The Cardiovascular System

A closed system of the heart and blood vessels

The heart ______blood

Blood vessels allow blood to ______to all parts of the body

The function of the cardiovascular system is to deliver ______and ______and to remove ______and other waste products

11.1.1 Describe the location of the heart in the body and identify its major anatomical areas on an appropriate model or diagram.

The Heart

Location

Thorax between the ______

Pointed apex directed toward ______

About the size of your fist

Less than ______

Coverings

Pericardium – a ______serous membrane

  • Visceral pericardium
  • Next to heart
  • Parietal pericardium
  • ______layer

______fluid fills the space between the layers of pericardium

Heart Wall

Three layers

  • ______
  • Outside layer
  • This layer is the parietal pericardium
  • Connective tissue layer
  • ______
  • Middle layer
  • Mostly cardiac muscle
  • ______
  • Inner layer
  • Endothelium

Chambers

Right and left side act as separate pumps

Four chambers

  • ______
  • ______chambers

Right atrium

Left atrium

  • ______
  • Discharging chambers

Right ventricle

Left ventricle

11.1.3Explain the operation of the heart valves.

Valves

Allow blood to flow in only ______direction

Four valves

  • Atrioventricular valves – between ______and ventricles
  • Bicuspid valve (left)
  • ______valve (right)
  • Semilunar valves between ventricle and ______
  • ______semilunar valve
  • Aortic semilunar valve

Valves ______as blood is pumped through

Held in place by chordae ______(“heart strings”)

Close to prevent ______

Valve Pathology

  • Incompetent valve = backflow and ______
  • Stenosis = stiff= heart workload increased
  • May be replaced by ______
  • Lup Dub Heart Sound

Associated Great Vessels

Aorta

  • Leaves left ventricle

______arteries

  • Leave right ventricle

______

  • Enters right atrium

Pulmonary veins (four)

  • Enter left ______

11.1.4Name the functional blood supply of the heart.

Coronary Circulation

  • Blood in the heart chambers does not nourish the ______
  • The heart has its own nourishing ______system
  • Coronary arteries
  • Cardiac veins
  • Blood empties into the ______via the coronary sinus

Cardiac Pathology

  • Rapid heart beat
  • = Inadequate blood
  • = Angina Pectoris

Physiology of the Heart

Body has 6 quarts of blood

1000 times a day

6000 quarts a day

11.2.1Name the elements of the intrinsic conduction system of the heart and describe the pathway of impulses through this system

Conduction System

Cardiac muscle contract ______and independently, even if nerves are severed.

Different areas of the heart have different rhythms.

Atrial – about 60/min

Ventricular – about ______

A controlling system is needed

Autonomic nervous system

______system (nodal system)

Intrinsic conduction system (nodal system)

Composed of a special tissue found nowwhere else

Cross between ______and ______

Causes heart to depolarize and a contraction rate (≈75/min)

  • Special tissue sets the pace
  • ______(SA) node (right atrium)

Pacemaker

  • Atrioventricular(AV) node (junction of r&l atria and ventricles)
  • Atrioventricular______(Bundle of His)
  • Bundle branches (right and left)
  • ______fibers

1)Depolarization starts in the SA node

2)Impulse spreads through the ______to the AV node, causing the atria to ______.

3)At AV node, impulse is ______.

4)Gives atria time to finish contracting.

5)Then impulse passes rapidly through the AV bundle, bundle branches and Purkinje fibers.

6)This “______” the heart

7)Blood ejects blood into arteries.

Atria and ventricles are separated by “______” connective tissue

Depolarization waves can reach the ventricles only through the AV node.

11.2.4Explain what information can be gained from an electrocardiogram.

Electrocardiograms (EKG/ECG)

Three formations

P wave: impulse across atria

QRS complex: spread of impulse down septum, around ventricles in Purkinje fibers

T wave: end of electrical activity in ventricles

Electrocardiogram(ECG/EKG)

Atria contract ______

Atria relax, then ventricles contract

Systole = ______

Diastole = relaxation

The terms systole and diastole refer to the contraction and relaxation of the ______.

______– refers to the events of one complete heartbeat.

Both the atria and ventricles must contract and relax.

This happens in about ______second.

