HEART SOUNDS by Don Hudson, D.O., FACEP/ACOEP
Everything You need to Know About Heart Sounds • We have all heard the heart make the usual sounds. LUB----------DUB • Lub is the first sound or S1 • Dub is the second heart sound or S2
So What is All of The Other Sounds • The best way to understand the individual sounds is to think about what is causing them • First you need to concentrate on the total sounds and then try to listen to the individual component sounds
Systole • The time between the S1 and S2 sounds is: Lub------------Dub • The ventricles contracting • Blood flowing from the heart to the lungs and body • Blood flowing across the Pulmonic and Aortic valves
DiastoleDub----------Lub The time between S2 and S1 is : • The blood is flowing from the atria to the ventricles. • The blood flowing across the bicuspid and tricuspid valves. • The atrial contraction also occurs now.
S1- What is it ? The “lub” in the lub – dub. • This sound is primarily because of the closing of the bicuspid and tricuspid valves. • Anatomically they are located between the atria and the ventricles • They close because the ventricles contract • The Pulmonic and Aortic valves are opening and blood is being forced into the arteries
S2- What is it ? S2 is the “dub” in the lub- dub • The sounds are because of the closing of the Pulmonic and Aortic valves as the pressure from the arteries is greater then the pressure in the ventricles. • This is the end of systole
What Kinds of Sounds Do You Hear? • Murmurs-usually indicate turbulence & they range from 1 to 5 in loudness. • Does it occur during diastole or systole? • Does it crescendo (get progressively louder)? • Does it decrescendo (get progressively quieter)? • Where do you hear it best? (Neck, Chest, Axilla)
Other Sounds • Gallops- these are either S3 or S4 sounds. • Rubs- pericardial or plural friction rubs and usually indicated either pericarditis or possible pleurisy ( must be careful to listen to both heart and lung sounds) • Rubs- sounds “sandpapery”
Other Sounds • Clicks- only occur in systole and represent the loud valve closing • Diastolic Knock- occurs because of a abrupt arrest of ventricular filling by a non-compliant & constricting pericardium. • Continuous Murmurs- indicate a constant shunt flow throughout systole & diastole i.e. Coarctation, or patent ductus arteriosus.
Anatomy of A Sound • LUB-- DUB-------------LUB--DUB • S1 S2 S3 S4 S1 S2 • Here is where you expect to hear the various sounds
Now that you Hear the Sounds (what does it mean?) First Heart Sound (S1) • - Louder than usual - Mitral Stenosis • - Variable Atrial Fib./Complete Heart Block • -Diminished Mitral or Aortic Regurg.
Second Heart Sounds (S2)(what does it mean) Wide split sounds or fixed ( not moving with respiration) may indicate: • Atrial Septal Defect • RBBB • Pulmonic Stenosis
Extra Heart Sounds (S3 & S4)(what do they mean to you) • Third Heart Sound (S3) Markedly Diminished Left Ventricular Function • (Almost always present with Myocardial Ischemia or early after an AMI) • Fourth Heart Sound (S4) Modestly Diminished Left Ventricular Function
What Special Things Do You Need To Hear These Sounds • Stethoscope • As quite an environment as possible • Proper positioning of the patient • Stethoscope must touch the skin • Patient history • Ability to observe the chest, abdomen & neck
Where Do You Listen? • Left Ventricle Area- The apex of the heart is at the 4th or 5th intercostal space (ICS) along the midclavicular line (MCL). • Right Ventricular Area- the 3rd to 5th ICS along the left sternal border (LSB) • Pulmonic Area- 2end ICS along LSB • Aortic Area- 2end ICS along the right sternal border (RSB)
Stethoscope Use • The diaphragm of your stethoscope is most useful for picking up high-pitched sounds i.e. S1, S2, Aortic or Mitral Regurgitation Murmurs or Friction Rubs. • The Bell is most useful for picking up low-pitched sounds, S3, S4, or Mitral Stenosis.
Thank You For Your Patience Practice, Practice, Practice Patience to take time to listen Time to listen to history Expose the patient Think Reflect Your patients will appreciate your efforts