The document discusses cardiovascular anatomy and physiology. It describes the structures of the heart including the layers (pericardium, epicardial fat, myocardium, endocardium), chambers (left and right atria and ventricles), and valves. It also discusses the cardiac conduction system including the sinoatrial node, atrioventricular node, bundle of His, and Purkinje fibers. Hemodynamic monitoring techniques are covered such as intra-arterial blood pressure monitoring, central venous pressure monitoring, pulmonary artery pressure monitoring, and mixed venous oxygen saturation monitoring. Physical exam skills related to cardiovascular assessment are also outlined.

1. Cardiovascular
Chapter 2

2. Cardiovascular Anatomy and Physiology

4. Structures of the Heart
• The heart is situated in the anterior thoracic cavity, just behind the
sternum
• The right ventricle constitutes the majority of the anterior surface
(closest to the chest wall), the inferior surface (directly above the
diaphragm).
• The left ventricle makes up the anterolateral (front and side) and
posterior surfaces.
• The base of the heart is superior (atrial and great vessel level), and
the tip (apex) is inferior (ventricular level), above the diaphragm

6. Size and Weight of the Heart
• In the adult, this averages 12 cm in length and 8 to 9 cm in breadth at
the broadest part. In adult men, the weight of the normal heart
averages 310 g, and in women averages 255 g.
• No significant differences exist in ventricular wall thickness between
men and women.
• Pathologic conditions such as hypertension increase the weight of the
heart muscle because of ventricular hypertrophy.

7. Layers of the Heart
1. Pericardium.
 The heart and the origins of the great vessels are surrounded and enclosed by the pericardium. The outermost fibrous
pericardium is a thick envelope that is tough and inelastic. Ligaments anchor the outer pericardium to the diaphragm
and the great vessels such that the heart is maintained in a fixed position within the thoracic cavity
 The pericardium also provides a physical barrier to infection.
2. Epicardial Fat.
 In adults, a layer of adipose tissue is typically present beneath the visceral pericardium and may surround the heart.
This epicardial fat accumulates along the routes of the major coronary arteries and veins. Autopsy data indicate that
epicardial fat increases until age 20 to 40 years, but thereafter, the quantity does not depend on age
3. Myocardium.
 The next layer of the heart is the myocardium, a thick, muscular layer. This layer includes all of the atrial and
ventricular muscle fibers necessary for contraction.
 The left ventricle is much thicker than the right ventricle or the atria.

8. Layers of the Heart … cont.
4. Endocardium.
 The innermost layer is the endocardium, which is a thin layer of endothelium and connective tissue lining the inside of
the heart. This layer is continuous with the endothelium of the great vessels to provide a continuous closed system.

9. Cardiac Chambers
• The human heart has four chambers: the left and right atria and the
left and right ventricles. The atria are thin-walled and normally low-
pressure chambers.
• Atrial contraction, also known as atrial kick, contributes
approximately 20% of blood flow to ventricular filling; the other 80%
occurs passively during diastole.
• The healthy left ventricle is about 10 to 13 mm thick, and the interior
chamber appears round in cross-section. The healthy right ventricle is
approximately 3 mm thick.

11. Cardiac Valves

12. Conduction System

13. Conduction System … cont..
• The SA node is considered the natural pacemaker of the heart
• Atrioventricular Node.
The AV node performs four essential functions to support cardiac
conduction:
1. The AV node delays the conduction impulse from the atria (0.8 to
1.2 seconds) to provide time for the ventricles to fill during diastole.
2. The AV node controls the number of impulses that are transmitted
from the atria to the ventricles.
3. The AV node controls the number of impulses that are transmitted
from the atria to the ventricles.
4. The AV node can conduct retrograde (backward) impulses through
the node.

14. Conduction System … cont..
• Bundle of His, Bundle Branches, and Purkinje Fibers.
Electrical impulses are conducted in the ventricles through the bundle
of His, the bundle branches, and the Purkinje fibers

15. Coronary Blood Supply
• The coronary circulation consists of those vessels that supply the
heart structures with oxygenated blood (coronary arteries) and then
return the blood to the general circulation (coronary veins).
• The right coronary artery (RCA) serves the right atrium and the right
ventricle. RCA is dominant, supplying the posterior cardiac wall
• The left coronary artery is a short but important artery that divides
into two large arteries—the left anterior descending (LAD) and the
circumflex (Cx) arteries.

