ekg chapter 1 anatomy and physiology

Where is the location of the heart

Mediastinum ( in between the chest )

How much of the heart is left of the midline

2/3

Between what ribs does the heart lie

Between 2nd and 6th

How big is a heart in a adult

Roughly the size of fist

What influences the size and weight of the heart

Age, body weight and build, physical activity frequency, heart disease

What are the surfaces of the heart

Anterior , inferior, posterior (base), apex

What part of the heart is in the anterior surface

Ight ventricle

What makes up the inferior surface

Mostly of the left ventricle

What makes up the base of the heart

Upper portion of the heart, left atrium, small portion of right atrium, proximal portions of the superior and inferior vena cava and pulmonary veins

What forms the apex of the heart

The left ventricle

What location of the heart do you listen for the heart rate

The apex

What are the coverings of the heart

Pericardium, partial pericardium, serous pericardium, pencardium space

What is the pericardium

Double wall sac that enclose the heart and helps protect it from trauma

Pericardial space

Lubricant, preventing friction as the heart beats

What sound can you hear when here is no fluid in the pericardial space

Sand paper sound

What are the layers of the heart

Endocardium, myocardium, epicardium

What is the inner most layer of the heart

Endocardium

What layer of the heart lines the heart chamber

Endocardium

What layer of the heart continues to the layers of vessels

Endocardium

What layer of the heart is the middle layer

Myocardium

What layer of the heart is thick and muscular

Myocardium

What layer of the heart is responsible for pumping action

Myocardium because its the muscular layer

Now many chamber does the heart have

4 chambers

How many upper chambers does the heart have and what are they

Two: right and left atrium

How many lower chambers of the heart are there and what are they

Two: right and left ventricles

What are the two types of heart valves

Atrioventricular valves (AV) and semilunar valves (Sv)

What are the two functions of the heart valves

1. Ensures blood flows in one direction through the chambers

2. Prevents back flow of blood

Function of atrioventricular values

Separates atrium and ventricles

What are the two atrioventricular values

Tricuspid value and mitral valve (bicuspid)

Location of tricuspid valve

Between right atrium and right ventricle

Location of mitral valve

Between left atrium and left ventricle

What makes the sound for heart rate

The valves closing

What are the two semilunar valves ( sv)

1. Pulmonary valve 2. Aortic valve

Function of semilunar valves ( sv)

Prevent back flow of blood from aorta and pulmonary arteries into ventricles

What are the coronary arteries

1. Right coronary artery (RCA)

2. Left coronary artery ( LCA )

3. Left anterior descending artery (LAD)

4. Circumflex artery(CX)

What does the right coronary artery (RCA) supply

1. right atrium

2. Right ventricle

3. Inferior surface of the left ventricle in about 85% of individuals

4. Posterior surface of the left ventricles about 85% of individuals

5. Sinoartial (SA) node

6. Av bundle 85% to 90%

What is the first segment of the left coronary artery

The left main

What does the left coronary artery (LCA) supply

Supplies oxygenated blood to its primary branches : Left anterior descending (LAD), and the circumflex (cx)

Location of the Left anterior descending artery (LAD)

Lies on the outer surface (epicardial) on the front of the heart

What is called the widow maker

Occlusion of the left main

Why is it called the widow maker

Associated with the sudden cardiac arrest when the left main is blocked

Location of the circumflex artery

Circles around the left side of the heart in a groove on the back that separates the left attribute and the left ventricle called the coronary sulcus

Acute coronary syndrome

Condition caused by a similar sequence of pathological events involving reduced coronary artery blood flow

What does acute coronary syndrome result in

Myocardial ischemia or injury to death of heart muscle

What is myocardial ischemia

Lack of oxygenated blood flow to heart resulting in tissue death

When does arteriosclerosis occur

Day your born

What is arteriosclerosis

Disease of atrial system that thickens and hardens the vessel walls

When does artheosclerosis occur

With bad diet and lack of exercise

Is arteriosclerosis reversible

Yes with better diet and exercise

What is artheriosclerosis

A form of atriosclerosis ( hardening and thickening of vessel walls) from build up of fat

Angina lector is

Chest discomfort or other related symptoms

What causes angina pectoral

1. Myocardial ischemia

2. No clinical symptoms (silent ischemia )

3. Heart attack

4. Sudden death

What are the primary neurotransmitters of the sympathetic system

Norepinephrine and epinephrine

What is myocardial infarction and why does it happen

Heart attack.

