Adams: Anatomy and Physiology, the Heart

72 terms by Prinabubu 

Ready to study?
Start with Flashcards

Create a new folder

Advertisement Upgrade to remove ads

Functions, protective tissues, circulation pathways, vlaves, arteries, veins

Location of the Heart

a) Thoracic Cavity
b) Behind the mediastinum
c) Deep to sternum
d) Tilts 2/3 to left of mediastinum
e) Broader at the top: Base
f) Tapers to a blunt tip at the bottom of the left side: Apex
g) Size: 9-13 cm from (base-apex), 6cm thick, about the size of a fist
h) Weight: 300g
i) Averages 75 bpm, 3 million b/lifespan

Fibrous Skeleton

- collagen framework that gives support and shape to the heart
(1) Found through out
(2) Denser in some areas - in septum between chambers
(3) Hold valves open as heart beats
(4) Anchors myosites
(5) Provides elastic re-coil, prevents stretching during breathing
(6) Non-conductive (insulative) - prevents electrical overload

Protective Tissues

i) Skeletal system
ii) Sternum acts as protective plate
iii) Apex near 5th intercostal of the rib
iv) Under mediastinum there is fatty tissue that protects and insulates
v) Pericardium

Pericardium

membranous sac that encloses the heart and anchors via ligaments that attach to diaphragm, it protects and suspends
(i) Two Layers
1. Fibrous Pericardium
2. Serous Pericardium
a. Parietal Pericardium
b. Pericardial Cavity
c. Visceral Pericardium

Fibrous Pericardium

outer most layer made of Dense IR CT

Serous Pericardium

- 2nd inner layer to fibrous made of simple squamous epithelium
- serous membrane (2 layers)

Parietal Pericardium

outer most layer of the pericardium

Pericardial Cavity

lays between the parietal pericardium and the visceral pericardium and contains pericardial fluid- which is used to prevent friction

Visceral Pericardium

- aka Epicardium layer
- inner layer of pericardium and outer layer of myocardium
(1) made of simple squamous epithelium with overlay of Areolar CT, Adipose CT
(2) acts as shock absorber and emergency fuel supply
(3) contains Blood vessels - largest branches of the heart

Myocardium

muscle layer of the heart, responsible for contraction of the heart (pump)
(1) Thickest layer
(2) Composed of cardiac muscle tissue causing heart to beat in twisting motion

Endocardium

inner most layer of the heart, lines the valves and vessels of the heart.
(1) Composed Simple Squamous Epithelium with Areolar CT, NO Adipose CT
(2) Lines heart chambers and covers valves
(3) Directly continuous with Endothelium - lining of blood vessels
(4) Allows blood to move easily through the heart

Heart Walls

- from superficial to deep
Epicardium, visceral pericardium
Myocardium
Endocardium

Chambers of the Heart

i) Atria
ii) Ventricles

Atria

located posterior and superior
(1) receiving chambers
(2) blood enters from great veins
(3) contains auricles
(4) Contains Pectinate Muscles
(5) Right Atria:
(6) Left Atria:
(7) Left and Right Atria are separated by Inter-atrial Septum - made of collagenous CT.

Auricles

(flap-like extensions) - allows heart to increase in volume

Pectinate Muscles

large ridges located in pockets of septum, primarily used to contract muscles and force blood to the ventricles.

Right Atria (RA)

send De-oxygenized blood from Systemic Circulation to right ventricle

Left Atria (LA)

sends Oxygenated blood from Pulmonary vein and pumps into the left ventricle

Ventricles

located anterior and inferior
(1) Pumping chambers that eject blood
(2) Maintain circulation by taking blood into other areas
(3) Contains Trabeculae Carneae:
(4) Right Ventricle:
(5) Left Ventricle:
(a) 2-4x thicker and pushes blood through the systemic circulation
(6) Right and Left Ventricle are divided by the Interventricular Septum

Trabeculae Carneae

internal muscle, "meaty ridges", thick and strong

Left Ventricle (LV)

located inferior, largest portion, hardest working tissue

Right Ventricle (RV)

pumps blood to lungs

Atrioventricular Septum

separates the atrium from the ventricles.