17. Cardiac Output
• Cardiac output (CO):
is defined as the volume of blood ejected from the heart in 1 minute.
Normal CO in the human adult is approximately 4 to 8 L/min.
• CO can be made specific to body size by using the person’s height and
weight to determine the cardiac appendix (CI).
For example, for a person with an HR of 72 and an SV of 70 mL, the CI
would be:

18. Preload, afterload, and contractility contribute to
the heart’s stroke volume.

19. Cardiovascular Clinical
Assessment

20. Cardiovascular History
•The appendix 1 shows the Cardiovascular
History contents

21. PHYSICAL EXAMINATION related to Cardiac
• Inspection (appendix 2)
Face
Thorax
Abdomen
Nail Beds and Cyanosis
Lower Extremities
Posture
Weight
Mentation
Jugular Veins
Abdominojugular Reflux
Thoracic Reference Points
Apical Impulse
• Palpation (appendix 2)
Arterial Pulses
Carotid Pulses
Brachial, Ulnar, and Radial
Pulses
Femoral Pulses
Popliteal Pulses
Dorsalis Pedis and Posterior
Tibial Pulses
Descending Aorta Pulse
Capillary Refill
Edema

22. PHYSICAL EXAMINATION related to Cardiac
• Auscultation
(appendix 2)
Blood Pressure Measurement
Noninvasive Blood Pressure
Monitoring
Orthostatic Hypotension
Blood Pressure Cuff Size
Korotkoff Sounds.
Auscultatory Gap
Automated Blood Pressure
Devices
Pulse Pressure.
Pulse Pressure.
Pulse pressure describes
the difference between
systolic and diastolic
values. The normal pulse
pressure is 40 mm Hg.
In the critically ill patient, a
low blood pressure is
frequently associated with
a narrow pulse pressure.

23. Heart Murmurs
• Heart valve murmurs are prolonged extra sounds that occur during
systole or diastole. Murmurs are produced by turbulent flood flow
through the chambers of the heart, from forward flow through
narrowed or irregular valve openings, or backward regurgitant flow
through an incompetent valve.
• Murmurs are characterized by specific criteria:
Timing: place in the cardiac cycle (systole/diastole)
Location: where it is auscultated on the chest wall (mitral or aortic area)
Radiation: how far the sound spreads across chest wall Quality: whether the
murmur is blowing, grating, or harsh
Pitch: whether the tone is high or low

25. Bedside Hemodynamic
Monitoring

26. A. Intra-arterial Blood Pressure Monitoring
• Intra-arterial blood pressure monitoring
• Indications
• is indicated for any major medical or surgical condition that compromises
cardiac output (CO), tissue perfusion, or fluid volume status.
• The system is designed for continuous measurement of three blood pressure
parameters: systole, diastole, and mean arterial blood pressure (MAP).
• The direct arterial access is helpful in the management of patients with acute
respiratory failure who require frequent arterial blood gas measurements.

27. Intra-arterial blood pressure monitoring …cont
• Nursing Management
1. This MAP formula can be calculated by hand or with a calculator,
where diastole times 2 plus systole is divided by 3 as shown in the
formula below:
• The normal range 70- 100 mm hg

28. Intra-arterial blood pressure monitoring …
cont
• Nursing management … cont.
2. Infection. Infection was once believed to be rare in arterial catheters
because of the rapid arterial blood flow. New evidence suggests that
arterial catheters are associated with the same risk of bloodstream
infections as central venous catheters (CVCs)
3. Perfusion Pressure
Example:
• Mr. A: BP, 90/70 mm Hg; MAP, 76 mm Hg
• Mr. B: BP, 150/40 mm Hg; MAP, 76 mm Hg

29. critical thinking for example

30. HEMODYNAMIC PRESSURES AND CALCULATED
HEMODYNAMIC VALUES
appendix 3

31. B. Central Venous Pressure Monitoring
• Indications
CVP monitoring is indicated whenever a patient has significant
alteration in fluid volume (see appendix 3)
• Central Venous Catheter Complications
Air Embolus.
Thrombus Formation.
Infection.