From clogged arteries

How does Cardiac arrest happen

Electrical issue

What response is the sympathetic system

Fight or flight

What is alpha 1 and what happens and why

It is a periferal vaso constriction and blood is sent to the heart and lungs and constricts blood to the eyes, blood vessels, bladder, male reproductive organs to get us out of danger

What is beta 2 what Happens and why

Bronchial smooth muscle dialation so we can take in more oxygen to get us out of danger

What are the primary neurotransmitters of the parasympathetic system

Acetylcholine

Main affect of the parasympathetic system

Slows heart rate down when we’re out of danger

What response is the parasympathetic system

Rest and digest

Barorecptors structure and location

Specialized nerve tissue found in corotoid arteries and aortic arch

Barorecptors fiction

Detects changes in blood pressure

What happens when Barorecptors are stimulated

Cause a reflex response in sympathetic system or parasympathetic system

Chemoreceptors location

In the internal carotid arteries and aortic arch

Chemoreceptors function

Detects and responds to changes in the concentration of hydrogen ions( PH, oxygen, carbon dioxide of the blood)

Chronotropic effect

Change in heart rate

Positive chronotropic effect

Increase of heart rate

Negative chronotropic effect

Decrease of heart rate

Inotropic effect

Change in myocardial contractility

Positive inotropic effect

Increase in myocardial contractility

Negatice inotropic effect

Decrease in myocardial contractility

Dromotropic effect

Change in speed of impulse conduction the conduction system

Pulmonary circulation

Right if the heart pumps unoxygenated blood from body too the lungs

Systemic circulation

Left side of the heart receives oxygenated blood from lungs and pumps it out to the rest of the body

Cardiac cycle periods

Systole and diastole

Systole period of cardiac cycle

Period during which chamber is contracting and blood is being ejected

Diastole period of cardiac cycle

Period of relaxation during which chamber is filling

Atrial diastole process

• blood enters the right atrium

• Right atrium fills and descends

• Tricuspid valve opens

• Right ventricle fills

• Left atrium receives blood from pulmonary veins

• Mitral valve opens and left atrium fills

• Blood flows to left ventricle

Atrial systole

Atrial kick

Atrial kick

Allows the extra blood to ventricles( to fill completely)because we don’t want any left over

Ventricle systole

Blood is propelled through systemic and pulmonary circulation

SL valves close

Ventricular diastole

Ventricles begin to passively fill with blood

Blood pressure

Forces exerted by circulating blood volume on walls and arteries

Blood pressure formula

Bo= cardiac output x peripheral resistance

Cardiac output

Amount of blood pumped into the aorta each minute by the left ventricle

Factors that determine cardiac output

• HR

• Myocardial contractility

• Preload

• After load

Ejection fraction

Percentage of blood pumped out of the ventricle with each contraction

What is ejection fraction used for

Measure of the ventricular function

Normal ejection fraction rates

50% to 65%

Stroke volume

The amount of blood ejected from the left ventricle with each heartbeat.

How is stroke volume determined

• degree of ventricular filling when the heart is relaxed(preload)

• The pressure against when the ventricular must pump(afterload)

• The myocardium’s contractile state(contracting or relaxing)

What is preload also known as

End-diastole volume

What is preload

The force exerted by the walls of the ventricle at the ends of diastole

What influences preload

The volume of blood returning to the heart(venous return)

Afterload

The pressure response against which the ventricles must pump to eject blood

What influences afterload

• arterial blood pressure

• Ability of arteries to become stretched

• Arterial resistance

Cardiac output

The amount of blood pumped into the aorta each minute by the left ventricle

Signs and symptoms of decreased cardiac output

• acute drop in blood pressure

• Acute changes in mental status

• Cold clammy skin

• Color changes in skin

• Crackles

• Dyspnea

• Dysrhythmias

• Fatigue

• Orthopnea

• Restlessnsss

Atria purpose

Receives blood and is holding tankers for blood for the ventricles