CV Heart Sounds

Question 1

What is a heart murmur?

Answer 1

A murmur is when a valve does not open or close properly during cardiac phases of systole or diastole, depending on the valve. In other words, blood does not functionally go where it is supposed to in heart chambers or vasculature.

Question 2

When will a murmur of a stenotic (stiff) valve be heard?

Answer 2

Heard when the valve should be OPENED.
Ex: Tricuspid or Mitral Valves during Diastole
OR
Aortic or Pulmonic Valves during Systole

Question 3

When will a murmur of an Insufficient (Regurgitant) Valve be heard?

Answer 3

When the valve is supposed to be CLOSED
Ex: Tricuspid or Mitral Valve during SYSTOLE
OR
Aortic or Pulmonic Valve during DIASTOLE

Question 4

When listening to heart sounds what pieces of advice can be given to a newbie?

Answer 4

1. Listen for murmurs DOWNSTREAM of blood flow.

2. Listen as INFERIORLY as possible if looking for heart sounds pertaining to specific chambers/valves

Question 5

What events occur during SYSTOLE (sounds, valves, blood flow)

Answer 5

1. S1 initiates Systole
2. AV valves are CLOSED (Tricuspid & Mitral); SL valves are OPEN
3. Blood flows from (R/L) ventricles to (pulmonic/systemic) circulation

Question 6

What events occur during DIASTOLE?

Answer 6

1. S2 initiates DIASTOLE
2. AV valves are OPENED; SL valves are CLOSED (*Aortic & Pulm)
3. Blood flows from the (R/L) atria to the (R/L) ventricles (filling)

Question 7

What is S3 Heart Sound produced by? What does it sound like? What are the causes and when does it occur?

Answer 7

Produced by Tight papillary muscles in EARLY DIASTOLE, as Rapid Ventricular Filling.
AKA “ventricular gallop”
Can be normal in young children
OR
Pathological in adults (indicating Heart failure, LVV Overload: Dilated ventricle)

Question 8

What is the S4 Heart Sound produced by? What are the causes?

Answer 8

Produced by Strong Atrial Contraction in the late diastole atrial contraction, from a Poorly compliant ventricle.
AKA “atrial gallop”; Always Pathologic
Causes: HTN, Aortic Stenosis, Pulmonary Stenosis, MI, Age *Always Pathological.

Question 9

Where does the mitral valve close on the ECG?

Answer 9

MV closes on the tip of R-wave, representing S1 (1st heart sound)

Question 10

Where does the end of Systole occur on the ECG?

Answer 10

S2, which marks the end of systole (closure of aortic valve) is heard on T-wave of ECG.
*During inspiration, S2 splits into A2 and P2

Question 11

Describe the events that cause P2 to shift right (splitting of S2).
*What are the pathologic causes?

Answer 11

1. Decreased intrathoracic pressure
2. Higher venous return where the right heart fills more
3. Increased capacitance of the Pulmonary Artery
4. Slight delay in Pulmonic valve closure (P2 comes later ->Right)
   * Right BBB, Pulmonary Stenosis, Pulm. HTN [Prolongs RV emptying]

Question 12

Describe the events that cause A2 to shift left (inspiration of S2)
*What are the pathologic causes?

Answer 12

1. Increased Capacitance of Pulmonary Vein (low flow)
2. Less EDV (less blood to pump)
3. Earlier Aortic Valve Closure
   * Left BBB, Aortic Stenosis [Prolongs LV emptying]

Question 13

Describe what occurs in the Wide Splitting of S2?

Answer 13

Right BBB or Pulmonic Stenosis causes P2 to close later and A2 to close earlier in Second Heart Sound.

Question 14

Describe what occurs in Paradoxical Splitting.

Answer 14

Left BBB - left bundle branch block; left side contracts later, so A2 occurs later than P2 within 2nd heart sound.