Cardiac Function Flashcards
Primary functions of the heart
Transport Oxygen
Transport Nutrients
Deliver Waste Products to Organs
Right side circulation is
Pulmonary Circulation
Left side circulation is
Systemic circulation
What side is more muscular?
The left
The left side pumps through
the left ventricle
The heart pumps about ____ of blood a minute
5 quarts
A normal heart beats about ____ times a day
100,000 times
The three layers of the heart
Endocardium
Myocardium
Epicardium
The inner layer of the heart is
Endocardium
The middle layer of the heart is
Myocardium
The outer layer of the heart is
Epicardium
This layer lines the heart
endocardium
This layer is the muscle
Myocardium
This layer is the sac that surrounds the heart and attaches to the diaphragm and thorax
Epicardium
Valves prevent
backflow
Backflow causes
the heart to work harder
When a portion of the valve balloons backwards into the left atrium. Blood regurgitates back into the left atrium
Mitrovalve prolapse
MVP
Mitrovalve Prolapse
The gatekeepers of the heart
the valves
Maybe asymptomatic but is treated symptomatically
Mitrovalve prolapse
Impulses Stimulated from the SA Node in
the right atrium
Valve that separates the right atrium from the right ventricle
Tricuspid valve
Valve that separates the left atrium from the left ventricle
Mitral valve
Valve that separates the right ventricle from the pulmonary system
The pulmonary valve
Valve that separates the left ventricle from the aorta
The aortic valve
The pulmonary and aortic valves are called
Semilunar valves
The extensive network of vessels in the body is for the purpose of
Tissue perfusion
Gas exchange occurs in the
Capillaries
These blood vessels are thick walled to withstand constant pressure
Arteries
These blood vessels cannot withstand high pressure
capillaries
Valve problems are the major cause of
Low bloodflow
What can affect the valves?
Inflammation, infection, trauma, congenital defects
SA Node
Sino-Atrial Node
This is located in the anterior portion of the right atrium
SA node
This is called the pacemaker of the heart
Sinoatrial node (SA Node)
Firing rate of the SA node
60-100 bpm
AV Node
Atrioventricular Node
This receives the impulse from the SA node and blankets the impulse over the ventricles
AV node
Firing rate of the AV node
40-60 bpm
SA node responds to
electrolytes
Collection of heart muscle cells specialized for electrical conduction
Bundle of His
Firing rate of Bundle of His
30-40 bpm
Stimulation of the ventricular myocardial cells initiating contraction
Purkinje Fibers
Firing rate of Purkinje Fibers
20-30 bpm
If the electrical wiring of the heart does not fix in an efficient manner
the heart becomes an inefficient pump.
Adequate oxygenation to cells, tissues, organs, body systems may be compromised if the heart
is ineffective
In between systole and diastole, the heart
rests
Systole =
Contraction
Diastole =
Relaxation
During systole, the chambers of the heart become smaller, due to
Contraction of the myocardial cells.
During systole, blood is ejected from the Left ventricle into
the aorta
During diastole, the chambers of the heart expand, due to
Relaxation of the myocardial cells
During diastole,
filling of blood within the heart chambers, in preparation for
the next contraction
Diastole takes _____ in comparison to systole
twice as long
Each ventricle ejects approximately _________ of blood per heart beat
70mL
Total cardiac output per minute
5 L/min
SV
Stroke volume
The amount of blood pumped by the heart each minute
Cardiac output
Normal cardiac output is
3.5 - 8 L/min
Cardiac output varies according to
Metabolic demand
CO = SV x HR
Cardiac output = Stroke volume x Heart Rate
Amount of blood ejected from the LV, per contraction (heart beat)
Stroke volume (SV)
SV is determined by three things
Strength of muscle
Volume
Resistance to bloodflow
If BP is high, the SV will
decrease
Which side of the heart has more blood supply and is more muscular?
The left side
Average resting SV is
70mL
The heart is unique because of it
automaticity. It conducts itself
Extracts _______ % of oxygen carried by RBCs
70% - 80%
Myocardial cells are fed by the
coronary vessels
Tissue hypoxia causes coronary arteries to
dilate & increases coronary blood flow without symptoms
MVP symptoms
SOB, chest pins, anxiety, and palpatations
Myocardial supply can increase up to _____ to meet metabolic demands
6 times
Heart disease presents differently in
men and women
Do men have larger blood vessels than woman?
