1. ASSESSMENT OF CARDIOVASCULAR FUNCTION
NUR240
Lecture 1
J. Borrero 9/10

2. LECTURE OBJECTIVES
Review anatomy & physiology of the cardiovascular system.
Discuss relevant aspects of the patient history.
Describe physical assessment of cardiovascular status.
Review diagnostic procedures, tests and medications relative to the cardiovascular system.

3. Anatomy & Physiology (What makes it “tick”!)
Functions of the heart & CV system
Pumps blood to tissues to supply O2 & nutrients
Remove CO2 & metabolic wastes

4. Anatomy & Physiology CARDIAC CELLS HAVE UNIQUE PROPERTIES
AUTOMATICITY  CELLS CONTRACT INDEPENDENTLY (THEY INITIATE THEIR OWN IMPULSE)
EXCITABILITY  ION SHIFT
CONDUCTIVITY  TRANSMIT IMPULSE TO ANOTHER CARDIAC CELL
CONTRACTTILITY  HOW WELL THE CELL CONRACTS

5. Anatomy & Physiology Serous fluid lubricates and prevents friction
PERICARDIUM / PERICARDIAL SAC
Protects heart from trauma
Serous fluid lubricates and
prevents friction
Prevents heart from over filling

6. CIRCULATION PATHWAY HEART IS DIVIDED INTO TWO SIDES RIGHT & LEFT
ALL BLOOD RETURNS TO THE HEART THROUGH THE ATRIA
ALL BLOOD LEAVES THE HEART FROM THE VENTRICLES

7. CORONARY ARTERIES Supply blood to MYOCARDIUM BRANCHES:
LEFT MAIN CORONARY ARTERY
L ANTERIOR DESCENDING (LAD)
L CIRCUMFLEX (LCX)
RIGHT CORONARY ARTERY
POSTERIOR
MARGINAL

8. CORONARY ARTERIES
(L) ARTERY
CIRCUMFLEX
(R) ARTERY
LAD

9. CONTRACTION OF CARDIAC MUSCLE
The heart can’t pump unless an electrical stimulus occurs
Action Potential (AP) – electrical change
(depolarization = contraction)
Brought about by release of calcium
(+ charge) into cells
Intrinsic Pacemakers – depolarize and generate the AP

10. CONTRACTION OF CARDIAC MUSCLE
The pacemaker with the fastest rate of depolarization stimulates the AP
SA node ( bpm)- Upper R atrium
AV node (40-60 bpm)- Lower R atrium
Other pacemakers ( 40)
Cardiac muscle contractions last roughly 10 X’s longer than those of skeletal muscle fibers

11.  K, Ca & Mg lead to dysrhythmia, weakness
DISRUPTION IN SERUM ELECTROLYES CAN RESULT IN ALTERATION IN CARDIAC CYCLE
 K, Ca & Mg lead to dysrhythmia, weakness
 Ca leads to  strength of contraction
 Na leads to general weakness & less Na to initiate action potential
K leads to dysrhythmias
K is principal intracellular ion

12. MONITORING MOVEMENT OF THE CRDIAC ACTION POTENTIAL (AP)
EKG – monitors the movement of the AP, the electrical changes NOT the mechanical changes that follow
Auscultating heart sounds, palpating pulses and measuring pressures monitor the mechanical changes

13. CARDIAC CYCLE
CARDIAC CYCLE – all the activities occurring in the heart during one contraction, and subsequent period of relaxation. Graphically represented on an EKG (ECG)

14. CARDIAC CYCLE
EKG – A 12 lead EKG is a graphic record of the electrical forces produced by the heart

15. CARDIAC CYCLE Part of Cycle Representation P wave PR Interval
QRS Complex
ST Segment
T Wave
R-R Interval

16. CARDIAC CYCLE
Polarized (resting) cell – represented on EKG as baseline or isoelectric line
Depolarization – impulse over specialized cardiac cells (not neuromuscular impulse)
Repolarized cell – returns to normal. Na moves out of cell, K moves in – requires ATP
Note: ischemic tissue may cause problem

17. ELECTRODE POSITIONS “LEADS”
Leads measure electrical activity between 2 points
Movement toward  electrode causes positive deflection
Movement away from  electrode causes negative deflection

18. ELECTRODE POSITIONS
A 12 Lead EKG shows electrical activity from 12 different positions in the heart, concentrating on (L) ventricle
A 14 Lead EKG includes (R) ventricle activity

19. STROKE VOLUME (SV) & CARDIAC OUTPUT (CO)
SV – amount of blood ejected by 1 ventricle in 1 beat
CO – volume ejected in 1 min
Control of SV and HR = SV&HR are continually adjusted by the body, and are affected by the return of blood from the tissues (think of exercise)
CO = SVxHR

20. STROKE VOLUME (SV) & CARDIAC OUTPUT (CO)
Extrinsic control of HR is a more powerful way of controlling CO than changing SV
 CVP causes stretching of (R) atrial muscle which stimulates SNS &  HR (to help pump all the blood returned to it)
Remember “Starling’s Law”

21. STROKE VOLUME (SV) & CARDIAC OUTPUT (CO)
Stretch baroreceptors (aorta & carotid) detect in pressure which stimulates SNS & HR  (to ensure adequate blood supply to heart/ brain)
If  pressure detected, then PSNS is stimulated & HR is slowed (vagus nerve) (prevents excess arterial pressure which can damage organs)

22. CARDIAC LOAD
Preload = degree of myocardial fiber stretch at the end of diastole and just before contraction
Afterload = pressure against which ventricles must eject blood. This pressure is affected by systemic vascular resistance (SVR)

24. CARDIAC ASSESSMENT
Cardiac status of all patients should be routinely assessed. Everyone has a
Subjective CP
Dyspnea
Fatigue
Objective

25. IMMEDIATE NURSING INTERVENTIONS FOR ACUTE CARDIAC EVENT MOVIE Acronym
M- Monitor for pain
O- O2 and pulse ox
V- Vital signs
I- Intravenous fluids
E- EKG monitoring
Anything else??

