January 5, 2016 - Wiggers

Question 1

Wigger’s Diagram

Answer 1

Question 2

What Part?

Answer 2

Mitral valve closes

Question 3

What Part?

Answer 3

Aortic valve opens

Question 4

Venous Waveforms

Answer 4

A wave - atrial contraction

C wave - closure of the valve

V wave - atrial filling during ventricular contraction

Question 5

Biphasic Pattern

Answer 5

The A-wave and the V-wave generate 2 “up-beats” for every heartbeat.

Question 6

Ventricular Filling

Answer 6

80% is passive, before atrial contraction

20% is atrial “kick”

Question 7

Atrial “Kick”

Answer 7

Normally, atrial contraction contributes 20% to ventricular filling.

In diseased states, the atrial contraction often contributes much more than 20%.

Loss of atrial contraction (like in atrial fibrillation) can result in significant reductions of ventricular filling in diseased states, but usually not in normal states.

Question 8

Stroke Volume Formula

Answer 8

SV = EDV - ESV

Question 9

Heart Sounds

Answer 9

First sound (S1) is the mitral valve closing and the aortic valve opening.

Second sound (S2) is the aortic valve closing and the mitral valave opening.

Sometimes get S3 and S4 in diseased states.

Question 10

S3 and S4

Answer 10

S3 occurs in early diastole. This is caused by rapid “overfilling” of the ventricle, usually occuring in heart failure.

S4 occurs in late diastole. This is caused by atrial contraction plus a stiff ventricle.

Question 11

Pressure Volume Loop

Answer 11

4-1 is ventricular filling

1-2 is mitral valve closing and aortic valve opening (contraction)

2-3 is ejection

3-4 is aortic valve closing and mitral valave opening (relaxation)

P x V is work. The area inside the lines is work.