Heart
Is a hollow muscular organ located in the thoracic cavity betwee the lungs just bhind the sternum.
Layers of the Heart
-Endocardium
-Myocardium
-Epicardium
Endocardium
The innermost layer of the heart. It forms the lining and folds back onto itself to form the four valves. It is in this layer that the conduction system is found.
Myocardium
The middle and contractile layer of the heart. It is made up of striated muscle fibers interspersed with intercalated disks.
Epicardium
The outermost layer of the heart. It is actually the inner (visceral) layer of the pericardium.
Pericardium
Is a sac in which the heart is contained.
Right Atrium
Receives deoxygenated blood returning to the heart from the body via the superior vena cava which carried blood from the upper body and the inferior vena cava which carries blood from the lower body.
Right Ventricle
Receives deoxygenated blood from the right atrium which it pumps to the lungs or oxygenation through the pulmonary artery (trunk) to the right and left pulmonary arteries.
Pulmonary Arteries
Are the ONLY arteries in the body that carry deoxygenated blood.
Left Atrium
Received oxygenated blood returning from the lungs via the right and left pulmonary veins.
Pulmonary Veins
Are the ONLY veins in the body that carry oxygenated blood.
Left Ventricle
Receives the oxygenated blood from the left atrium and pumps it to the body through the aorta.
Aorta
The latest artery of the body.
Septum
Separates the heart into a two-sided pump.
Upper Chambers of the Heart
Right and Left Atrium
Lower Chambers of the Heart
Right and Left Ventricles
The Heart Valves
The purpose of these is to prevent back flow of blood thereby assuring uni-directional flow thru the heart.
Atrioventricular Valves (AV)
So-called because they are located between the atria and ventricles.
The 2 Atrioventicular Valves
Tricuspid Valves and Mitral Valve
Tricuspid Valves
Located between the right atrium and the right ventricle. As the name connotes, it has three cusps.
Mitral Valve
Located between the left atrium and the left ventricle. It has two cusps and it also called the bicuspid valve.
Semilunar Valves
They have half-moon shaped cusps.
The 2 Semilunar Valves
Pulmonic Valve and Aortic Valve
Pulmonic Valve
Located between the right ventricle and the pulmonary trunk.
Aortic Valve
Located between the left ventricle and aorta.
Murmurs
Are cause by diseases of the valves or other structural abnormalities.
The heart sound are produces by the closure of the valves:
S1 and S2
S1
First sound is sue to the closure of the mitral and tricuspid valves.
S2
Second heart sound is due to the closure of the aortic and pulmonic valves.
The arteries supplying the heart are:
The right and left coronary from the aorta. The veins accompany the arteries, and terminate in the right atrium.
Autonomic Nervous System Abbreviation
ANS
Autonomic Nervous System
Is subdivided into the sympathetic and parasympathetic; also this influences the heart.
Sympathetic Nervous System
Affects both the atria and the ventricles by increasing heart rate, conduction and irritability.
Parasympathetic Nervous System
Affects the atria only by decreasing hear rate, conduction and irritability.
Automaticity
This is the ability of the cardiac pacemaker cells to spontaneously initiate their own electrical impulse without being stimulated from another source. Sites that posses this characteristic are the SA node, AV junction, and the Purkinje fibers.
Excitability
Also referred to as irritability. this characteristic is shared by all cardiac cells and it is the ability to respond to external stimulus: electrical, chemical, and mechanical.
Conductivity
This is the ability of all cardiac cells to receive an electrical stimulus and transmit the stimulus to other cardiac cells.
Contractility
This is the ability of the cardiac cells to shorten and cause cardiac muscle contraction in response to an electrical stimulus. This characteristic can be enhanced through administration of certain medications, such as digitalis, dopamine and epinephrine.
SA Node
Found in the upper posterior portion of the right atrial wall just below the opening of the superior vena cava. It is the primary pacemaker of the heart and has a normal firing rate of 60-100 beats per minute.
