Perfusion Part 1

How many Liters a minute does the heart pump?

5

How many mL a beat dose the heart pump?

60 m

What is the outer layer of the heart?

Pericardium

What are the three layers of the heart?

Epicardium - outer most layer
Myocardium - Middle
Endocardium - closest to the heart

Name the heart valves.

*** Remember: Aunt
Polly
Takes
Meds.***
Atrial
Pulmonic
Tricuspid
Mitral

Follow the 12 steps of blood through the heart.


RIGHT SIDE
1. Superior/Inferior Vena Cava
2. Right Atrium
3. Tricuspid valve
4. Right Ventricle
5. Pulmonic valve
6. Pulmonary Artery

LEFT SIDE
7. Pulmonary Vein
8. Left Atrium
9. Bicuspid Valve
10. Left Ventricle
11. Aortic Valve
12. Aorta

What is the coronary sinus location

posterior portion of the heart

The left coronary artery supplies what?

Left side of the heart

The right coronary artery supplies what?

The right side of the heart

Pre-load is also known as what?

End diastolic volume

Afterload is affected by vascular ______________.

Resistance
If there is high resistance then after load becomes higher.

What problems can cause an increase in afterload pressure?

pulmonary hypertension will increase pulmonary vascular resistance
vascular hypertension will increase vascular resistance
A valve problem such as aortic stenosis will increase it

Why would we want to decrease a patients afterload?

If the ventricles are tired we can give vasodilators

What is afterload?

the pressure the ventricles must work against in order to open the
semilunar valves to pump blood out of the heart

why would you want to decrease a preload?

If your patient is in heart failure and in fluid overload
(Give diuretics! or vasodilators such as nitroglycerin)

Increasing preload will increase _______ ____________.

Stroke volume
(you would do this with something like hypovolemic shock. Give IV
fluids! or you can give drugs like vasopressors to cause constriction
and force more blood via venous return to the heart)

What happens during diastole?

the relaxation of the ventricles and atria allowing them to fill or
the "Pre-Load

What happens during systole?

The contraction of the atria and ventricles or the "after-load

How do you calculate stroke volume?

SV =End diastolic - End systolic

How doe you calculate ejection fraction?

EF = SV/EDV

Blood pressure is the result of what?

Cardiac output (CO) + systemic vascular resistance (SVR)

what is a normal stroke volume range?

60-100 mL/beat

What things can effect cardiac output?

Heart rate
contractility
preload
afterload

If you change the heart rate, contractility, preload or after load,
then the cardiac output changes. But all these things are dependent on what?

Stroke volume

What is the MAP?

Mean arterial pressure
must be > 60 but the brain and kidneys prefer 65-70

what are manifestations of low cardiac output?

organs wont be supplied with oxygen
poor perfusion
fatigued
lower temp
dizzy

By what mechanisms does the heart function?

Mechanical
Chemical
Electrical (SA, AV node, bundle of his, Purkije fibers)

What is the main electrolyte to be found in the heart?

Calcium

What happens during the "LUB" sound in the lub-dub of the heart?

S1
Closure of the mitral and tricuspid valves
Systole

What happens during the "DUB" sound in the lub-dub of the heart?

S2
Closure of the pulmonic and aortic valves.
Diastole

If you hear clicks in the heart what does that indicate?

Stenotic valves

What do an S3 or S4 indicate?

S3 - Ventricular Gallop (rapid passive filling of ventricles, normal
in athletes and young people or under 35)
S4 - Atrial Gallop (occurs when blood leaks into ventricles at
end diastolic volume (basically blood going into the ventricles when
it should have stopped) - hypertension, anemia and pulmonic stenosis,
ventricular hypertrophy and increasing age)
both seen in CHF

How does sympathetic stimulation influence CO?

HR is increased and releases catecholamines such as epinephrine and norepinephrine

How does excess Ca influence cardiac output?

Drops it

how does exercise influence cardiac output?

Increases it

How does sudden hypotension influence cardiac output?

Drops it

How does increased venous return influence cardiac output?

increases it

How does the parasympathetic stimulation influence cardiac output?

Drops it

how does bradycardia influence cardiac output?

