Essential Heart Sounds Reduced Intensity First and Second Heart Sounds Patients who are obese or have emphysema will often have diminished heart sounds. Hearing these greatly reduced intensity sounds can take practice. Listen The patient's position should be supine. Visualize Observe Authors and Reviewers Authored by Thomas O Brien. Medically reviewed by Dr. Jonathan Keroes, MD Last Update: 11/8/2021 LessonsNormal First and Second Heart Sounds - No Splitting✓Reduced Intensity First and Second Heart SoundsSplit Second Heart SoundThird Heart Sound (S3) GallopFourth Heart Sound (S4) GallopThird and Fourth Heart Sound GallopSummation Gallop at 120 beats per minuteFixed Splitting of Second Heart SoundMid-Systolic ClickSystolic Murmur - Aortic StenosisDiastolic Murmur - Aortic RegurgitationMitral Valve Leaflet ProlapsePansystolic Murmur - Mitral RegurgitationDiastolic Murmur - Mitral Stenosis Medically reviewed: William A. French