The video shows a close-up of a human heart, which is red in color, with a blue line moving across it. The blue line is a graphical representation of an electrocardiogram (ECG) line, which is a measurement of the heart's electrical activity. The ECG line moves across the heart in a wave-like pattern, indicating the heart's rhythm. The background of the video is a plain, light pink color, which provides a clear contrast to the red heart and blue ECG line.