Sulcus

groove on the surface of the heart that contains blood vessels and adipose CT.
(1) Coronary Sulcus:
(2) Anterior Interventricular Sulcus
(3) Posterior Interventricular Sulcus

Coronary Sulcus

aka Atrioventricular Sulcus, groove that marks the boundary between atrium and the ventricles, holds the right coronary artery

Anterior Interventricular Sulcus

extends inferiorly from coronary sulcus on the anterior surface of the heart, divides the rt and left ventricle, usually holds the great cardiac vein

Posterior Interventricular Sulcus

extends inferiorly from the coronary sulcus on the posterior surface of the heart, usually holds the posterior interventricular artery

Superior and Inferior Vena Cava

carry blood from the body to the right atrium

Pulmonary Veins

carry blood from the lungs to the left atrium.

Aorta

sends blood out of the left ventricle to the rest of the body.

Pulmonary Arteries

carry blood to the lungs

Heart Valves

i) Makes blood flow in 1 direction controlled by pressure gradient, preventing back flow
ii) Guarded openings between chambers and heart arteries
iii) 2-3 cusps/leaflets - curved fibrous CT with endothelium opens and closes to allow blood to move
iv) Atrioventricular Valve (AV Valve):
(1) Tricuspid Valve
(2) Bicuspid Valve or Mitral Valve:
v) Each ventricle contains papillary muscles
vi) Muscles are connected to Chordae Tendineae -

Atrioventricular Valve (AV)

located between each atrium and its ventricle

Tricuspid Valve

located between the right atrium and the right ventricle, has three cusps.

Mitral or Bicuspid Valve

located between the left atrium and the left ventricle, has two cusps.

Papillary Muscles

cone shaped muscular pillars in each ventricle that assist in the opening and closing of the valves

Chordae Tendineae

thin strong connective tissue strings to free margins of the cusps of AV valves. Used to protect against back flow.

Circulation of the Blood

i) Occurs at 75bpm which takes about a minute to complete
ii) Blood circulates in continuous loops
iii) Pulmonary Circuit
iv) Systemic Circuit:
v) Coronary Circulation

Pulmonary Circuit

contains Deoxy Blood and lots of CO2
(1) Arteries carry de-oxy blood to other areas of the heart, veins carry oxy blood to the heart
(2) Rt. Atrium contracts blood passes through RT AV valve into Rt. Ventricle
(3) Pumps blood through pulmonary valve into pulmonary trunk
(4) Blood travels to the rt and left pulmonary arteries
(5) That carries into both lungs
(6) Then they branch into a series of small arteries into pulmonary capillaries
(7) A gas exchange occurs where blood loads up O2 and dumps CO2
(8) Blood will drain and move into Rt and Left Pulmonary veins that travels to the heart
(9) Oxygenated Blood is emptied into left atrium

Systemic Circuit

contains Oxgenated Blood and almost no CO2
(1) Arteries carry oxy away from the heart, veins carry de-oxy blood to the heart
(2) from left atrium, Oxy blood passes through left AV valve into left ventricle
(3) oxy blood passes through aortic valve into ascending aorta to aortic arch
(4) then it distributes into systemic arteries that spread and branch to systemic capillaries where it will unload O2 and load CO2
(5) Deoxy blood will collect into systemic veins, converge onto superior and inferior vena cava
(6) Returns to heart and empties into the rt. atrium

Coronary Circuit

heart's own circulation system that supplies its own blood for nutrients
(1) Each body had slightly different arrangements of arteries and veins

Arteries in the Coronary Circuit

(2) Two coronary arteries originate at the aorta
(a) Left Coronary Artery (LCA):
(b) Rt Coronary Artery (RCA):

Left Coronary Artery (LCA)

on left side of aorta, supply blood to left atrium, most of the left ventricle, and part of right anterior ventricle.
(i) Anterior Ventricular Artery:
(ii) Circumflex artery:

Right Coronary Artery (RCA)

originates on the rt side of the aorta, extends to coronary sulcus to the right posteriorly, supply the right atrium, most of the right ventricle, and part of the left posterior ventricle
(i) Right Marginal Artery:
(ii) Posterior Interventricular Artery:Po
(iii) SinoAtriol Branch:

Anterior Ventricular Artery

lies in the anterior interventricular sulcus

Circumflex Artery

extends around the coronary sulcus on the left to posterior surface of the heart.

Sinoatrial branch

sends blood to Sinoatrial node - pacemaker of the heart

Posterior Interventricular Artery

located in posterior interventricular sulcus, sends blood to poster walls of ventricles and to interventricular septum, join with anterior interventricular artery, which is branch with Circumflex artery.

