User Progress Listen and Learn Take the Test Status & Table of Contents Heart Sounds Drill User Report Demo Mode Sign-in for progress tracking. Lesson TitleCompleted?ScoreHeart Sound Rhythm Third Heart Sound Split Second Heart SoundTrue 100%Split 2nd vs.unsplit 2nd & 3rd Physiologically Split 2nd Heart Sound Third and Fourth Heart Sounds Split First Heart Sound Split S1 and S4 Split First and Second Heart Sounds Third and fourth heart sounds Table of Contents Heart Sound Rhythm Third Heart Sound Split Second Heart Sound Split 2nd vs.unsplit 2nd & 3rd Physiologically Split 2nd Heart Sound Third and Fourth Heart Sounds Split First Heart Sound Split S1 and S4 Split First and Second Heart Sounds Third and fourth heart sounds Systolic murmur vs. diastolic murmur Early systolic vs. late systolic murmur Diamond vs. rectangular pan-systolic murmurs Early diastolic decrescendo vs. late diastolic crescendo murmur Third heart sound vs. mid-systolic click