Heart and Vessels - Chapter 20

heart

A hollow, muscular organ that pumps blood throughout the body.muscular pump

cardiac muscle

Involuntary muscle tissue found only in the heart.

precordium

the area on the anterior chest directly overlying the heart and great vessels

superior vena cava

A vein that is the second largest vein in the human body and returns blood to the right atrium of the heart from the upper half of the body.

right pulmonary artery

takes blood from the right ventricle to the right lung

Flow of the heart

Right Atrium, Right Ventricle, Pulmonary Arteries, Lungs, Pulmonary Veins, Left Atrium, Left Ventricle, Aorta

pulmonary trunk

carries blood from right ventricle to pulmonary arteries

right atrium

the right upper chamber of the heart that receives blood from the venae cavae and coronary sinus

2nd-5th intercostal space and from the right border of the sternum to the left midclavicular line

Where is the heart located?

3

How many layers does the heart have?

pericardium

tough, fibrous, double-wall sac that surrounds and protects heart

myocardium

muscular wall of the heart; it does pumping

endocardium

thin layer of endothelial tissue that lines inner surface of heart chambers and valve

pulmonary circulation

flow of blood from the heart to the lungs and back to the heart

systemic circulation

circulation that supplies blood to all the body except to the lungs

4

How many valves in the heart?

atrioventricular valves

Valves located between the atrial and ventricular chambers on each side of the heart, prevent backflow into the atria when the ventricles are contracting.

tricuspid and mitral (bicuspid)

What are the 2 atrioventricular valve?

unidirectional (only open one way)(valves open and close passively in response to pressure gradients in moving blood)

What ways do valves flow?

down and to the left

Where does the apex of the heart point to?

top

Where does the base of the heart point to?

great vessels

lie bunched above the base of the heart

superior, inferior vena cava

return unoxygenated venous blood to the right side of the heart

pulmonary artery

leaves the right ventricle, bifurcates, and carries the venous blood to the lungs

pulmonary vein

return the freshly oxygenated blood to the left side of the heart and then aorta carries it out

aorta

carries the blood to the body- ascends from the left ventricle arches back at the level of the sternal angle and descends behind the heart

atrium

upper chamber of the heart- thin walled reservoir for holding blood

lungs

Where does the right side of the heart pump blood into?

body

Where does the left side of the heart pump blood into?

ventricle

muscular pumping chamber

prevent backflow of blood

What is the main purpose of the valve?

tricupsid

right AV valve

mitral

valve between the left atrium and the left ventricle.

diastole

Relaxation of the heart- AV valves open during the heart's filling phase

systole

pumping phase- AV valves close to prevent regurgitation of blood back up into the atria

semilunar valves

- set between the ventricles and the arteries- each valve has three cusps that look like half moons

pulmonic valve

right semilunar valve separating the right ventricle and pulmonary artery

aortic valve

The semilunar valve separating the aorta from the left ventricle that prevents blood from flowing back into the left ventricle.

pulmonary congestion

Abnormally high pressure in the left side gives a person?

distended neck veins, abdomen

Abnormally high pressure in the right side gives a person?

Left heart failure (signs and symptoms)

Pulmonary- SOB, dyspnea, orthopnea, DOE, pulmonary edema (auscultate: breath sounds crackles)

Right heart failure

Jugular Vein DistentionElevated CVPEdemaAscitesWeight Gain

direction of blood flow

The Right Atrium, receives "used blood" from the body. Blood will be pushed through the tricuspid valve to theRight Ventricle, the chamber which will pump to the lungs through the pulmonic valve to thePulmonary Arteries, providing blood to both lungs. Blood is circulated through the lungs where carbon dioxide is removed and oxygen added. It returns through thePulmonary Veins, which empty into theleft Atrium, a chamber which will push the Mitral Valve open. Blood then passes into theLeft Ventricle. As it pumps, the pressure will close the mitral valve and open the aortic valve, with blood passing through to theAorta, where it will be delivered to the rest of the body.

high to low

How does blood flow with the pressure gradients?

cardiac cycle

A complete heartbeat consisting of contraction and relaxation of both atria and both ventricles

diastole

Which is longer? diastole/ systole

atria (so the blood pours rapidly into the ventricles)

What has higher pressure? atria/ventricles

protodiastolic filling

Pressure in the atria is higher than that in the ventricles, so blood poors rapidly into the ventricles.- first passive filling phase/ early

presystole/atrial systole

atrial kick- toward the end of diastole the atria contract and push the last amount of blood (25% of the stroke volume) into the ventricles- it causes a small rise in left ventricular pressure- occurs during ventricular diastole

systole

Enough blood has been pumped into the ventricles so that ventricular pressure is finally higher than that in the atria- mitral and tricuspid swing shut- closure of the AV valves contributes to the first sound S1 and signals the beginning of systole- AV valves close to prevent any regurgitation of blood back up into the atria during contraction