Right Marginal Artery

runs toward apex to later rt. Atrium and rt. Ventricle and links with

Cardiac Veins

drain blood from the cardiac muscle, pathways are parallel to the coronary arteries, and most drain into the coronary sinus - a large vein located within the coronary sulcus on the posterior aspect that drain into the right atrium along with some other cardiac veins.
(a) All the coronary veins runs parallel to the coronary sinus. Names are really similar.
(b) Thebesian Veins:
(c) Great Cardiac Vein:
(d) Small Cardiac Vein:
(e) Middle Cardiac Vein:
(f) Left Marginal Vein.
(g) Multiple pathways ensures the heart maintains motion.

Thebesian Veins

small veins that directly drain by diffusion into the rt. Atrium and rt. Ventricle (20%) originate from myocardium near the rt. and lft atrium.

Great Cardiac Vein

drains from anterior aspect, runs along the anterior IV sulcus with the ant. IV artery

Small Cardiac Vein

drains from posterior aspect, located near the rt. ventricle.

Middle Cardiac Vein

runs along posterior IV sulcus and drains blood posteriorly, located along the Posterior IV sulcus with the Post. IV artery

Left Marginal Vein

drains blood to apex, runs parallel to left marginal artery that is extended from the circumflex artery

Anastomoses

Blood empties from artery to artery or vein to vein respectively

Pericarditis

inflammation of pericardium.
(1) Sensations of pain when the heart rubs against the pericardium as the heart beats.
(2) Due to lack of pericardial fluid

Valvular Insufficiences/ Valvular Incompetence

(1) Valvular Stenosis:
(2) Valvular Prolapse:
(d) Mitral Valve Prolapse (MVP)

Valvular Stenosis

valves stiffen by scar tissue resulting from a heart attack

Valvular Prolapse

valve turns inside out
(a) Movement is in opposite direction
(b) Works harder, gets larger, which make it inflexible
(c) Overtime, can result in fatigue, shortness of breath, Ischemia: chest pain, heart failure.

Mitral Valve Prolapse (MVP)

commonly symptom is Heart murmur due to turbulence of back flow.
(3) Can be corrected through valvular replacement

Angina Pectoris

occurs when there is 75% of blockage
(a) sense of heaviness and pain in chest
(b) temporary ischemia
(c) may rely on anaerobic respiration for metabolism
(d) Myocardial Infarction may result
(v) blockage due to Atherosclerosis:
(vi) Collateral Circulation: alternate pathways
(vii) Hypercholesterolemia
(e) Blockage of artery is impossible to fix to naturally, therefore prevention is the key but changing your diet and exercise will allow your body to increase the blockage.

Myocardial Infarction

total blockage of artery
(i) Aka Heart Attack
(ii) Begins when atheroma totally blocks coronary blood vessel
(iii) Any tissue not receiving blood will die within 3min
(iv) Fibrillation: rapid fluttery contractions
1. Cardiac arrest follows: heart stops beating
a. Stops blood supply to the brain within 4-7 min. will cause death

Atherosclerosis

build up of plaque (LDL and Sat. fats) on the interior walls of arteries

Hypercholesterolemia

genetic condition where the body retains cholesterol

Prevention of Angina Pectoris

(i) Prevention: exercise and change of diet
1. Eating HDL (high density Lipoproteins) will regulate LDL's and bind them in the blood stream
2. Increase soluble fiber which are brans, whole grain, apples, beans will lower LDL's
3. Omega-3 unsaturated fatty acids (PUFAS) will lower LDL and reduce arterial thickness commonly found in fatty fishes

Surgical Remedies of Angina Pectoris

1. Angioplasty: surgical procedure to widen narrow Blood vessels
a. Balloon Angioplasty
b. Laser Angioplasty:

Balloon Angioplasty

catheter is placed in bloackage, a ballon inflates in the blood vessel will open and a stent is placed to keep the artery open.
i. Drawbacks
ii. Thrombosis: blood clot, embellism may result.
iv. Resonosis may occur - plaque regrowth.

Laser Angioplasty

catheter enters and the laser burns the arterial plaque,
i. Downsides
ii. Plaque may break off and cause a heart attack
iii. It may damage arterial walls
iv. Resonosis may occur - plaque regrowth.

Coronary Bypass Surgery

cut section of the artery from somewhere else and detour it to shift the flow of blood.

Systole

action of heart beat

Diastole

relaxation of heart beat, results in receiving more blood in coronary artery

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set