Chapter 21 Cardiovascular System Flashcards
Functions of blood
- Transport of O2 & CO2 and nutrients
- Transport if hormones to target organs
- Transport of wastes to kidney/lungs
- Regulate blood pH and electrolyte composition
- defend against pathogens (wbcs)
- Restrict blood loss through injury sites
- Stabilizes body temp
Blood composition
plasma, plasma proteins, formed elements
Plasma
- 55%
- non-cellular fluid matrix
- water, electrolytes, nutrients, metabolic wastes
Plasma Proteins
transport hormones, lipids and is framework for clots
Platelets
cell-fragments that aid blood clotting
Anemia
- poor O2 delivery
- low #RBC’s= low hematocrit
Myocardium
- intercalary discs relay action potentials
- branched/meshwork
Endocardium
elastic & collagenous fibers
Membranes on heart
serous
Pericardial sac
- 2x layered membrane
- inner layer: parietal pericardium
- outer layer: parietal pleura
Cardiac Muscle
- single nucleus
- striated
- branched
Mediastinum
space btw lungs that contains esophagus, trachea, great vessels, NAVL’s, and heart
Pericardial Cavity
space btw parietal & visceral pericardia
Cardiac tamponade
pericardial cavity fills w/ blood and pressure builds up
Right Atrium
- coronary sinus
- pectinate muscles
- R. atrioventricular valve (tricuspid)
Right Ventricle
- R. atrioventricular valve (tricuspid)
- R. Pulmonary semilunar valve
- pulmonary trunk
- thin wall
Left Atrium
- 4 pulmonary veins
- pectinate muscles
- L atrioventricular valve (bicuspid)
Pectinate Muscles
on lateral wall of each auricle
Left Ventricle
- thick wall
- L. atrioventricular valve (bicuspid)
- L. aortic semilunar valve
- aorta
Papillary muscles
anchors chordae tendineae
Trabeculae Carneae
on ventricular walls and helps prevent sloshing
R. Atrioventricular Valve
tricuspid
L. Atrioventicular Valve
bicuspid
R. Semilunar Valve
pulmonary
L. Semilunar Valve
aortic
High BP, Low O2
Lung
High O2, Low BP
L. Ventricle
High BP, High O2
Body
Valves DON’T
actively open and close
Bad Seal?
back-flow (regurgitation)
Regurgitation
gurgling/fluttering sound= murmur
Most valve problems?
Atrioventricular valves
Mitral Valve prolapse
- failure of chords/papillary muscles to stabilize bicuspid valve
- valve goes into a different chamber
Systole
- contraction of the myocardium
- injects blood
Diastole
- relaxation of the myocardium
- blood flows
AV valves slam shut
lubb
Semilunar valves slam shut
dupp
Heart murmur
mechanical failure of a heart valve
Sino-atrial (SA) node
- medial wall of the right atrium
- pacemaker (nodal) cells are responsible for heart rate
Atrioventricular (AV) node
-connected to the SA-node
AV bundle (Bundle of His)
- runs from the AV-node through the inter-ventricular septum
- purkinje fibers branch then out into ventricular walls
Heart slowed:
parasympathetic ANS (acetylcholine)
Heart accelerated:
sympathetic ANS (norepinephrine)
Angina pectoris
referred pain associated with a heart attack
Embolus
drifting clot in the circulation
Embolism
blockage due to the clot
Coronary ischemia
restricted blood supply to myocardium
Myocardial infarction
localized cell death in myocardium
Infarction
tissue death due to blockage
Electrical flow
SA Node -> AV Node -> AV Bundle -> Purkinje fibers
Norepinephrine
accelerates
Acetylcholine
slows
First branches off of Aorta…
R&L coronary arteries
Right coronary artery
- anterior ventricular a.
- marginal a.
- posterior interventricular a.
Left coronary artery
- anterior interventricular a.
- circumflex branch
- left marginal a.
- posterior ventricular a.
Anterior side venous drainage
- great cardiac v.
- anterior cardiac v.
Posterior side venous drainage
- posterior cardiac v.
- middle cardiac v.
Coronary Sinus
- cardiac veins combine to form the coronary sinus
- drains to R. Atrium