Internodal Pathways
Consists of anterior, middle and posterior divisions that distribute electrical impulse generated by the SA node throughout the right and left atria to the atrioventricular (AV) node.
AV Node
Located at the posterior septal wall of the right atrium just above the tricuspid valve. There is a 1/10th of a second delay of electrical activity at this level to allow blood to flow from the atria to the ventricles.
Bundle of His
Found at the superior portion of the interventricular septum, it is the pathway that leads out of the SA node. It has an ability to initiate electrical impulses with an intrinsic firing rate of 40-60 beats per minute.
Bundle Branches
Located at the interventricular septum, the bundle of His divides into the right and left bundle branches, the function of which is to conduct the electrical impulse to the Purkinje fibers.
Purkinje Fibers
Found within the venticular endocardium, it consist of a network of small conduction fibers the delivers the electrical impulses to the ventricular myocardium. This network has the ability to initiate electrical impulses and act as a pacemaker if the high
Limb Leads
Consist of 3 bipolar leads and 3 augmented leads. These leads record electrical potentials in the frontal plane.
Lead I
The left arm is positive and the right arm is negative.
Lead II
The left leg is positive and the right arm is negative.
Lead III
The left leg is positive and the left arm negative.
Left Arm Abbreviation
LA
Right Arm Abbreviation
RA
Left Leg Abbreviation
LL
Lead aVR
The right arm is positive and the other limbs are negative.
Lead aVL
The left arm is positive and the other limbs are negative.
Lead aVF
The left leg (or foot) is positive and the other limbs are negative.
V1
4th intercostal space, right sternal border.
V2
4th intercostal space, left sternal border.
V3
Equidistant between V2 and V4.
V4
5th intercostal space, left midclavicular line.
V5
5th intercostal space, anterior axillary line.
V6
5th intercostal space, midaxillary line.
How many electrodes are places during a routine EKG?
10 producing 12 Leads: I, II, III, aVR, aVF, aVL; V1-V6
The Electrocardiographic Grid
EKG paper.
The EKG Paper
Is a graph paper with horizontal and vertical lines at 1-mm intervals. A heavy line appears every 5mm.
1mm equals what on and EKG paper?
0.04 seconds
What does 5mm on EKG paper equal?
0.2 seconds
What does the vertical axis represent on EKG paper?
Amplitude measured in millivolts but expressed in millimeters.
0.1 mV equals what on EKG paper?
1mm
What is the tracing on the EKG paper marked by?
A stylus using heat.
Waveform
Refers to movement away from the isoelectric line either upward (positive) deflection or downward (negative) deflection.
Segment
Line between two waveforms.
Interval
Waveform plus a segment.
Complex
Several waveforms.
Atrial Activation
P wave.
P Wave
The deflection produced by atrial depolarization.
The Normal P Wave in standard, limb, and precordial leads does not exceed what?
0.11s in duration or 2.5mm in height.
Ventricular Activation
QRS Complex, Q Wave, R Wave, S Wave.
QRS Complexes
Represents ventricular depolarization (activation). The ventricle is depolarized from the endocardium to the myocardium, to the epicardium.
Q Wave
The initial negative deflection produced by ventricular depolarization.
R Wave
The first positive deflection produced by ventricular depolarization.
S Wave
The first negative deflection produced by the ventricular depolarization that follows the first positive deflection, R wave.
Ventricular Repolarization
T Wave, U Wave.
T Wave
The deflection produced by ventricular repolarization.
U Wave
The deflection seen following the T wave but preceding the next P wave. A prominent is due to hypokalemia (low potassium, blood level).
R-R Interval
This is the interval between two R waves.
P-R Interval
P wave plus PR segment.
Normal Interval for PR Interval
0.12-0.2 sec.
QRS Interval
Represents ventricular depolarization time.
