Auscultation of Common Abnormal Heart Sounds

Auscultation of Common Abnormal Heart Sounds

Listen to Heart Sounds Here!

http://depts.washington.edu/physdx/heart/demo.html

Murmurs:

Grading

• Grade I – Heard in a quiet room by an expert examiner
• Grade II – Heard by most examiners
• Grade III – Loud murmur without thrill
• Grade IV – Loud murmur with a thrill
• Grade V – Thrill with a very loud murmur audible with stethoscope placed lightly over the chest
• Grade VI – Thrill with a very loud murmur audible even with the stethoscope slightly away from the chest

Aortic Stenosis

• heard best at the right upper sternal border
• radiates to the carotid arteries
• sounds like a harsh, high-pitched systolic crescendo-decrescendo murmur (while the ventricles are contracting)
• normal S1 and narrow split or normal S2 (due to delayed aortic valve closure)

Mitral Regurgitation

• heard best at the apex of the heart (4th-5th left intercostal space, midclavicular)
• radiates to the axilla and/or the base of the heart
• sounds like a blowing, high-pitched holosystolic murmur that stays the same throughout (plateau; blood moves backward across the mitral valve as the ventricles contract)
• muffled S1 and widely split S2

Extra Heart Sounds:

S3

• if coming from the left ventricle, heard best at the apex with the patient in the left lateral decubitus position (lying on his/her left side) while holding breath at the end of expiration
• if coming from the right ventricle, heard best at the left lower sternal border or the xiphoid while the patient is supine
• heard best with the bell of the stethoscope
• sounds like a low-pitched beat in early diastole (while the ventricles are filling with blood from the atria)
• may be due to excess blood moving from the atria into the ventricles (volume overload) or a stiff ventricle (overfilled and/or hypertrophied ventricle)
• can be normal in those who are younger than 40 years old; if > 40 years old, check for enlarged ventricle(s)
• differentiate from normal splitting of heart sounds, which are HIGH-PITCHED and heard best with the DIAPHRAGM of the stethoscope

S4

• if coming from the left ventricle, heard best at the apex with the patient in the left lateral decubitus position (lying on his/her left side) while holding breath at the end of expiration
• if coming from the right ventricle, heard best at the left lower sternal border or the xiphoid while the patient is supine
• heard best with the bell of the stethoscope
• sounds like a low-intensity beat late in diastole
• may be due to decreased compliance of ventricle (as in S3) or forceful contraction of atria (“atrial kick”)
• will not be heard if atrial fibrillation or atrial flutter present
• differentiate from normal splitting of heart sounds, which are HIGH-PITCHED and heard best with the DIAPHRAGM of the stethoscope

Source (to learn more about heart sounds):

Mangla, A. (2014, April 24). Heart sounds. Medscape. Retrieved from http://emedicine.medscape.com/article/1894036-overview