11.2.3 Define heart sounds and murmur.

Sounds of the heart

“lub” - “dub” – pause -“lub” - “dub” – pause

lub – closing of the ______valves

Louder and longer

dub – closing of the ______valves

Softer and shorter

Murmurs – abnormal or unusual heart sounds

Normally blood flow is ______

Caused by incompetent valves

Pathology of the Heart

Damage to AV node = release of ventricles from control = slower heart beat

Slower heart beat can lead to ______

  • Fibrillation is the rapid uncoordinated ______of the heart muscle.
  • Fibrillation = lack of blood flow to the heart

Tachycardia = more than 100 beats/min

Bradychardia = less than 60 beats/min

11.2.5Describe the effect of an increased and decreased heart rate including CHF.

Cardiac output

CO = HR x SV

______ml/min = 75 beats/min x 70 mls/beat

Norm = 5000 ml/min

Entire blood supply passes through body once per ______.

CO varies with demands of the body.

Regulation of Heart

Stroke volume usually remains relatively ______

Starling’s law of the heart – the more that the cardiac muscle is stretched, the stronger the contraction

Changing heart rate is the most common way to change cardiac output

Increased heart rate

Sympathetic nervous system

  • ______
  • Low blood pressure

Hormones

  • ______
  • Thyroxine

Exercise

Decreased blood volume

Decreased heart rate

Parasympathetic nervous system

______blood pressure or blood volume

Dereased venous return

In Congestive Heart Failure the heart is ______and pumps weakly. Digitalis works to provide a slow, steady, but stronger beat.

Congestive Heart Failure (CHF)

Decline in pumping ______of heart

Inadequate circulation

Is a progressive high blood pressure and history of multiple Myocardial Infarctions

  • Caused by atherosclerosis ( ______of the coronary vessels with fatty build up.

Left side fails = pulmonary congestion and suffocation

Right side fails = ______congestion and edema

Physiology of Circulation

11.3.2Define blood pressure and pulse and name several pulse points.

Vital Signs

______pulse

Blood pressure

______Rate

Body Temperature

All indicate the efficiency of the system

Pulse

______wave of blood

Alternating expansion and recoil of an artery that occurs with each beat of the left ______.

Around 73 beats per minute

Monitored at “______” where pulse is easily palpated

These pressure points can be used to help stop ______.

11.3.3List factors affecting and/or determining blood pressure.

Blood Pressure

The pressure the ______exerts against the inner walls of the blood vessels .

Keeps blood circulating ______even between heartbeats.

Highest in large arteries/lowest in the venae cavae.

If vein is cut blood flow is ______

If artery is cut blood flow would squirt .

Measurements by health professionals are made on the pressure in large arteries

______– pressure at the peak of ventricular contraction

______– pressure when ventricles relax

Pressure in blood vessels ______as the distance away from the heart increases

Measured in mm Hg

Measuring Arterial Blood Pressure

Ausultatory Method

BP: Effects of Factors

BP is directly related to cardiac output and ______.

Peripheral resistance – the amount of ______encountered by the blood as it flows through the blood vessels.

Most important factor is the ______or narrowing of blood vessels.

Blood volume and viscosity raises periheral resistance.

Others: age, weight, time of day , exercise, body position, emotional state, drugs.

11.3.3List factors affecting and/or determining blood pressure.

Factors on BP

1)Neural factors

Autonomic nervous system adjustments (sympathetic division)

Causes ______– narrowing of the blood vessels, which increases the blood pressure.

Examples: standing up, hemorrhaging, exercise or frightened

Never causes vasoconstriction of ______or______vessels.

2) Renal factors: the kidneys

Regulation by altering blood volume

  • BP ______= water leaves body through urine.

______– hormonal control, a vasoconstrictor chemical

3) Temperature

Heat has a vaso______effect

  • Warm compresses for inflamed areas

Cold has a vaso______effect

  • Cold packs for swelling bruises

4) Chemicals

Various substances can cause increases or decrease

  • Epinephrine, Nicotine - ______
  • Alcohol, Histamine - ______

5) Diet - Opinions always changing

Overall excepted – salt, saturated fats, cholesterol prevent ______.

11.3.4Define hypertension and atherosclerosis and describe possible health consequences of these conditions.

Variations in Blood Pressure

Human normal range is variable

Normal

  • ______mm Hg systolic
  • ______mm Hg diastolic

Hypotension – overall viewed as a good thing

  • Low systolic (below 110 mm HG)
  • Often associated with illness or poor ______

Hypertension- High systolic (above 140 mm HG)

  • Can be dangerous if it is chronic
  • Linked to diet, ______, heredity, race, stress