Extra Heart Sounds (S3 and S4)

Summation Gallop at 120 beats per minute

At a heart rate of 120 beats per minute, the diastolic period is shortened. This causes the third and fourth sound to be superimposed, creating a single loud sound. The anatomy video shows an enlarged left ventricle with decreased left ventricular contractility and a minimally enlarged left atrium.

Listen

patient torso with stethoscope chestpiece

The patient's position should be supine.

Visualize

Observe

The cardiac animation shows an enlarged left ventricle with decreased left ventricular contractility and a minimally enlarged left atrium.