EKG and Cardiovascular Testing Flashcards
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.
How is atrial flutter characterized on an EKG?
Multiple flutter waves for each QRS complex.
How is atrial flutter treated?
Medication to control the rate.
What is atrial fibrillation?
Rapid, disorganized firing of multiple sites within the atrial tissue.
How is atrial fibrillation characterized on an EKG?
Lots of fibrillatory waves between QRS complexes, irregular QRS rhythm.
What is a significant risk associated with atrial fibrillation?
Increased risk of blood clots.
What medication may be prescribed to patients with atrial fibrillation?
Blood thinners.
What are premature contractions?
Contractions that occur earlier than they should.
What are premature atrial contractions (PACs)?
Premature contractions that originate in the atria.
What are premature ventricular contractions (PVCs)?
Premature contractions that originate in the ventricles.
How many premature contractions per minute are considered abnormal?
More than 6 per minute.
What type of arrhythmias typically require immediate intervention?
Ventricular arrhythmias.
List three ventricular arrhythmias that require immediate attention.
Ventricular tachycardia, ventricular fibrillation, and asystole.
Describe the QRS complexes in ventricular tachycardia (V-tach).
Large, irregular, and wide.
What is the appearance of P waves in V-tach?
Typically absent, not visible, or occur randomly.
What causes ventricular tachycardia?
A single area in the ventricles firing outside the normal conduction pathway.
Do patients with V-tach always have a pulse?
Frequently do not, but it is possible to have a pulse.
Is ventricular tachycardia life-threatening?
Yes
How should V-tach be handled?
Reported immediately.
What are the treatments for V-tach?
Medication and/or cardioversion.
What can V-tach progress to if untreated?
Ventricular fibrillation.
What happens to the ventricles during ventricular fibrillation?
They twitch or quiver, not pumping blood.
Does ventricular fibrillation produce a pulse?
No.
What is the typical state of consciousness for a patient in ventricular fibrillation?
Unconscious within seconds.
What is asystole?
Complete absence of any waves on the EKG tracing.
What is the first step to take if asystole is observed on an EKG?
Immediately check if the patient is awake and alert.
If the patient is awake and alert and asystole is observed, what is the likely cause?
A disconnected electrode.
If the patient is not awake and asystole is observed, what steps should be taken?
Call 911 and begin CPR.
What are somatic tremors characterized by on an EKG tracing?
Irregular spikes throughout the tracing.
What is the primary cause of somatic tremors in an EKG?
Muscle movement.
What is an example of a physiological cause of somatic tremors?
Shivering due to cold.
What medical condition can cause somatic tremors?
Parkinson’s disease.
How can somatic tremors be reduced?
Decreasing patient anxiety, providing warmth and comfort.
What position can reduce somatic interference in patients with uncontrolled muscle movement?
Laying their hands palms-down under their buttocks.
What are the characteristics of AC interference on an EKG tracing?
Regular spikes.
What is the primary cause of AC interference?
Poor grounding or external electricity interfering with the tracing.
What are some examples of nearby electrical equipment that can cause AC interference?
Lights, computers, and other items plugged into wall sockets.
How can AC interference be prevented or reduced?
Ensure proper grounding using a three-prong plug, avoid crossed lead wires, move the bed away from the wall, and turn off unnecessary electronic devices.
What is a wandering baseline?
A baseline that moves away from the center of the paper, making interpretation difficult.
What is the primary cause of a wandering baseline?
Movement associated with breathing or poor electrode connection.
How can a wandering baseline be prevented?
Clean the skin before attaching the electrodes and instruct the patient to avoid using creams and lotions.
What is an interrupted baseline?
A break in the EKG tracing.
What is the most common cause of an interrupted baseline?
A disconnected or broken lead wire.
What does an interrupted baseline look like on an EKG tracing?
A flat, horizontal line.
How can interrupted baselines be prevented?
Regular cleaning, maintenance, and inspection of lead wires.
Which artifact is most likely caused by other electrical equipment in the room?
60 cycle interference
What patient preparation is necessary regarding clothing and jewelry before an EKG?
Patient undresses from the waist up, lower legs/ankles accessible. Remove pantyhose, tights, socks, and jewelry (bracelets, necklaces). Provide a drape or gown with front opening, and offer additional cover for privacy.
What steps should be taken to minimize electrical interference during an EKG?
Turn off and remove all electronic devices (cell phones) from the patient.
What is the standard patient position for an EKG, and what alternative is acceptable?
Standard position is supine (lying flat on back). Alternative: semi-Fowler’s position (45-degree angle) if patient cannot lie flat.
What skin preparation is important before placing EKG electrodes?
Instruct patient to avoid lotions, powders, oils, ointments. Clean skin with alcohol wipes, soap and water, or electrolyte pads at electrode sites.
What should be done if chest hair interferes with electrode placement?
Clip the hair using surgical clippers (preferred). Use regular razors only if clippers are unavailable, being mindful of potential skin abrasions.
How many electrodes are placed on the body for a standard 12-lead EKG, and why?
10 electrodes, to record heart activity from 12 different angles and planes.
What is the purpose of the electrolyte gel used with EKG electrodes?
It serves as a conductor of the electrical impulses from the heart.
What can poor-quality or expired electrodes or gel cause during an EKG?
Artifacts on the tracing, which can interfere with producing a clean and accurate reading.
What do the horizontal and vertical axes on EKG graph paper represent, and what are their standard measurements?