Yes
Blood flow from the heart goes to the arteries then
the arterioles
Blood flow from the arteries to the arterioles then goes to
capillaries
Blood flow from the capillaries goes to the
venules
Blood flow from the venules goes to
the veins
Blood flow from the veins goes
back to the heart
Function of the Cardiovascular System depends on
SA Node
Emptying and filling properly
strength to contract
Factors affecting cardiovascular function
Elevated serum lipid levels HTN Cigarette smoking DM Lifestyle (sedentary vs. active) Stress & obesity Metabolic syndrome Excessive salt intake
Changes in activity tolerance leads to
loss of elasticity in the vessels
If the SA nodes are not firing
AV nodes start to fire
Most common heart problems presenting in women
exhaustion and cold sweats
Women begin to have heart problems after menopause
Because estrogen is protective
If the heart does not return to normal flow
There will be death of tissues and organs
If there is no blood flow, the kidneys will begin to shut down and
decrease urine output
Normal daily salt intake
2g
A cluster of symptoms is
Metabolic syndrome
Large meals and/ or exercise increases
Metabolic demand
Cholesterol should be below
200
HDL should be
above 60
LDL should be below
100
Triglycerides should be below
150
OTC cold meds may raise
BP and heart rate
EPHEDRINE (wt. loss herbals) can cause
arrhythmias
Ephedra can interact with antihypertensive Rxs or antidepressants to
DANGEROUSLY ELEVATE b/p & HR
ALCOHOL INTAKE RECOMMENDED:
less than 2 oz/day
COCAINE
Associated w/ sudden cardiac arrest
INCREASING OXYGEN DEMAND
DECREASING MYOCARDIAL BLOOD SUPPLY
OVERDOSES OF OPIATES (i.e. HEROIN, MORPHINE) may cause
Severe HYPOtension & Respiratory Arrest
May induce Pulmonary Edema
Birth control changes
the viscosity of blood
Altered Cardiovascular function:
Pulse character, HR
Weak, bounding
Altered Cardiovascular function:
Respiration
Increase of SOB
Altered Cardiovascular function:
Rubor
Redness or flushing
Altered Cardiovascular function:
Skin temp
Cold, clammy
Altered Cardiovascular function:
Skin, appearance
Hairloss and clubbing
MI pain is from
lack of blood flow causes the area to dies
Restriction of blood flow
ischemia
Altered cardiovascular function:
Arterial dysfunction
From Occlusions, plaque, and aneurysm
Altered cardiovascular function:
Capillary dysfunction
Leaky cause of tissue edema
Altered cardiovascular function:
Venous dysfunction
decrease blood volume becomes pooled (edema)
TIA
Trans ischemic attack
Thrombus halts
blood flow
Claudication is pain caused by
too little blood flow to muscles during exercise.
Legs on people with cardiovascular problems are
Hairless
Complaints of chest pain with activity
Warrants investigation
Five points of stroke screening
Change in LOC Change in vision (usually unilateral) Change in Movement Complain of numbness or tingling Speech - drop of one side of face
Stroke is a code
gray
Strokes are identified by
clot or bleed
Calf pain at dorsiflexion of the foot
Homan’s sign
Homan’s sign can be
deep vein thrombosis
Pitting Edema:
Slight indentation (2mm)
+1
Pitting Edema:
Deeper pit (4mm)
+2
Pitting Edema:
Deep pit (6mm) Remains several seconds after pressing
+3
Pitting Edema:
Deeper pit (8mm) may remain for minutes
+4 called Frank swelling
Pitting Edema:
No pitting. Swelling to point of shiny warm skin
+5 or Brawny Edema
Diagnostic test for :
MYOCARDIAL DAMAGE / CARDIAC ISHCHEMIA
ALTERATIONS OF HEART RHYTHM
PROBLEMS of CONDUCTION SYSTEM.
EKG/ECG
Diagnostic test for :
STRUCTURAL HEART DEFECTS MYOCARDIAL MUSCLE THICKNESS AND MOTION STRUCTURE AND MOTION OF VALVES SIZE OF CHAMBERS & PRESENCE OF FLUID AROUND HEART
Echo/ Sonogram
Diagnostic test for:
DETERMINE PATENCY & SHAPE OF BLOOD VESSELS.
DIRECTION & VOLUME OF BLOOD FLOW
Doppler studies
Diagnostic test for:
DETERMINES PRECISE INFO.:
VALVE FXN & CARDIAC MUSCLE STRENGTH
MORE INVASIVE PROCEDURE
USE OF DYE (PT MAY FEEL FLUSHING SENSATION)
Cardiac catheterization
Diagnostic test for:
USES DYE TO OUTLINE BLOOD VESSELS AND CONFIRM OR R/O BLOCKAGES & DETECT ANEURYSMS
Angiography
Diagnostic test for:
Test done to determine problems with ELECTRICAL CONDUCTION or AUTOMATICITY in the heart.
Wires threaded through large veins & arteries.
Attempts made to reproduce dysrhythmias
Electrophysiology
Diagnostic test for:
Establish general size & shape
PULMONARY CONGESTION or EDEMA
Confirm placement of indwelling heart catheters & Pacemakers
Chest X-Ray
Diagnostic test done when there is an arrhythmia. It deadens the area to stop the arrhythmia
Electrophysiology
Diagnostic test similar to cardiac cath
Electrophysiology
Low hemoglobin
anemia
Anemia may cause
SOB
Blood test done every 6-8 hrs
Triponin
Protein released when there is cardiac muscle damage
Triponin
Normal triponin levels
0.0 - 0.4ng/mL
BNP
B-type natriuretic peptide, brain natriuretic peptide
If cardiac arrest is occuring
defribulation is needed
