardial ischemia. In addition, in addition to ST-segment shift, T-wave inversion and even T-wave hypoplasia are all signs of insufficient myocardial blood supply due to coronary artery stenosis. If this occurs, other tests are needed to clarify the diagnosis, such as cardiac ultrasound, which can clarify the velocity and amplitude of motion of the ventricular wall. Coronary CTA and coronary angiography can clarify the extent of the narrowed lumen of the coronary artery. If the stenosis is greater than 70%, it can be treated by stenting. If the degree of stenosis is less than 70%, it can be treated conservatively with drugs, such as aspirin and isosorbide mononitrate dispersible tablets.