EKG and Cardiovascular Testing Flashcards
(125 cards)
What does the electrocardiograph do?
Record the heart’s electrical activity
What is the electrocardiogram?
A representation of the results.
How can the medical assistant alleviate a patient’s anxiety when undergoing cardiac testing?
Display sensitivity; address questions and concerns; provide excellent communication and clear instructions; if possible, prove the patient with a timeline on when to expect results; offer reassurance
What does the P wave represent?
Atrial depolarization, contraction of the atria.
What does the QRS wave represent?
Ventricular depolarization, contraction of the ventricles.
What does the T wave represent?
Ventricular repolarization, relaxation of the ventricles.
What does the U wave represent?
Repolarization of the bundle of His and Purkinje fibers.
What does the PR interval represent?
Time from the beginning of atrial depolarization to the beginning of ventricular depolarization.
Where does the PR interval begin and end?
Starts at the beginning of the P wave and ends at the beginning of the Q wave.
What does the QT interval represent?
Time from the beginning of ventricular depolarization to the end of ventricular repolarization.
Where does the QT interval begin and end?
Starts at the beginning of the Q wave and ends at the end of the T wave.
What does the ST segment represent?
Time from the end of ventricular depolarization to the beginning of ventricular repolarization.
Where does the ST segment begin and end?
Starts at the end of the S wave and ends at the beginning of the T wave.
During which wave does atrial repolarization occur?
QRS wave. (It is not visible but occurs during this phase.)
What is a sinus rhythm characterized as?
The presence of 1 P wave for each QRS interval on the EKG
What is a sinus dysrhythmia?
Slight irregularity in the QRS complexes in an otherwise normal EKG
What is the defining characteristic of sinus bradycardia?
Heart rate less than 60 beats per minute
What are the defining characteristics of sinus tachycardia?
Heart rate greater than 100 beats per minute, with one P wave preceding each QRS complex.
What is sinus arrest?
A break in the normal EKG rhythm where the SA node fails to fire.
When is sinus arrest considered significant?
When the person experiences symptoms such as shortness of breath, fainting, or chest pain, or if the periods of arrest last longer than 6 seconds.
Where do atrial rhythms originate?
Atrial tissue, outside the SA node.
What is a characteristic feature of atrial rhythms on an EKG?
Absence of normal P waves.
List three commonly encountered atrial rhythms.
Atrial flutter, atrial fibrillation, and premature atrial contractions (PACs).
What is atrial flutter?
A rapid heart rhythm that originates in the atria.