32. Systemic Vascular Resistance.
• Resistance to ejection from the left side of the heart is estimated by
calculating the SVR. The formula, normally calculated by the bedside
computer, is as follows:
• The normal range (see appendix 3)

33. C. Pulmonary Artery Pressure Monitoring
• The pulmonary artery (PA) catheter is the most invasive of the critical
care monitoring catheters. It is also known as a right heart catheter or
Swan-Ganz catheter
• Indications
• The thermodilution PA catheter is reserved for the most
hemodynamically unstable patients, for the diagnosis and evaluation
of heart disease,38 and shock states.

34. Relationship of the pulmonary artery occlusion pressure (PAOP) (i.e., wedge
pressure) to the left ventricular end-diastolic pressure (LVEDP) (i.e., preload).

35. D. Continuous Monitoring of Venous Oxygen Saturation
• Indications
Continuous monitoring of venous oxygen saturation is indicated for the critically
ill patient who has the potential to develop an imbalance between oxygen supply
(Sao2) and metabolic tissue demand by sampling desaturated venous blood from
the PA catheter distal tip. This sample is called mixed venous oxygen saturation
(Svo2) normal value 60% - 80%.
This includes patients in severe sepsis or shock, those after high-risk cardiac
surgery, and patients with ARDS.
Under normal conditions, the cardiopulmonary system achieves a balance
between oxygen supply and demand. Four factors contribute to this balance:
1. Cardiac output (CO)
2. Hemoglobin (Hgb )
3. Arterial oxygen saturation (Sao2)
4. Tissue oxygen metabolism (Vo2)

36. D. Electrocardiography
• The ECG records electrical changes in heart muscle caused by an action
potential.
• Action potential phases:
1. Phase 0. During phase 0 (depolarization), the electrical potential changes
rapidly from a baseline of −90 mV to +20 mV and stabilizes at about 0
mV.
2. Phases 1 and 2. During phases 1 and 2, an electrical plateau is created,
and during this plateau, mechanical contraction occurs.
3. Phase 3. During phase 3 (repolarization), the electrical potential again
changes, this time a little more slowly, from 0 mV back to −90 mV.
4. Phase 4. During phase 4 (resting period), the chemical balance is restored
by the sodium pump

37. Correlation of the action potential of a ventricular myocardial cell with the electrical events
recorded on the Surface ECG.

38. Cont…. 12-Lead Electrocardiogram.
• The standard 12-lead ECG provides a picture of electrical activity in the
heart using 10 different electrode positions to create 12 unique views of
electrical activity occurring within the heart.
• Standard Limb Leads.
oleft arm (LA), right arm (RA), left leg (LL), and right leg (RL).
oLeads I, II, and III are bipolar limb leads that use limb lead electrodes paired
as the positive and negative poles
Lead I—positive electrode at LA and negative electrode at RA
Lead II—positive electrode at LL and negative electrode at RA
Lead III—positive electrode at LL and negative electrode at LA

39. Cont…
• Augmented Vector Leads.
• The augmented vector leads, labeled aVR, aVL, and aVF, are created from
the derived electrode pairs previously described.
• Precordial Leads.
The six precordial, or left chest, leads are labeled as V leads and are
distributed in an arc around the left side of the chest.
The six electrodes are placed on the chest in the
following locations71:
V1—fourth intercostal space at the right sternal border
V2—fourth intercostal space at the left sternal border
V3—midway between V2 and V4
V4—fifth intercostal space in the midclavicular line
V5—in the horizontal plane of V4 at the anterior axillary line or, if the anterior axillary
line is ambiguous, midway between V4 and V6
V6—in the horizontal plane of V4 at the midaxillary line

40. Electrocardiographic Analysis
• Specialized
Electrocardiographic Paper.
oLarge box contains 25 small
boxes
oOne small box (1 mm wide) is
equivalent to 0.04 second,
and one large box (5 mm
wide) represents 0.20 second

