Extra Heart Sounds (S3 and S4) Third and Fourth Heart Sound Gallop 25 Listen The patient's position should be supine. Description Both the third and fourth heart sounds (S3 and S4) are low frequency. S4 is lower than S3. This is a pattern that occurs with improvement of heart failure. That is, an S3 pattern gives way to an S3 S4 pattern as the patient improves. Visualize Observe LessonsThird Heart Sound Gallop.Fourth Heart Sound Gallop.✓Third and Fourth Heart Sound Gallop.Summation Gallop at 120 beats per minute.Sign-in to enable progress reports and certificates.