Chapter 17 Review

Question 1

Clinical Focus 17.3
What is VSD?

Answer 1

VSD is ventricular septum defect
-Causes blood to flow freely between both chambers

Question 2

Left-to right shunt in VSD is caused by?
Right to left shunt is caused by?

Answer 2

A greater pressure of the left ventricle to right. (oxygenated blood mixes w deoxy and into circulation)

Large VSD the allows right (deoxy) to mix with left(oxy)

Question 3

Which shunt causes systemic arterial hypoxemia?

Answer 3

Right to left shunt

Question 4

Explain cardiac electrical conduction

Answer 4

1.Electrical impulses originate in the SA node
2-Intranodal bundles-
3. AV node-AV bundles of His-
4.left and right branches of Av bundles of His-
5. purkenje fibers

Question 5

Clinical focus 17.6
What the preferred biomarkers for diagnosing myocardial infarction (MI)?

Answer 5

TNL, TNT

Question 6

Which coronary artery is dominate supplier of heart?

Answer 6

Right coronary artery

Question 7

What is the Frank-Sterling mechanism?

Answer 7

The heart’s inherent ability to increase force of contraction according to venous return
(venous return affects cardia output)

Question 8

Left anterior descending and circumflex artery supplies which part of heart?

Answer 8

Anterior and lateral portion of left ventricle

Question 9

Veins contain what percent of blood volume?

Answer 9

64 percent

Question 10

What determines right atrium pressure?

Answer 10

Blood flow from vena cavas (venous return)

Question 11

Map equation

Answer 11

Map=(syst+2dyst)/3

Question 12

What is characteristic pain in chest called?

Answer 12

Angina pectoris

Question 13

In acute MI, blood levels increase within how many hours?

Answer 13

3-12 hours

Question 14

What is blood flow in ml at rest?

Answer 14

225 ml per min or 4-5% of CO

Question 15

Most coronary perfusion happens when ?

Answer 15

At rest

Question 16

How long do electrical impulses travel from SA node to AV node?
SA node to ventricles?

Answer 16

-0.03 sec
-0.16 sec

Question 17

Sympathetic beta 1 has what effect on myocardial force?

Answer 17

Increases

Question 18

Where can point of maximal impact be felt?

Answer 18

5th intercostal space and midclavicular line

Question 19

What is the end diastolic volume of each ventricle?

Answer 19

110-120 ml

Question 20

Each ventricle ejects how much blood?

Answer 20

70 ml

Question 21

What is normal ejection fraction?
Less than _signifies what?

Answer 21

-60%
-50%, poor contractility and pumping failure

Question 22

Increased HR has what effect on CO?

Answer 22

Increases up to 170-220
above this range signifies inadequate dyst

Question 23

Main cardiac sympathetic receptors?

Answer 23

Beta 1

Question 24

What determines mean arterial pressure (MAP)?

Answer 24

-Stroke volume
-Arterial compliance
-Arterial resistance

Question 25

What is hypertensive MAP at rest?

Answer 25

110

Question 26

What is renin?

Answer 26

an enzyme produces by RAAS, acts on a plasma protein to produce angiotensin I.

Question 27

renin–angiotensin–aldosterone system (RAAS)

Answer 27

produces renin enzyme

Question 28

What is release of B-type natriuretic peptide (BNP) response to?

Answer 28

High blood pressure and stretch of ventricular walls ;
BNP inhibits the RAAS; it is an aldosterone antagonist.

Question 29

angiotensin-converting enzyme (ACE)

Answer 29

converts angiotensin I to angiotensin II.

Question 30

What effect does left ventricular failure have on wedge pressure?

Answer 30

Increases

Question 31

SVR formula

Answer 31

svr= (map-cvp)/CO x 80

Question 32

Pvr formula

Answer 32

pvr= (mpap-pcwp)/ CO x 80

Question 33

Bonus Q