41. Cont…
• Waveforms.
• P Wave represents atrial depolarization
• QRS Complex. The QRS complex represents ventricular
depolarization, corresponding to phase 0 of the ventricular action
potential.
• T Wave. The T wave represents ventricular repolarization,
corresponding to phase 3 of the ventricular action potential

42. Waveforms cont..

43. Intervals Between Waveforms.
• PR Interval. The PR interval is measured from the beginning of the P
wave to the beginning of the QRS complex. Normally, the PR interval is
0.12 to 0.20 second long and represents the time between sinus node
discharge and the beginning of ventricular depolarization.
• ST Segment.
The ST segment is the portion of the wave that extends from the end of the
QRS to the beginning of the T wave. ST segment is normally flat and at the
same level as the isoelectric baseline.
ST segment elevation of 1-2 mm is associated with acute myocardial injury,
preinfarction, and pericarditis. ST segment depression (decrease from baseline
more of 1-2 mm) is associated with myocardial ischemia.

44. Intervals Between Waveforms. Cont…
• QT Interval.
The QT interval is measured from the beginning of the QRS complex
to the end of the T wave and indicates the total time interval from the
onset of depolarization to the completion of repolarization.
QT interval is less than one half of the R-R interval when measured
from one QRS complex to the next.
A prolonged QT interval is significant because it can predispose the
patient to the development of polymorphic VT, known also as
torsades de pointes.

45. E. Cardiac Monitor Lead Analysis
• During continuous cardiac monitoring, adhesive, pregelled electrodes
are used to obtain an ECG At minimum, this requires three electrodes.
One of the electrodes acts as a positive pole, one as a negative pole,
and one as a ground.

46. F. Hematologic Studies
• Red Blood Cells
• Hemoglobin
• Hematocrit
• White Blood Cells
• Platelets
• Blood Coagulation Studies

47. G. Serum Lipid Studies
• Total Cholesterol
• Low-Density Lipoproteins
• Very-Low-Density Lipoproteins
and Triglycerides
• High-Density Lipoproteins
• Triglycerides

48. H. DIAGNOSTIC PROCEDURES
• Cardiac Catheterization and Coronary Arteriography
• Left-Heart Cardiac Catheterization
• Right-Heart Cardiac Catheterization
Nursing Management
1. Femoral Artery Site Care.
• Applied to the femoral vessels until bleeding has stopped. By The most basic
method is manual pressure or by using compression over the site (C-clamp or
FemoStop)
• After catheterization, the patient remains flat for up to 6 hours
• Site monitoring because Most bleeding occurs within the first 2 to 3 hours
after the procedure.

49. Nursing Management … cont
2. The peripheral pulses located distal to the arterial access site are
monitored closely by the critical care nurse.
3. The patient is encouraged to drink large amounts of clear liquids,
and the intravenous fluid rate is increased to 100 mL/hr to prevent
contrast-induced nephropathy or damage to the kidney
4. The patient is assessed for chest pain (Angina) after the procedure.
Usually, sublingual nitroglycerin is sufficient to relieve the pain,
discomfort, or pressure.
5. Monitor for Dysrhythmias because are always a concern after an
invasive cardiovascular diagnostic procedure.

50. I. Chest Radiography
• Indications
1.Daily chest radiographs are recommended for patients with acute
cardiopulmonary problems and those receiving mechanical ventilation.
2.Patients who require cardiac monitoring but are otherwise stable need only
an admission radiograph.
3.A chest radiograph is obtained when a new thoracic device is placed or there
is a specific question about the patient’s cardiopulmonary status that the
radiograph could address

51. The normal heart size is less than
one half of the diameter of the
chest viewed on the radiograph.
Patients with chronic heart failure
often have cardiomegaly (enlarged
heart),

52. J. Echocardiography
• Echocardiography
uses waves of
ultrasound to obtain
and display images of
cardiac structures.
Normal human
hearing occurs at a
sound frequency of
20 to 20,000 cycles
per second (Hz).