isometric contraction

all 4 valves are closed- ventricular wall contract- contraction against a closed system works to build pressure insides the ventricles to high level(when the pressure in the ventricles finally exceeds pressure in the aorta, the aorta valve opens and blood is ejected rapidly)

s2

second heart sound, closure of semilunar valves- dub

s1

the first heart sound, heard when the atrioventricular (mitral and tricuspid) valves close

right side of the heart

- pressure in the right side of the heart are much lower than those of the left side because of less energy is needed to pump blood to its destination, the pulmonary circulation- these events occur slightly later in the right side because of the route of myocardial depolarization- as a result: 2 distinct components to each of the heart soundsfirst sound S1: M1 = mitral component closes just before tricuspidT1- tricuspid componentS2; aortic closure A2 heard slightly before pulmonic closure P2

first heart sound

S1- occurs with the closure of the AV valves and thus signals the beginning of systoleM1 slightly precedes T1 but you can usually hear these 2 components fused as one sound- loudest at apex

second heart sound

S2- occurs with closure of semilunar valves and signals the end of systolea2= aortic component of second sound slightly precedes pulmonic component p2- S2 loudest at base

effects of respiration

Volume of right and left ventricular systole is equal- MoRe to the Right heart- Less to the Leftmeaning during inspiration, intrathoracic pressure is decreased-pushes more blood into vena cava increasing venous return to the right side of the heart, increasing R ventricular stroke volume = prolongs R ventricular systole and delays pulmonic closureLeft side- greater amount of blood is sequestered in the lungs during inspiration- momentarily decreases amount returned to left side of the heart and aortic valve to close a bit earlier- two components can be heard = Split s2

split s2

When the aortic valve closes significantly earlier than the pulmonic valve, you can hear the two components separately

third heart sound

S3 ; Ventricular gallopVentricular filling creates vibrations over the chest; too much blood in ventricle at once- these vibrations are S3S3 occurs when the ventricles are resistant to filling during early rapid filling phase (protodiastole)- immediately occurs after s2, when the AV valves open and atrial blood first pours into the ventricles- S3 may be physiological or pathological- patients with heart failure and s3 often have a poor prognosisNatural occurrence in: athletes, children and pregnant women.Indicators of HF

heart sounds

-frequency/pitch; high or low (for low you need a stethoscope to hear)- intensity/loudness; loud or soft- duration: very short for heart sounds; silent periods are longer- timing: systole/diastole

fourth heart sound

s4: Atrial gallop- occurs at the end of diastole at the presystole when the ventricle is resistant to filling- can lead to ventricular hypertrophy- these atria contract and push blood into a noncompliant ventricle- creates s4- s4 occurs before s1- almost always pathological

murmurs

sounds created by abnormal, turbulent flow of blood in the heart- turbulent blood flow and collision currents- gentle, blowing, swooshing soundConditions resulting in murmurs1. velocity of blood increases (flow murmur; exercise; thyrotoxicosis2. viscosity of blood decreases (anemia)3. structural defects in valves (stenotic, narrowed valve, incompetent) or unusual openings occur in the chambers

automaticity

The ability of the heart to generate and conduct electrical impulses on its own.- contracts in response to an electrical current conveyed by a conduction system

SA node

What is the pacemaker of the heart?

sinoatrial node

specialized cells in the SA node near the superior vena cava initiates an electrical impulse- has an intrinsic rhythm

current flow

Orderly sequence1. Across the atria to the AV node low in the atrial septum2. It is delayed there slightly so the atria have time to contract before the ventricles are stimulated3. Then the impulse travels to the bundle of His, the right and left bundle branches, and then through the ventricles4. The electrical impulse stimulates the heart to do work and contract5. Small amount of electricity spreads to the body surface where it can be measured and recorded on the electrocardiograph (ECG)- then these are arbitrarily labeled PQRST on the ECG

P wave

depolarization of the atria (and SA node)

PR interval

From the beginning of the P wave to the beginning of the QRS complex (the time necessary for atrial depolarization plus the time for the impulse to travel through the AV nodes to the ventricles)

QRS complex

ventricular depolarization

depolarization

contraction

Repolarization

relaxation

T waves

ventricular repolarization

electrical (slightly before)

Which comes first in the heart? electrical/mechanical events?

4-6L (per min)

How much does the regular human heart pump out?

cardiac output

the volume of blood in each systole (stroke volume) x the number of beats per min (60 seconds)CO= SV x HR- the heart can alter its CO to meet metabolic needs of the body- preload and afterload increase the heart's ability to increase CO

preload

Volume in the ventricles at the end of diastole- the length to which the ventricular muscle is stretched at the end of diastole just before contractionWhen the blood returns to the ventricles, the muscle bundles are stretched past their normal resting state to accommodatethe force of the stretch is the preload

