A 39-year-old man complains of shortness of breath and squeezing pain behind his chest calm. 10 days ago he had the flu. Objectively established: outside forced - sitting, leaning the torso forward, the face is swollen, cyanotic, swollen jugular veins. The boundaries of the heart are significant extended in both directions, deaf tones, rhythmic, heart rate - 104/min., respiratory rate - 28/min. The ECG revealed: decreased voltage of the teeth, concordant ST segment changes. On the radiograph: a spherical shadow of the heart, signs of stagnation in the lungs. IN blood revealed: erythrocyte sedimentation rate - 38 mm/h. What is the probable diagnosis?