The vertical axis represents gain or amplitude (10 mm or 1 mv). The horizontal axis represents time (each small square is 0.04 seconds; large squares (that has 5 small squares in it) are 0.20 seconds).
What is the normal speed at which EKG paper should run?
25 mm/second.
Where is the V1 lead placed?
4th, R Sternum
Where is the V2 lead placed?
4th, L Sternum, Directly across from V1
Where is the V4 lead placed?
5th, L Chest, midclavicular line
Where is the V3 lead placed?
L Chest, Midway between V2 and V4
Why is V4 placed before V3?
Because V3 is placed midway between V2 and V4, making it dependent on the placement of V4.
Where is the V5 lead placed?
5th, L Chest, Anterior axillary line
Where is the V6 lead placed?
5th, L Chest, Midaxillary line
What should you avoid when connecting the precordial lead wires?
Excessive tension or crossing of the wires, which could lead to artifacts.
Why should the MA be familiar with the universal lead wire colors?
In case markings are not clearly visible.
What color is the lead wire for the right arm?
White (Right)
What color is the lead wire for the left arm?
Black
What color is the lead wire for the left leg?
Red
What color is the lead wire for the right leg?
Green
Where should limb electrodes be placed?
On fleshy areas of the skin and within the same general vicinity on each limb.
What should be done if a patient has an amputated limb when placing limb electrodes?
Place the electrode on the remaining upper portion of the limb (e.g., upper thigh for a lower leg amputation).
Which leads originate from the arm and leg electrodes?
The first six recorded leads.
What type of leads are Leads I, II, and III?
Bipolar leads.
What do bipolar leads record?
Impulses that travel from a negative to a positive pole at specific positions in the heart.
What does Lead I record?
Impulses between the right and left arms.
What does Lead II record?
Impulses between the right arm and left leg.
What does Lead III record?
Impulses between the left arm and left leg.
What height should the standardization mark be on an EKG printout?
10 mm high.
What should the direction of the R wave be in Lead I, and what does a negative deflection indicate?
The R wave should have a positive deflection. A negative deflection indicates the limb leads are not attached correctly.
What are some key points to remember when preparing a patient for an EKG to minimize artifacts and ensure accurate results?
Explain the procedure to reassure the patient, uncover the chest, upper arms, and lower legs, instruct the patient to breathe normally to avoid a wandering baseline, and ensure proper positioning of the electrocardiograph machine to reduce 60-cycle interference.
What are the medical assistant’s responsibilities regarding the electrodes and lead wires after an EKG?
Connect electrodes and lead wires correctly, position chest electrodes downward to prevent pulling and artifacts, and reseal the electrode pouch to preserve moisture.
What should the medical assistant monitor during the EKG recording to ensure a proper tracing?
A universal standardization mark, a baseline tracking through the middle of the tracing, no abnormal spikes in the baseline, and visible P, QRS, and T waves, with waveforms being positively deflected (unless there is cardiac pathology).
What should the MA instruct the patient to do while recording the EKG?
Lie still
What should the MA check for after the EKG has been recorded to ensure validity?
Standardization mark that is 10mm high
What should the MA do first if a patient develops shortness of breath while they are recording the EKG?
Notify the provider
What should the MA do after recording an EKG?
Give it to the provider for interpretation
What two main settings can be adjusted on an EKG machine, and what do they represent?
Gain (amplitude or height of the EKG waves) and paper speed (speed at which the EKG paper comes out of the machine).
What are the standard dimensions of the calibration box on an EKG tracing, and what does it help the MA determine?
10 mm tall by 5 mm wide; it helps the MA determine the calibration setting.
What is the greatest risk associated with stress testing, and where is it typically performed?
Cardiac arrest; typically performed in hospital environments with thorough monitoring and emergency equipment.
What are the medical assistant’s responsibilities during a stress test?
Assisting the provider by attaching leads, monitoring vital signs, and providing patient education including pre- and post-procedure instructions.
What are the medical assistant’s responsibilities regarding ambulatory cardiac monitoring (Holter monitoring)?
Attaching electrodes to the patient’s chest and providing patient education for accurate results.
What instructions should the medical assistant provide to a patient wearing a Holter monitor?
Maintain normal activities and keep a detailed diary, press the “event” button for cardiac or neurological symptoms and record the event, avoid moving the electrodes, avoid showers, and avoid exposure to electrical forces like metal detectors.
What patient instructions should the MA tell prior to performing the EKG?
-Turn off all electronic devices, such as cell phones, and remove them from his pockets
-Any jewelry should be removed
-Lie still and not to talk or move during the EKG reading
Which artifacts is a result of a patient movement with breathing?
Wandering baseline
The MA notices frequent, regular spikes on the EKG tracing, what should the MA do?
Frequent regular spikes are seen with 60-cycle interference caused by nearby electrical equipment
What differentiates sinus tachycardia from ventricular tachycardia?
Sinus tachycardia has narrow QRS complexes. Ventricular tachycardia has wide QRS complexes
How do somatic tremors differentiate from 60-cycle interference?
Somatic tremors are caused by involuntary muscle movement and produce irregular spikes and artifacts. 60-cycle interference is characterized by regular spikes in the EKG tracing
What can cause a wandering baseline?
A patient with lotion or cream on the skin
How many electrodes are needed to record a 12-lead EKG?
10
What should a patient who is experiencing a somatic tremor artifact on their electrocardiogram due to uncontrolled music movements?
Have patient lay their hands with the palms down under their buttocks to reduce somatic interference
What serves as a conductor of impulses during an EKG?
Electrolyte gel
What is the standard height of the calibration box?
10 mm