Frank-Starling Law

The greater the stretch, the stronger is the heart's contraction. This increased contractility results in an increased volume of blood ejected (Increased SV)

afterload

Pressure- the opposing pressure the ventricle must generate to open the aortic valve against the higher aortic pressure- resistance against which the ventricle must pump the blood- pressure is 5-10mmHG- to overcome the difference, the ventricular muscle tenses (isovolumic contraction)- after the aortic valve opens, rapid ejection occurs

neck vessels

carotid artery and jugular veins- efficacy of cardiac function

carotid artery

Central artery (close to the heart)- timing closely coincides with ventricular systole- located in groove between trachea and sternomastoid muscle, medial to and along-side that muscle

jugular veins

empty unoxygenated blood directly into the superior vena cava-usually not visible, although diffuse pulsations may be seen in sternal notch when person is supine-because no cardiac valve exists to separate superior vena cava from right atrium, jugular veins give info on the activity on the right side of the heart- specifically reflect filling pressure and volume changes- jugular veins expose this because volume and pressure increase when right side of the heart fails to pump efficiently

Older adult

-lifestyle affects aging process and risk for CVD- ability to heart to augment CO. with exercise is decreasedhemodynamic changes with aging- increased systolic BP- arteriosclerosis- left ventricular wall thickening- diastolic BP may decrease after the 5th decade- valves may thicken- pulse pressure widens- no change in resting HR or CO at rest- decreased ability of heart to pump at the needed rate for adequate circulation- dysrhythmia (supraventricular/ventricular) increase with age-ctopic beats are common in aging people - usually asymptomatic in healthy older people

Isolated systolic hypertension

a condition most commonly seen in the older adult in which the systolic pressure is greater than 140 mm Hg and the diastolic pressure is within normal limits (less than 90 mm Hg)

left ventricular wall thickening

adaptive mechanism to accommodate the vascular stiffening mentioned earlier that creates an increased workload on the heart- older adults and those with cardiac issues

arteriosclerosis

hardening of the arteries

Tachydysrhythmias

abnormally fast cardiac rhythms-not tolerated well in older adults- myocardium thicker and less complaint and early diastolic filling is impaired at rest- shortened diastole- may further compromise a vital organ whose function has been affected by aging/disease

increases

Incidence of coronary artery disease, hypertension, heart failure ____________ sharply with advancing age and accounts for

exercise

One of the best ways to reduce risk of CVD and respiratory illnesses for older adults?

cardiovascular disease

What is the most common underlying cause of death globally?

recommended favorable lifestyle (to reduce CVD risk)

no smoking, no obesity, physical activity at least once a week and a healthy diet

CVD risk factors

HTN- damages arterial system, increases HRSmoking: increasing oxygen demand on the heart while causing a decrease in oxygen supply, activation of platelets and changes in lipidsSerum cholesterol; LDLs add to lipid core of plaque formation in arteries which MI and strokePhysical activity: benefits effects on a HDL, vitamin D; 150 min/weeks of moderate-intensity aerobic activity, compared with noneSex and gender differences; women in CVD, claiming more lives than cancer, COPD, DMsubje

chest pain (subjective data)

Any chest pain or tightness?-Onset: when did it start?-How long have you had it? Have you had this pain before? How often?-Location: where did the pain start? does the pain radiate?-How would you describe it? crushing, stabbing, burning? clenching?- Is the pain brought on by activity?; rest, emotional, during sex, cold weather- Any associated symptoms: sweating, ashen gray, pale skin, heart skip beat, SOB, nausea, vomiting, racing of heart- Pain made worse by moving arms (MI) neck, breathing, lying flat- Pain relieved by rest or nitroglycerin? how many tablets?

angina

chest pain- occurs when the heart's own blood supply cannot keep up with metabolic demand.- can be pulmonary, musculoskeletal or GI in origin- squeezing "clenched fist" sign

dyspnea (subjective data)

Any shortness of breath?- which type of activity and how much brings on SOB?- DOE, paroxysmal, constant or intermittent, recumbentOnset: does SOB come on unexpectedly? does it come and go? lying down?- Awake you from sleep at night?- does SOB interfere with activities of daily liviing

recumbent

lying down

paroxysmal nocturnal dyspnea

Occurs with heart failure- lying down increases volume of intrathoracic blood and the weakened heart cannot accommodate the increased loaf- typically the person awakens after 2 hours of sleep with the perception of needing fresh air

orthopnea (subjective data)

How many pillows do you use when sleeping or lying down?-note the exact number of pillows used

cough (subjective data)

Do you have a cough?-duration: how long have you had it?-frequency: how long have you had it?-type: dry, hacking, barky, hoarse, or congested?\-do you cough up mucus? color? odor? blood tinged?\--- sputum production, mucoid, purulent- associated with activity, position (lying down), anxiety, talking- does activity makes it better or worse?- relieved by rest or medication

mitral stenosis

What disorders can cause hemoptysis?

fatigue (subjective data)

Do you seem to tire easily?- able to keep up with your family and coworkers(unusual fatigue is a top prodromal MI symptom for women)- when did it start? sudden/gradual?- has any recent change occurred in energy level- fatigue related to time of day; all of day, morning, evening\--- fatigue from decreased CO is worse in the evening, whereas fatigue from anxiety or depression occurs all day or is worse in the morning