Examination Features (Med Secrets p59)

Question 1

Explain normal splitting of the second heart sound

Answer 1

S2 normally split into Aortic (A2) and pulmonary (P2). Degree of splitting varies with respiratory cycle

Question 2

How does inspiration affect splitting of the second heart sound?

Answer 2

With inspiration, negative intrathoracic pressure INC venous return to RA and DEC to LHS. Thus:

• P2 occurs slightly later
• A2 to occur slightly earlier

Question 3

How does expiration affect splitting of the second heart sound?

Answer 3

Negative intrathoracic pressure is eliminated and A2 and P2 occur almost simultaneously

Question 4

What is paradoxical S2 splitting?

Answer 4

Widening with expiration and shortening with inspiration (opposite of normal)

Question 5

Causes of paradoxical S2 splitting?

Answer 5

• Aortic insufficiency
• Aortic stenosis
• Hypertrophic cardiomyopathy
  Generally conditions that delay A2 by delaying ejection of blood from the LV

Question 6

What is the significance of a loud P2?

Answer 6

Usually indicated pulmonary HTN

Question 7

What is S3?

Answer 7

Low frequency heart sound just after S2; also called ventricular gallop

Question 8

How is S3 best heard?

Answer 8

With bell. Does not change with respiration

Question 9

What is a pathologic S3?

Answer 9

S3 occurring in a variety of pathologic conditions including:

• CHF
• mitral valve prolapse
• thyrotoxicosis
• coronary artery disease
• cardiomyopathies
• pericardial constriction
• mitral or aortic insufficiency

Question 10

What is the mechanism behind S3?

Answer 10

Controversial: may be due to increase in the blood entering the ventricle (rapid ventricular filling). Usually indicates ventricular decompensation associated with heart disease.

Question 11

What is S4?

Answer 11

Sound occurring just before S1. Reflects decreased ventricular compliance (stiff ventricle).

Question 12

What is an opening snap?

Answer 12

High frequency early diastolic sound associated with mitral or tricuspid valve opening.

Question 13

What causes a pericardial knock?

Answer 13

Sudden slowing of LV filling in early diastole associated with the restriction of a rigid pericardium acting as a “rigid shell” such as in chronic constrictive pericarditis

Question 14

What are the physical examination findings in MR?

Answer 14

• Apical holosystolic murmur
• S3
• Quick upstroke and short duration of peripheral pulses
• Widened pulse pressure
• Hyperdynamic praecordium

Question 15

What are the 3 waves composing the JVP?

Answer 15

• A wave: produced by RA contraction, occurring just before S1
• C wave: caused by bulging upward of the close tricuspid valve during RV contraction
• V wave: caused by RA filling just before opening of the tricuspid valve

Question 16

What are cannon A waves?

Answer 16

Very large and prominent A waves occurring when the atria contract against a closed tricuspid valve.

Question 17

Define pulsus paradoxus

Answer 17

Drop of more than 10mmHg in sBP during normal inspiration

Question 18

Why does pulsus paradoxus occur?

Answer 18

• Fall in intrathoracic pressure during inspiration rapidly transmitted through pericardial effusion = exaggerated inc in venous return to R heart.
• Inc return to R causes septal bulging to L
• Smaller LV volume