1. (Relates to Chapter 32, “Nursing Assessment: Cardiovascular System,” in the textbook) Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc.

2.  Heart  Four chambers  Composed of three layers  Endocardium  Myocardium  Epicardium Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 2

3. Blood Flow Through the Heart Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 3 Fig. 32-1. Schematic representation of blood flow through the heart. Arrows indicate direction of flow. 1, The right atrium receives venous blood from the inferior and superior venae cavae and the coronary sinus. The blood then passes through the tricuspid valve into the right ventricle. 2, With each contraction, the right ventricle pumps blood through the pulmonic valve into the pulmonary artery and to the lungs. 3, Oxygenated blood flows from the lungs to the left atrium by way of the pulmonary veins. 4, It then passes through the mitral valve and into the left ventricle. 5, As the heart contracts, blood is ejected through the aortic valve into the aorta and thus enters the systemic circulation.

4. Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 4 Fig. 32-2. Anatomic structures of the heart and heart valves.

5. Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 5 Fig. 32-3. Coronary arteries and veins.

6. Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 6 Fig. 34-4. Location of pain during angina or myocardial infarction.

7. Conduction system is a specialized nerve tissue responsible for creating and transporting the electrical impulse or action potential This impulse initiates depolarization and subsequently cardiac contraction Electrical impulse is initiated by the sinoatrial ( SA) node, the pacemaker of the heart. Impulses generated by SA nodes travels through the intraatrial pathways to depolarize the atria resulting in a contraction Pathway of the conduction system : SA nodes – AV nodes – bundle of his – left and right bundle branches – purkinje fibers Climax of the cardiac cycle is the ejection of blood to the pulmonary and systemic circulation It end with repolarization : resting polarized state Conduction system Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc.

8. Electrical activity of the heart can be detected on the body surface through the electrodes placed strategically and is recorded on an electrocardiogram. The letters : P, QRS, T, AND U are used to identify the separate waveforms P wave : first positive deflection, begins with the firing of the SA node and represents the depolarization of the fibers of atria. QRS complex : represents the depolarization from the AV node through the ventricles T wave : represents the repolarization of the ventricles U wave : not always seen, is the repolarization of the purkinje fibers or hypokalemia Intervals between these waves ( PR, QRS, QT ) reflect the length of time it takes for impulse to travel from one area of the heart to another. electrocardiogram electrocardiogram Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc.

9. 9 Fig. 32-8. Relationship of electrocardiogram, cardiac cycle, and heart sounds.

10. P wave : 0.06 – 0.12 sec PR interval : 0.12 – 0.20 QRS interval : 0.08 – 0.12 QT interval : 0.34 – 0.43 EKG EKG Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc.

11. 11 Fig. 34-4. Location of pain during angina or myocardial infarction.

12. Systole: Contraction of myocardium Diastole: Relaxation of myocardium Cardiac output: Amount of blood pumped by each ventricle in 1 minute  CO = SV × HR Cardiac index: CO divided by body surface area ( more accurate ) Mechanical System Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 12

13. Preload  Volume of blood in ventricles at the end of diastole Contractility Afterload  Peripheral resistance against which the left ventricle must pump Factors Affecting Cardiac Output Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 13

14. A patient is receiving a drug that decreases afterload. To evaluate the effect of the drug, the nurse monitors the patient’s: 1. Heart rate. 2. Lung sounds. 3. Blood pressure. 4. Jugular vein distention. Audience Response Question Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 14

15. Vascular system  Blood vessels Arteries, arterioles Veins, venules Capillaries Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 15

16. Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 16 Fig. 32-5. Comparative thickness of layers of the artery, vein, and capillary.

17. Regulation of the cardiovascular system  Autonomic nervous system  Baroreceptors  Chemoreceptors Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 17

18. Consists of sympathetic and parasympathetic nervous system Sympathetic system : stimulation of sympathetic system will increases the HR, this effect is mediated by specific sites in the heart called the beta adrenergic receptors that are receptors for norepinephrine and epinephrine. Parasympathetic system : mediated by vagus system. Causes the a decrease in HR. Effect of blood vessels : sympathetic nervous system : the alpha 1 adrenergic receptors – increased stimulation causes vasoconstriction and decreased stimulation causes vasodilation Parasympathetic nerves have selective distribution in the blood vessels Autonomic Nervous System Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc.

19. Baroreceptors are found in the aortic arch and the carotid sinus Sensitive to stretch and pressure within the arterial system ex high blood pressure, fluid overload If increased fluid is sensed, massages are related to the brain to inhibit the sympathetic nervous system and enhancement of the parasympathetic system, causing a decrease in HR, and peripheral vasodilation. Decrease in arterial causes an opposite effect. Baroreceptors Baroreceptors Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc.

20. Located in the aortic and carotid bodies Chemoreceptors initiate changes in HR and arterial pressure in response to increased arterial co2, decreased o2, and decreased plasma PH ( acidosis) Chemoreceptors Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc.

21.  Blood pressure ( BP = CO X SVR Measurement of arterial blood pressure Pulse pressure : difference between SBP and DBP Mean arterial pressure : MAP = ( SBP + 2DBP) /3, MAP > 60 indicates organ perfusion Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 21

22. Age alters the cardiovascular response to physical and emotional stress. Heart valves become thick and stiff. Frequent need for pacemakers Less sensitive to β-adrenergic agonist drugs Increase in SBP; decrease or no change in DBP Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 22

23. Noninvasive studies  Blood studies  Chest x-ray  Electrocardiogram  Resting ECG  Ambulatory ECG monitoring  Event monitor or loop recorder  Exercise or stress testing  6-minute walk test Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 23

24. Chest X-ray Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 24 Fig. 32-9. Chest radiograph: Standard posterior-anterior view.

25. A patient arrives at an urgent care center after experiencing unrelenting substernal and epigastric pain and pressure for about 12 hours. The nurse reviews laboratory results with the understanding that at this point in time, a myocardial infarction would by indicated by peak levels of: 1. Troponin T. 2. Homocysteine. 3. Creatine kinase-MB. 4. Type b natriuretic peptide. Audience Response Question Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 25

26. Noninvasive studies  Echocardiogram  Nuclear cardiology Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 26

27. Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 27 Fig. 32-10. Apical four-chamber two-dimensional echocardiographic view in a normal patient. LA, Left atrium; LV, left ventricle; MV, mitral valve; RA, right atrium; RV, right ventricle; TV, tricuspid valve.

28. Noninvasive studies (cont’d)  Magnetic resonance imaging  Computed tomography Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 28

29. Computed Tomography Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 29 Fig. 32-11. Examples of coronary calcification of the left anterior descending coronary artery (large arrow) and left circumflex artery (small arrow) as seen on electron beam computed tomography.

30. Invasive studies  Cardiac catheterization and coronary angiography  Intracoronary ultrasound  Fractional flow reserve  Electrophysiology study  Blood flow and pressure measurements Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 30

31. Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 31 Fig. 32-12. Normal left coronary artery angiogram.

32. A patient returns to the cardiac observation area following a cardiac catheterization with coronary angiography. Which of the following assessments would require immediate action by the nurse? 1. Pedal pulses are 2+ bilaterally. 2. Apical pulse is 54 beats/minute. 3. Mean arterial pressure is 72 mm Hg. 4. ST-segment elevation develops on the ECG. Audience Response Question Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc. 32