LP #105 Dysfunction As A Fxn Of Lost Structural Or Functional Integrity

Question 1

• Checks heart fxn
• measures cardiac cycle rhythm (electrical activity)
• Predictable & repeated pattern of waves

Answer 1

(ECG) Electrocardiography tracings

Question 2

Reading ECG tracings (P wave)

Answer 2

• 1st wave, small amplitude

- depolarization wave from SA node to atria

Question 3

Reading ECG tracings (QRS complex)

Answer 3

• small dip (Q) to large peak (R) to larger dip (S)

- d/t ventricular depolarization & precedes ventricular contraction

Question 4

Reading ECG tracings (T wave)

Answer 4

• 3rd wave, small amplitude

- ventricular repolarization

Question 5

• abn rate of heart contractions
• d/t problems w/intrinsic conduction
• leads to uncoordinated myocardial contractions
• affects circulation
• may occur in healthy or diseased hearts
• may cause tachycardia or bradycardia

Answer 5

Cardiac arrhythmia

Question 6

• Excessive rapid heart rate
• decrease blood filing heart (diastole)= decrease blood pumped out (systole)
• requires increase O2 & nutrients but needs not met d/t decrease blood filling heart in diastole
• leads to decrease coronary circulation (ischemia)

Answer 6

Tachycardia

Question 7

• excessive flow heart rate

- causes impaired BF & ischemia to vital organs

Answer 7

Bradycardia

Question 8

• rapid irregular contractions of the myocardium= poor blood pumping
• life threatening (defibrillation)

Answer 8

Fibrillation

Question 9

Disruptions in AP initiation or signal conduction=

Answer 9

Cardiac dysfxn

Question 10

• excitable focus outside a faulty SA node

- assumes control of HR

Answer 10

Ectopic pacemakers

Question 11

• occurs w/damaged nn

- impulses are unable to move across damaged section d/t scar tissue

Answer 11

Heart conduction block

Question 12

-medical replacement of defective intrinsic pacemakers

Answer 12

Artificial pacemakers

Question 13

Causes of cardiac arrhythmia & conduction block

Answer 13

• congenital defects
• degenerative changes
• ischemia & myocardial infractions
• fluid & electrolyte imbalances

Question 14

• P changes in hearts chambers open/closes vavles (depends on structural integrity)
• structural integrity is lost d/t scar tissue build up on valves & chordae tendinae

Answer 14

Valvular defects

Question 15

Causes of valvular defects

Answer 15

• congenital
• ischemia
• inflammation & fibrosis

Question 16

2 general types of valvular defects

Answer 16

• stenosis

- incompetent valves

Question 17

• narrowing of opening b/w:
• atrium & ventricle, or ventricle & bv’s
• d/t fibrosis
• leads to stiff valves
• difficult for valves to open/close
• leads to restricted bl flow

Answer 17

Stenosis

Question 18

Stenosis is often d/t

Answer 18

Chronic rheumatic fever (debilitating)

Question 19

• narrowing of opening b/w L ventral & aorta

* leads to restricted blood ejection into aorta

Answer 19

Aortic valve stenosis

Question 20

Aortic valve stenosis results in

Answer 20

• L ventricle enlargement- becomes weakened
• decrease SV & BP
• poor effusion of coronary aa

Question 21

Aortic valve stenosis often d/t

Answer 21

• rheumatic fever (endocarditis)

- congenital heart defects

Question 22

S/s aortic valve stenosis

Answer 22

• dyspnea
• vertigo
• angina pectorals

Question 23

• narrowing of opening b/w L atrium & ventricle

* leads to resistance to BF & decrease SV

Answer 23

Mitral valve stenosis

Question 24

Mitral valve stenosis causes

Answer 24

• increase P in left atrium

- leads to pulmonary congestion & increase BP d/t backup of blood in pulmonary vv

Question 25

S/s mitral valve stenosis

Answer 25

- nocturnal dyspnea & orthopnea - atrial tachycardia & fibrillation - palpitations, angina pectoris, weakness & fatigue - heart murmurs

Question 26

* d/t valve distortion, valves don’t close properly & cause back flow into affected chamber * back flow increase chamber P - leads to dilation of heart chamber * all heart valves are susceptible * most often affected: aortic & mitral valves

Answer 26

Incompetent (regurgitant) valves

Question 27

S/s aortic valve regurgitation

Answer 27

- dyspnea on exertion - pulmonary edema - angina pectoris - orthopnea - decrease ability for strenuous physical Activity

Question 28

* blood backs up from aorta to L ventricle: - L ventricle hypertrophies d/t increase BVol - some blood remains in ventricle - systemic BP difficult to maintain - decrease blood entering aorta= decrease P in bv’

Answer 28

Aortic valve regurgitation

Question 29

* causes back flow of blood from L ventricle into L atrium | - blood leaks into L atrium during L ventricle systole

Answer 29

Mitral valve regurgitation

Question 30

S/s mitral valve regurgitation

Answer 30

- increase BVol & P in L atrium - increase BP in pulmonary vv - enlarged L atrium - rapid atrial fibrillation (leads to ABN & turbulent BF) - clots may form in L atrium - an embolus may be pumped out of heart & cause blocked aa

Question 31

Israel valve regurgitation may be asymptomatic for ___ to ___ years as ventricle is initially able to:

Answer 31

* 10-20 years - maintain sufficient output - maintain adequate BP & circulation

Question 32

* present at birth, indicates - disease - detrimental intrauterine events - fetal exposure to a maternal condition

Answer 32

Congenital heart defects

Question 33

S/s associated w/ congenital heart defects

Answer 33

- altered heart fxn - heart failure - pulmonary disorders - tissue ischemia

Question 34

Sx’s include: congenital heart defect

Answer 34

- interrupted growth of heart structures - displaced positioning of chambers or bv’s - altered closure of fetal cardiac-lung shunts