26. Pain Assessment SLIDA or Precipitating/alleviating factors Quality
Radiation
Severity
Timing

27. OTHER ELEMENTS OF CARDIAC ASSESSMENT
Previous cardiac hx
Other medical conditions that may affect heart function
Chest injury
Previous heart surgery
Past medical hx
Medications: prescribed, OTC, herbals
Activity tolerance
Health habits
Family hx

28. EXAMINATION Inspection Palpation Percussion-?
Auscultation = S1, S2 at PMI
Aortic
Pulmonic
Tricuspid
Mitral

29. Heart Rhythm Regular, Irregular, Regular Irregular
Abnormal Sounds: Gallops
Murmurs
Bruits
S3 ventricular gallop – heard in early diastole
S4 atrial gallop – generally abnormal

30. Assessment of Murmurs
Turbulent blood flow in valvular disorders and septal defects
Timing of murmurs is a must!
Systolic murmurs occur between S1 & S2
Diastolic murmurs occur between
S2 & S1
Grade 1 – 6 identifies intensity of murmur

32. Other assessments
Jugular vein pressure – assess JVD which reflects increased filling volume and pressure on (R) side of heart
 JVD associated with (R) HF, SVC obstruction (Normal is 3-10cm H20)
Pulse deficit – the difference between apical HR and peripheral pulse-associated with Afib, and heart blocks
Pulse pressure – the difference between systolic & diastolic pressure

33. Other assessments
Respiratory: Lung sounds = rate, rhythm, quality, sputum
GI-Abdomen
Peripheral Vascular:Lower extremities

34. Diagnostic Procedures
EKG 12 Lead
continuous cardiac monitoring
holter monitor
Chest x-ray – detects enlargement of heart & pulmonary congestion

35. Diagnostic procedures
Echocardiography – ultrasound that reveals size, shape and motion of cardiac structures
Evaluates heart wall thickness, valve structure, differentiates murmurs
TEE – transesophageal echocardiography provides a clearer image because less tissue for sound waves to pass through

36. Diagnostic procedures
Angiography / cardiac catherization
determines coronary lesion size, location, evaluate (L) ventricular function, measures heart pressures
Exercise tolerance test
Radionuclide Imaging

37. Lab Studies
Cardiac enzymes = enzymes are released when cells are damaged (MI). Enzymes are found in many tissues/muscles, and some are specific to cardiac tissue.
Serial measurement can aid in dx, and monitor course of MI
Cardiac enzymes =
CPK – MB (CK-MB),myoglobin, Troponin
In general, the greater the rise in the serum level of an enzyme, the greater the degree or extent of damage to the muscle.
LDH

38. Blood studies Electrolytes Lipid panel CBC C – Reactive Protein
BNP- Human B-Natriuretic Peptide
Blood coags-PT/PTT/INR

39. Lipid Panel Desirable Borderline High Total Cholesterol Under 200
240 or >
LDL
Under 130
160 or >
HDL
30-80
Elevated levels neg
correlated with CAD and may be protective
Triglycerides
40-150

40. C Reactive Protein Hs-CRP Level Risk < 1.0mg/L Low risk of CVD
Average risk of CVD
>3.0 mg/L
High Risk of CVD
Used to indicate an inflammatory illness. May be valuable in predicting coronary events.

41. NCLEX TIME
Mary is attending a sophomore level nursing class on anatomy and physiology. Which statement, if made by Mary, demonstrates a good understanding of the anatomy and physiology of the heart?
A."The heart is encapsulated by a protective coating called the endocardium.“
B."The SA node is considered the main regulator of heart rate.“
C."The left atrium receives deoxygenated venous blood from all peripheral tissues.“
D."Stroke volume is the amount of blood ejected by the right ventricle during each diastole B

42. NCLEX TIME
Kirsten is completing her graduate clinical rotation in a large urban teaching hospital in a medical coronary care unit (CCU). Which observation demonstrates a good understanding of completing a thorough cardiac examination?
A. In an obese client, an adult cuff size of 12 to 14 cm is preferable.
B.The carotid artery on the neck is auscultated to assess for the presence of a bruit.
C.The apical impulse is auscultated over the fifth intercostal space in the midclavicular line.
D.Palpation is used to determine cardiac size.
B- 4 or 5 ICS

43. NCLEX TIME
Edward is a 40-year-old white male. He is an accountant who works on average 11 hours per day. He reports feeling stressed each day, even with mundane things such as a traffic jam. His father had a massive myocardial infarction at the age of 48. His mother has a history of congestive heart failure. He seldom has time to exercise, but does eat balanced meals when possible, although he does not get to eat three meals a day. Select all factors that place Edward at risk for heart disease.
A.Family history
B.Age
C.Coping-stress tolerance
D.Race
E.Occupation
A, C, E