lab 3 Heart Flashcards
P-Q interval:
the time between the beginning of atrial depolarization and ventricular depolarization
- Coronary sinus
collects deoxygenated blood from the myocardium and delivers it to the right atrium
2nd ♥ sound S2 (dup)
associated with closure of semilunar valves at the end of ventricular systole
a rapid uncoordinated heart contraction which fails to pump blood out of the heart
Fibrillation
The ability of the heart to beat is
intrinsic
internal, does not require nervous system input
Blood Pressure
normalBP
- measured in arteries
- pressure blood exerts against blood vessel walls, measured in the arteries
- Normal blood pressure range= 120/80 (systolic pressure/ diastolic pressure)
The entire heart is covered by a
serous membrane called the pericardium which has two layers: the visceral (epicardium) pericardium and the parietal pericardium.
1st ♥ sound S1 (lub) associated with
closure of AV valves at the beginning of the ventricular systole
1.Sinoatrial Node (SA node)
- located in the right atrial wall just inferior to the superior vena cava
- Sets the pace for the heart as a whole
- Known as the hearts pacemaker
- SA rhythm known as sinus rhythm determines heart rate
- Right and left bundle branches-
- located in the interventricular septum
- the AV bundle splits the impulse into 2 pathways, the right and left bundle branches
Hypertension
high blood pressure. When blood pressure exceed 140/90 mmHg.
myocardium.
The muscle of the heart is know as
The average heart beats approximately
75 times per minute
a shallow depression in the interatrial septum where an opening existed in the fetal heart (foramen ovale)
- Fossa ovalis
Murmurs
abnormal heart sounds (indicates problems with valves)
S-T interval:
Represents the time of ventricular contraction
Three Layers of the Heart Wall
Epicardium- outer protective layer (continuous with the visceral layer of the serous pericardium.
Myocardium- muscular middle layer (cardiac muscle)
Endocardium- inner layer that is continuous with the inner lining of the blood vessels
P wave
Atrial depolarization
ELECTROCARDIOGRAPHY (EKG / ECG)
—graphic recording of the electrical changes (depolarization followed by repolarization) occurring during the cardiac cycle is called an electrocardiogram
a resting heart rate above 100 beats/min; occasionally promotes fibrillation
Tachycardia
- Atrioventricular bundle (Bundle of His)-
- located in the upper atrialventricular septum
- runs from the AV node,
- the impulse sweeps to the atrioventricular bundle
- is the only electrical connection between the atria and the ventricles