Heller Ch. 3

Question 1

P wave

Answer 1

Atrial depolarization

Question 2

QRS complex

Answer 2

Ventricular depolarization

Question 3

T wave

Answer 3

Ventricular repolarization

Question 4

Aortic pressure

Answer 4

Diastole: 80mmHg
Systole: 120mmHg

Question 5

Left ventricular volume

Answer 5

End-Systole: 60mL

End-Diastole: 120mL

Question 6

Right atrial pressure

Answer 6

A wave: contraction
C wave: tricuspid valve ballooning
V wave: Isovolumetric filling

Question 7

Pulmonary artery pressure

Answer 7

Diastole: 10mmHg
Systole: 25mmHg

Question 8

Valve changes

Answer 8

Valve placement is determined by pressure

Question 9

Sounds

Answer 9

Caused by valve closure (AV valves or aortic/pulmonic)

Question 10

Incisura (dicrotic notch)

Answer 10

Dip in aortic pressure caused by a small volume of blood filling the aortic leaflets as the valve closes

Question 11

S1 sound

Answer 11

Closure of AV valves
Immediately after QRS complex
Heard best at the apex

Question 12

S2 sound

Answer 12

Closure of aortic/pulmonic valves
At the end of T wave
Physiological splitting of the second heart sound–the pulmonic valve will lag behind the aortic (particularly with inspiration)

Question 13

S3 sound

Answer 13

Does NOT usually happen
Happens shortly after S2…called ventricular gallop rhythm
During rapid passive ventricular filling
Can be normal in children…otherwise indicates left ventricle failure

Question 14

S4 sound

Answer 14

Does NOT usually happen
Happens shortly before S1…called atrial gallop rhythm
Associated with atrial contraction and rapid active filling of the ventricle
Indicates an increased ventricular diastolic stiffness…can occur with several cardiac disease states

Question 15

Left ventricle cycle

Answer 15

Mitral valve opens-->
Diastolic filling (passive stretch)-->
Reaches end-diastolic volume (length)-->
Isovolumetric contraction (Isometric tension development)-->
Aortic valve opens-->
Ejection (shortening)-->
Reaches end-systolic volume (length)-->
Isovolumetric relaxation (Isometric relaxation)

Question 16

Cardiac index

Answer 16

Cardiac output corrected for the individual’s size…more by surface area than weight

Question 17

Larger end-diastolic volume

Answer 17

Larger stroke volume

Peak isometric tension initially increases slower than resting tension

Question 18

Larger afterload (HTN or aortic valve obstruction)

Answer 18

Smaller stroke volume

There is less shortening

Question 19

Myocardial substrate use during basal metabolism

Answer 19

25%

Question 20

Myocardial substrate use during isovolumetric contraction

Answer 20

50%
Depends on afterload
Related more to isometric wall tension development than to intraventricular pressure development

Question 21

Stroke work

Answer 21

Pressure x volume

Pressure work adds up more than volume work

Question 22

Heart Rates effect on substrate consumption

Answer 22

One of most important determinants

It is better energetically to have a lower HR and an higher SV than the opposite

Question 23

Lusitropic

Answer 23

Relaxation rate

Question 24

5 effects of NE

Answer 24

Positive chronotropic effect (increases i[f])
Decreases duration (earlier i[K])
Positive dromotropic effect (alters conductivity of gap-junctions)
Positive inotropic effect (activates i[Ca++])
Positive lusitropic effect (increases SR reuptake of Ca++)