1. Chapter 25 Assessment of Cardiovascular Function

2. Overview of Anatomy and Physiology
Three layers: endocardium, myocardium, epicardium
Four chambers: Right atrium and ventricle, left atrium and ventricle
Atrioventricular valves: tricuspid and mitral
Semilunar valves: aortic and pulmonic
Coronary arteries
Cardiac conduction system (electrophysiology)
Cardiac hemodynamics

3. Anatomy of the Heart
Figure 25-1

4. Cardiac Conduction System: Electrophysiology
(60-100)
(40-60)
(30-40)
(30-40)
Figure 25-3

5. Which of the following is the primary pacemaker for the myocardium?
Question
Which of the following is the primary pacemaker for the myocardium?
Atrioventricular junction
Bundle of His
Purkinje fibers
Sinoatrial node

6. Answer Sinoatrial node
Rationale: The sinoatrial node is the primary pacemaker for the myocardium.

7. Cardiac Action Potential
Depolarization: electrical activation of cell caused by influx of sodium into cell while potassium exits cell
Repolarization: return of cell to resting state caused by reentry of potassium into cell while sodium exits

8. Cardiac Action Potential (cont’d)
Refractory periods
Effective refractory period: phase in which cells are incapable of depolarizing
Relative refractory period: phase in which cells require stronger-than-normal stimulus to depolarize

9. Cardiac Action Potential Cycle
Figure 25-4

10. Greater Vessels, Heart Chambers and Pressures
Figure 25-2

11. Cardiac Hemodynamics
Stroke volume(SV): amount of blood ejected with each heartbeat
Preload: degree of stretch of cardiac muscle fibers at end of diastole
Afterload: resistance to ejection of blood from ventricle
Contractility: ability of cardiac muscle to shorten in response to electrical impulse

12. Cardiac Hemodynamics (cont’d)
Ejection fraction: percent of end diastolic volume ejected with each heart beat (left ventricle)
Cardiac utput (CO): amount of blood pumped by ventricle in liters per minute.
CO = SV × HR

13. Influencing Factors Control of heart rate
Autonomic nervous system, baroreceptors
Control of stroke volume
Preload: Frank-Starling Law
Afterload: affected by systemic vascular resistance, pulmonary vascular resistance

14. Contractility
Contractility increased by catecholamines, SNS, some medications
Decreased by hypoxemia, acidosis, some medications

15. Which of the following best defines stroke volume?
Question
Which of the following best defines stroke volume?
The amount of blood ejected with each heartbeat
Amount of blood pumped by the ventricle in liters per minute
Degree of stretch of the cardiac muscle fibers at the end of diastole
Ability of the cardiac muscle to shorten in response to an electrical impulse

16. The amount of blood ejected with each heartbeat
Answer
The amount of blood ejected with each heartbeat
Rationale: Stroke volume is the amount of blood ejected with each heartbeat. Cardiac output is the amount of blood pumped by the ventricle in liters per minute. Preload is the degree of stretch of the cardiac muscle fibers at the end of diastole. Contractility is the ability of the cardiac muscle to shorten in response to an electrical impulse.

17. Health History Demographic information Family/genetic history
Cultural/social factors
Risk factors
Modifiable
Nonmodifiable

18. Most Common Clinical Manifestations
Chest pain
Dyspnea
Peripheral edema, weight gain
Fatigue
Dizziness, syncope, changes in level of consciousness

19. Where does the nurse auscultate the apex of the heart?
Question
Where does the nurse auscultate the apex of the heart?
Erb’s point
Fifth intercostal space
Pulmonic area
Tricuspid area

20. Fifth intercostal space
Answer
Fifth intercostal space
Rationale: The nurse auscultates the apex of the heart at the left fifth intercostal space at the midclavicular line.

21. Assessment Physical examination Palpation, percussion, auscultation
Medications
Nutrition
Elimination
Activity, exercise
Sleep, rest

22. Assessment (cont’d) Vital signs Self-perception, self-concept
Roles, relationships
Sexuality, reproduction
Coping, stress tolerance
Prevention strategies
Family history

23. Health Promotion, Perception, and Management Questions
Ask regarding health promotion, preventive practices
What type of health issues do you have? Are you able to identify any family history or behaviors that put you at risk of this health problem?
What are your risk factors for heart disease? What do you do to stay healthy?
How is your health? Have you noticed any changes?

24. Health Promotion, Perception, and Management Questions (cont’d)
Ask regarding health promotion, preventive practices
Do you have a cardiologist or primary health care provider? How often do you go for checkups?
Do you use tobacco or alcohol?
What medications do you take?

25. Laboratory Tests Cardiac biomarkers CK, CK-MB Myoglobin
Troponin T and I
Lipid profile
Brain (B-type) natriuretic peptide
C-reactive protein
Homocysteine
Refer to Table 25-4

26. Electrocardiography 12-lead ECG
Continuous monitoring: hardwire, telemetry
Signal-averaged ECG
Continuous ambulatory monitoring
Transtelephonic monitoring
Wireless mobile monitoring

27. Electrocardiography (cont’d)
Cardiac stress testing
Exercise stress testing
Pharmacologic stress testing
Echocardiography
Transthoracic
Transesophageal

28. Diagnostic Tests Radionuclide imaging Myocardial perfusion imaging
Test of ventricular function, wall motion
Computed tomography
Positron emission tomography
Magnetic resonance angiography

29. Cardiac Catherization
Invasive procedure study used to measure cardiac chamber pressures, assess patency of coronary arteries
Requires ECG, hemodynamic monitoring; emergency equipment must be available
Assessment prior to test; allergies, blood work

30. Cardiac Catherization (cont’d)
Assessment of patient postprocedure; circulation, potential for bleeding, potential for dysrhythmias
Activity restrictions
Patient education pre- and postprocedure

31. Hemodynamic Monitoring
CVP
Pulmonary artery pressure
Intra-arterial BP monitoring

32. Phlebostatic Level
Figure 25-10

33. Pulmonary Artery Catheter and Pressure Monitoring System
Figure 25-12