A 56-year-old scientist experiences constricting retrosternal pain several times a day while walking for 100-150 m. The pain lasts for up to 10 minutes and can be relieved by nitroglycerine. Objectively: the patient is overweight, heart borders exhibit no abnormalities, heart sounds are rhythmic, Ps- 78 bpm, AP- 130/80 mm Hg. ECG contains low amplitude of T wave in V4-5. What disease might be suspected?