Increases it

What is Starlings law?

amount of stretch determines force of contraction and amount of blood
ejected from a healthy left ventricle.

What history questions should you ask when talking to a patient?

Ask about -
chest pain/ MI/ Fatigue/ Palpations/ Dizziness/ Syncope/ Diet/
BMI/ drug use/ Smoking/ Meds/ Oral surgery/ Family hx/ edema/ SOB/
orthopnea/ Paroxysmal night time dyspnea/

What is a murmur?

turbulent blood flow through abnormal or normal valves
can occur in diastole or systole

What does it mean when you hear a bruits?

swishing sounds that may occur from turbulent blood flow in a
narrowed or atherosclerotic artery

What is a big early sign of Left sided heart failure?

Dyspnea on exertion

What S/S will you see with forward left sided heart failure?

1. Tiredness/fatigue
2. Decreased urine output
3. Irregular heartbeat/palpitations

In leftsided backward heart failure what happens?

The left side of the heart doesn't receive enough blood from the
lungs and it backs up or congests.
dyspnea on exertion
pulmonary edema
pink tinged sputum
symptoms get worse at night when you lay down
weight gain due to fluid retention

What are the S/S of right sided forward heart failure?

1. Weakness and fatigue due to increase of carbon dioxide
2. increased heart rate/palpitations

What are the S/S of backward right sided heart failure?

1. JVD
2. Edema (particularly lower extremities)
3. Weight gain due to extra fluid
4. increase in urination especially at night

Why is diastolic LHF EF normal?

the muscle contracts normally BUT the ventricles do NOT relax as they
should during ventricular filling.

What is high output heart failure?

When cardiac output remains normal but is caused by increased
metabolic needs or hyperkinetic conditons

What are some examples of increased metabolic needs or hyperkinetic
conditions than can cause high output failure?

septicemia
high fever
anemia
hyperthyroidism

What can cause right sided heart failure?

Usually pulmonary problems such as COPD, ARDS, or pulmonary hypertension.

why should you avoid NSAIDs in heart failure?

because they promote fluid retention

What is going on in cardiomyopathy that is dilated?

Enlarged dilated chambers of the heart due to weakened heart muscle

What is going on in cardiomyopathy that is hypertrophic?

The heart wall becomes thickened and not able to contract

What happens in restrictive cardiomyopathy?

When the walls of the Ventricles are too ridged to expand as they
fill with blood. The pumping ability may be normal but its harder for
them to get enough blood

What happens in arythromengic cardiomyopathy?

Right ventricle cardiomyopathy. fibrofatty replacement of the R. ventricle

What dental problems must be taken care of prior to valve replacement?

Dental caries
Periodontal disease

True or False. Patients with valve replacements are more likely to
have significant reductions in cardiac output. Especially those with
aortic stenosis or LVF from mitral valve disease.

TRUE

True or False. The tricuspid valve is commonly affected and may occur
following endocarditis in IV drug abusers.

False. It is rarely affected.

What is MVS and what causes it?

Mitral valve stenosis
usually caused by rheumatic carditis which causes valve thickening
and calcification

What can result from MSV?

prevents normal blood flow from L.A to L.V
L.A pressure rises and dilates the chamber
Pulmonary artery pressure rises
R. V hypertrophies
Pulmonary congestion and R. sided heart failure occur

what is mitral regurgitation?

Back flow of blood from L. V to L. A

True or false. Mitral valve prolapse is usually benign.

TRUE

What is the most common cardiac valve dysfunction?

Aortic stenosis

What happens in aortic stenosis?

The arortic valve opening narrows and obstructs L. V outflow causing hypertrophy

True or false. As stenosis worsens, cardiac output becomes more
flexible and can increase to meet the demands of the body during exertion.

False. It becomes fixed, not flexible and CANNOT increase.

What can cause aortic regurgitation?

The annulus (valve ring that attaches to the leaflets) may be dilated
or loose or deformed.

Aortic insufficiency can result from what?

infective endocarditis
congenital anatomic aortic valvular abnormalities
hypertension
marfan syndrome

How does amiodarone increase cardiac output?

causes BP to drop but strengthens the contraction (Digoxin works the
same way)