Heart 112 Final Wilson Flashcards
cardiology
Study of the heart
Mediastinum
The medial cavity of the thorax
pericardium (visceral and parietal),
Double walled sac enclosing the heart (parietal layer is the outer layer and the visceral layer is the inner layer of the pericardium)
anastomosis,
union or joining of nerves, blood vessels or lymphatics
pulmonary circuit,
system of blood vessels that serves gas exchange in the lungs (i.e. pulmonary arteries, capillaries, and veins)
systemic circuit,
system of blood vessels that serves gas exchange in the body tissues
coronary sulcus,
(atrioventricular groove) encircles the junction of the atria and ventricles like a crown
intercalated disc,
specialized connections between myocardial cells containing gap junctions and desmosones
gap junction,
a passageway between two adjacent cells; formed by transmembrane proteins called connexons
plateau phase of cardiac action potential,
transmission of the depolarization wave down the T tubules causes sarcoplasmic reticulum to release Ca2+ into the sarcoplasm
electrocardiography (ECG),
used to measure electrical currents generated by the heart. Helps to determine if conduction pathway is abnormal, heart is enlarged and if certain regions are damaged.
autorhythmic (intrinsic),
self rhythmic: depolarize spontaneously and thus pace the heart.
pacemaker,
(Sinoatrial node) initiate the action potentials that spread throughout the heart to trigger its rhythmic contractions
conduction system of heart
The pacemakers and gap junctions are the route for the heart muscle depolarization wave; it does not move randomly, rather it travels in an coordinated pattern with organized timing to ensure that heart works as an effective pump.
auscultation,
listening for sounds within the body
diastole,
relaxation period of heart
systole,
contraction period of heart
cardiac output,
amount of blood pumped out by each ventricle in 1 minute
cardiac cycle,
includes all events associated with the blood flow through the heart during on complete contraction
stroke volume,
the volume of blood pumped out by one ventricle with each beat
end diastolic volume,
the amount of blood that collects in the a ventricle during diastole
end systolic volume,
the volume of blood remaining in a ventricle after it has contracted
preload,
degree to which cardiac muscle cells are stretched just before they contract
contractility,
the contractile strength achieved at a given muscle length
afterload
the pressure that the ventricles must overcome to eject blood
myocardial infarction,
heart attack; death of area of heart muscle from lack of O2
angina pectoris,
Heart pain from ischemia of cardiac muscle
arrhythmia,
irregular heart rhythm
junctional rhythm,
The SA node is nonfunctional, P waves are absent, and heart is paced by the AV node at 40-60 beats/min
fibrillation,
condition of rapid and irregular or out of phase contractions in which control of heart rhythm is taken away from the SA node by rapid activity in other heart regions.
heart block,
damage to AV node interferes with the ability of the ventricles to receive pacing impulses.
murmurs,
abnormal heart sounds due to blood striking an obstruction causing it to become turbulent.
congestive heart disease,
heart is an inefficient pump and blood circulation is inadequate to meet tissue needs.
coronary artery disease,
fatty buildup that clogs the coronary arteries
ventricular septal defect,
superior part of the inter-ventricular septum fails to form, allowing blood to mix between two ventricles.
coarctation of the aorta,
a part of the aorta is narrowed
tetraology of Fallot,
multiple defects • Pulmonary trunk too narrow and pulmonary valve stenosed • Hypertrophied right ventricle • Ventricular septal defect • Aorta opens from both ventricles
tachycardia,
abnormally fast heartbeat (more than 100 beats/min)
bradycardia
heart rate slower than 60 beats/min
What are the three layers of heart wall;
- Epicardium
- Myocardium
- Endocardium
where is thickest myocardium of the heart?
Where the great vessels issue from the heart and around the heart valves
Anatomy of the Right Atrium
- Receives blood from 3 sources (superior and inferior vena cava and coronary sinus)
- Interatrial septum partitions the atria
Anatomy of the Right Ventricle
- Forms most anterior surface of heart
- Papillary muscles (cone shaped) & trabaculae carneae
- Chordae tendineae
- Interventricular septum
Anatomy of the Left Atrium
- Forms most of the base of the heart
* 4 pulmonary veins
Anatomy of the Left Ventricle
- Forms apex of heart
* Chordae tendineae
What is the roles of the right atrium of the heart?
Receives blood from vena cava (superior and inferior) and coronary artery
What is the roles of the left atrium of the heart?
Receives blood from for pulmonary veins
What is the roles of the right ventricle of the heart?
Discharges blood into the pulmonary trunk
What is the roles of the left ventricle of the heart?
Discharges blood into the aorta
What are the major coronary arteries?
• Aorta • Left coronary artery o – anterior interventricular artery o – circumflex artery • Right coronary artery o – right marginal artery o – posterior interventricular artery
What are the major coronary veins of the heart?
- Coronary sinus
- Great cardiac vein
- Middle cardiac vein
- Anterior cardiac vein
- Small cardiac
- Superior vena cava
names/locations of heart valves,
- Tricuspid valve: Light Atrium (flows into right ventricle)
- Pulmonary semilunar valve: Right Ventricle (flows into pulmonary trunk)
- Bicuspid valve: Left Atrium (flows into left ventricle)
- Aortic semilunar valve: Left Ventricle (flows into ascending aorta)
role of calcium in cardiac action potential,
causes the plateau stage
pathway of the conduction system. (Where are pacemaker cells -> which normally sets the rhythm?),
- Sinoatrial node: sets the rhythm
- Atrioventricular node
- Atrioventricular bundle
- Right & left bundle branches
- Subendocardial conducting network
extrinsic regulation of heart rate (which branch of autonomic nervous speeds up rate? Slows down?),
- The sympathetic nervous system is “the accelerator”
* The parasympathetic nervous system is “the brakes”
Three main peaks and intervals of ECG and its correspondence to what is happening to the heart (Fig 18.17),
- P wave: atrial depolarization
- QRS complex: Ventricle depolarization
- T wave: ventricle repolarization
phases of the cardiac cycle(Fig 18.21),
- Ventricular filling (mid-to-late diastole): ventricular filling, atrial contraction
- Ventricular systole (atria in diastole): isovolumetric contraction phase, ventricular ejection phase
- Early diastole: isovolumetric relaxation, ventricular filling
three ways to regulate stroke volume,
- Preload
- Contractility
- Afterload
role of epinephrine in cardiac output control
increases heart rate
