Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
29 Cards in this Set
- Front
- Back
|
What are the two layers of the pericardium?
|
Parietal pericardium: outer layer forms inner layer of pericardial sac
Visceral pericardium: inner layer of pericardium |
|
|
What are the sulci?
|
Coronary sulcus:
divides atria and ventricles Anterior and posterior interventricular sulci: separate left and right ventricles contain blood vessels of cardiac muscle |
|
|
What are the three layers of the heart wall?
|
Epicardium: outer layer
Myocardium: middle layer Endocardium: inner layer |
|
|
What is the epicardium?
|
Visceral pericardium
Covers the heart |
|
|
What is the myocardium?
|
Muscular wall of the heart
Concentric layers of cardiac muscle tissue Atrial myocardium wraps around great vessels 2 divisions of ventricular myocardium |
|
|
What is the purpose of the intercalated discs?
|
interconnect cardiac muscle cells
secured by desmosomes linked by gap junctions convey force of contraction propagate action potentials |
|
|
What are four characteristics of cardiac muscle cells?
|
Small size
Single, central nucleus Branching interconnections between cells Intercalated discs |
|
|
What is the foramen ovule?
|
Before birth, is an opening through interatrial septum
Connects the 2 atria Seals off at birth, forming fossa ovalis |
|
|
What are the pectinate muscles?
|
Contain prominent muscular ridges
On anterior atrial wall And inner surfaces of right auricle |
|
|
What do the chordae tendineae do?
|
Prevent backflow of blood by preventing valves from flipping in
Connected to papillary muscles |
|
|
What is regurgitation?
|
Failure of valves, causes backflow of blood into atria
|
|
|
What are the aortic sinuses?
|
At base of ascending aorta
Prevent valve cusps from sticking to aorta Origin of right and left coronary arteries |
|
|
Where do the coronary arteries originate?
|
Aortic sinuses
|
|
|
Where does the right coronary artery supply blood to?
|
right atrium
portions of both ventricles cells of sinoatrial (SA) and atrioventricular nodes marginal arteries (surface of right ventricle) posterior interventricular artery |
|
|
Where does the left coronary artery supply blood to?
|
left ventricle
left atrium interventricular septum 2 main branches: circumflex artery anterior interventricular artery |
|
|
What are anastomoses?
|
Interconnect vessicles to stabalize blood supply by creating multiple pathways to tissues
|
|
|
What are the two types of cardiac muscle cells?
|
Conducting system: controls and coordinates heartbeat
Contractile cells: produce contractions |
|
|
What are some abdormal pacemaker functions?
|
Bradycardia: abnormally slow heart rate
Tachycardia: abnormally fast heart rate Cardiac Arrhythmias: Abnormal patterns of cardiac electrical activity |
|
|
What is an ectopic pacemaker?
|
Abnormal cells
Generate high rate of action potentials Bypass conducting system Disrupt ventricular contractions |
|
|
ECG Stuff:
|
P wave: atria depolarize
QRS complex: ventricles depolarize T wave: ventricles repolarize P–R interval: from start of atrial depolarization to start of QRS complex Q–T interval: from ventricular depolarization to ventricular repolarization |
|
|
What are three steps of cardiac action potential?
|
Rapid depolarization: voltage-regulated sodium channels (fast channels) open
As sodium channels close: voltage-regulated calcium channels (slow channels) open balance Na+ ions pumped out hold membrane at 0 mV plateau Repolarization: plateau continues slow calcium channels close slow potassium channels open rapid repolarization restores resting potential |
|
|
What is the absolute refractory period?
|
long
cardiac muscle cells cannot respond |
|
|
What is the relative refractory period?
|
short
response depends on degree of stimulus |
|
|
How is calcium involved in muscle contraction?
|
Contraction of a cardiac muscle cell is produced by an increase in calcium ion concentration around myofibrils
|
|
|
What is a cardiac cycle?
|
systole and diastole
|
|
|
What is a heart murmor?
|
Sounds produced by regurgitation through valves
|
|
|
What are some cardiodynamics?
|
End-diastolic volume (EDV)
End-systolic volume (ESV) Stroke volume (SV) SV = EDV — ESV Ejection fraction: the percentage of EDV represented by SV Cardiac output (CO): the volume pumped by each ventricle in 1 minute |
|
|
What are three factors that effect ESV?
|
Preload: ventricular stretching during diastole
Contractility: force produced during contraction, at a given preload Afterload: tension the ventricle produces to open the semilunar valve and eject blood |
|
|
What is cardiac reserve?
|
Difference between resting and maximal cardiac output
|
