CARDIO ANA/PHY/ECG Flashcards
The period wherein the atria contracts and forces more blood into the ventricles
Active ventricular filling
Which node generates an action potential that stimulates atrial contraction and begins the cardiac cycle?
Sinus node
What is stimulated when an action potential passes down the AV node, down the AV bundle and Purkinje fibers?
Ventricular systole
What valve/s close/s when the ventricular pressures increase and blood flows toward the atria?
Atrioventricular valves (tricuspid, mitral)
What heart sound is produced during the turbulent blood into the ventricles?
S3
Depolarization is caused by the movement of what chemical compounds?
Na+ (sodium)
What causes the ventricles to contract and prevent the valves from opening? What connective tissue attached to the valve cusps do they pull on?
Papillary muscle
Chordae tendinae
They are identified by the great artery in which they’re located
Semilunar valves (Pulmonic, aortic)
Process of depolarization (which gates open and close)
Na+ channels open, K+ channels close
Increased venous return results in \
I. Increases EDV
II. Increases preload
III. Decreases EDV
IV. Decreases preload
I & II
Formula for cardiac output
SV x HR
What is the degree of tension on the muscle when it begins to contract?
Preload
What is the load against which the muscle exerts its contractile force?
Afterload
What direction is the apex pointed in? (3)
Anterior, inferior, to the left
Point wherein the contraction of the apex is most pronounced?
Point of maximum impulse (PMI)
What do you call the lubricant between the layers of the serous pericardium?
Pericardial fluid
When there’s too much pericardial fluid, what happens? Too little?
Decreased - + pericardial friction rub = pericarditis
Increased - cardiac tamponade = cardiac arrest
What are the 2 layers of the serous pericardium? Differentiate
Visceral pericardium - epicardium
- adheres to the heart
Parietal - outermost layer
Primary function of the AV valves?
Prevent backflow of blood into the atria during ventricular contraction
What fills the ventricles with blood from atria during diastole?
AV valves (tricuspid, mitral)
Volume of blood ejected with each myocardial contraction
Stroke volume
Volume of blood ejected per minute
Cardiac output
phases during ECG (3)
P wave - atrial depo
QRS complex - ventricular depo
T wave - ventricular repo
Initiation of ventricular repolarization?
ST segment
Valve from RA to RV
tricuspid
Valve that carries oxygenated blood from LA to LV
mitral
If SV increases, what happened to preload and after load?
SV increases when
- Preload increases
- afterload decreases
AKA visceral pericardium
epicardium
Describe S1 (3)
longer, loud, low in pitch
Describe S2 (3)
shorter, lower in volume, higher in pitch
heart sound during passive ventricular filling when blood flows turbulently into the ventricles
S3
The extent to which the ventricular walls are stretched?
Preload
What happens during Phase 2 of the cardiac cycle? What is it called?
Plateau
- Calcium channels stay open
- potassium channels close
Bundle of His give rise to which part of the conducting system?
Purkinje fibers
What forms the apex of the heart
LV
What opening is present in the fetal heart? It eventually develops into a flat depression which is called?
Foramen Ovale -> Fossa Ovalis
Break down the descending aorta
Descending aorta
Thoracic aorta
Abdominal Aorta
Common iliac artery
1. internal CIA - hypogastric (pelvis, buttocks, genitals)
2. external CIA
- femoral
- popliteal
- tibial
Break down the ascending aorta
Ascending aorta
Arch of aorta
Brachiocephalic
1. Common carotid artery
- int. CCA -> ACA, MCA
- ext. CCA -> superficial structures, ends at TMJ
2. subclavian
- axillary -> brachial -> radial, ulnar
- vertebral -> basilar -> PCA
What happens when ventricular pressure drops below atrial pressure?
AV valves open, ventricular filling starts
Large diameter fibers that conduct the action potential from the apex to the ventricles
Purkinje fibers
AKA sternocostal surface of the heart. what parts of the heart are part of this surface?
anterior
RA, RV -> mainly RV
AKA diaphragmatic surface of the heart. what parts of the heart are part of this surface?
inferior
RV, LV -> mainly LV
AKA posterior surface of the heart. what parts of the heart are part of this surface?
base
RA, LA -> mainly LA
Small volume of blood that is not ejected during systole?
ESV (end systolic volume)
