Cardiac Flashcards
Where is the heart located?
Lies in the mediastinum
Extends downward and to the left
What are the 3 layers of tissues of the heart?
Endocardium
Myocardium
Epicardium
What does the atria do?
Receives blood returning from body and lungs
What do the ventricles do?
Pumps blood to the body
and lungs
What is the purpose of capillaries?
Permits gas exchange, the transfer of nutrients and the
removal of waste between blood and the fluid of tissues
The SA node is the ___________
pacemaker of the heart
__________ is the contraction phase of the heart
systole
____________ is the relaxation phase of the heart
Diastole
Atria and ventricles contract and relax in a ___________
Organized fashion
What is cardiac output?
total amount of blood ejected from one ventricle of
the heart in L/min.
What is a normal cardiac output for a healthy adult at rest?
5-6 L/min
How is cardiac output calculated?
Stroke Volume times heart rate
What is stroke volume?
The volume of blood ejected by one ventricle per
heartbeat.
what 3 factors determine stroke volume?
preload, afterload, and contractility
What causes S1 heartbeat?
the first heart sound heard indicates the closure of the mitral and tricuspid valves (Lub)
what causes the S2 heartbeat?
the second heart sound signifies the closure of the aortic and pulmonic valves (Dub)
S3 and S4 are________
Abnormal heart sounds that require further assessment
Cardiac murmurs have a whooshing sound and indicate_______
Turbulent blood flow through normal or abnormal valves
What is pericardial friction rub?
an abnormal heart sound that is typically heard
over the left sternal boarder. (Grating sound)
What does a electrocardiogram do?
Records cardiac electrical activity
P wave is ___
atrial depolarization
What does the PR interval represent?
The rate of cardiac impulse transmitted from the
AV node.
What is the QRS complex?
Ventricular depolarization
ST segment
Follows ventricular depolarization and occurs prior to
the start of ventricular repolarization.
What is the T wave?
Ventricular repolarization is occurring
What is the QT interval?
The time for ventricular repolarization to complete.
Clients may be ______ or _______ with sinus bradycardia
Symptomatic or asymptomatic
Symptoms of sinus bradycardia:
fatigue, increased shortness of breath, dizziness
Main concern with sinus bradycardia
fall risk