Normal QRS Interval
It should be no more than 0.1 sec. in the limb leads and 0.11 sec. in the precordial leads.
PR Segment
Line from the end of the P wave to the onset of the QRS complex.
J (RST) Junction
Point at which QRS complex ends and ST segment begins.
ST Segment
From J point to the onset of the T wave.
Artifacts
Somatic Tremors, Wandering Baseline, 60-Cycle Interference, Broken Recording.
Somatic Tremors
Patient's tremors or shaking the wires can produce jittery patterns on the EKG tracing.
Normal Running Speed for an EKG Machine
25mm/sec.
Wandering Baseline
Sweat or lotion on the patient's skin or tension on the electrode wires can interfere with the signal going to the EKG apparatus causing the baseline of the tracing to move up and down on the EKG paper.
60-cycle Interference
Can produce deflections occurring at a rapid rate that may mimic atrial flutter. This is caused by electrical appliances or apparatus being used nearby while the tracing is taken.
Broken Recording
The stylus goes up and down trying to find the signal. This can be caused by loose electrode or cables or be frayed or broken wires.
Stress Testing
A noninvasive diagnostic procedure to determine the presence and severity of coronary artery disease.
How is a stress test performed?
Is performed through exercise (by having the patient walk on a treadmill or by pedaling on a bicycle), or pharmacologically (by administration of medication that causes increase in heart rate), while hooked up to an EKG monitor.
Where are the limb leads applied during a stress test?
Applied to the torso of the patient rather than on the extremities themselves.
Some indications for stress testing are:
-Evaluation of chest pain in patient with normal EKG.
-Evaluation of patient who has recently had a myocardial infartion.
-Diagnosis and treatment of arrhythmias.
Some indications for terminating the test are:
-Patient develops chest pain, SOB, or dizziness.
-Blood pressure abnormalities.
Exercise Stress Test
Is performed until at least 85% of the target heart rate is reached or symptoms or EKG changes develop which requires the test to be terminated.
Target heart rate during an exercise stress test is what?
220 minus patient's age.
Pharmacologic Stress Test
This test is appropriate for patients with physical limitation (amputees), or those who could not exercise to reach the target heart rate (elderly).
What kind of medications are given during a Pharmacologic Stress Test?
Adenosine, dipyridamole, or dobutamine are given intravenously through and IV line to cause the heart rate to climb to the target level or the same symptoms and EKG changes as the exercise test develop.
When does Pharmacologic Stress Test concluded?
After 85% of the target heart rate is achieved.
Arrhythmias of Sinus Origin
Where electrical flow follows the usual conduction pathway but is too fast, too slow, or irregular.
Normal Sinus Rate is what?
60-100 beats per minute.
Sinus Tachycardia Heart Rate
If heart rate goes beyond 100 beats per minute.
Sinus Bradycardia Heart Rate
If heart rate goes below 60 beats per minute.
Ectopic Rhythms
Electrical impulses originate from somewhere else other than the sinus node.
Conduction Blocks
Electrical impulses go down the usual pathway but encounter blocks and delays.
Preexcitation Syndromes
The electrical impulses bypass the normal pathway and, instead, go down and accessory shortcut.
Ischemia
Occurs when there is a decrease in the amount of blood flow to a section of the heart.
What does the patient usually experience during Ischemia?
Chest pain and discomfort...usually called angina.
Myocardial Infarction
Another term for heart attack.
Infarction refers to what?
To the actual death of the myocardial cells.
The hallmark of infarction on EKG is what?
Presence of abnormal Q waves.
When are Q waves considered abnormal?
If they are >1mm (0.04mm) wide and the height is greater than 25% of the height of the R wave in that lead.
Q waves indicates what during Myocardial Infarction?
Infarct or dead myocardial tissue. When the Q waves are combined with changes in T waves and ST segments, they indicate an acute MI.
Abbreviation for Myocardial Infarction
MI
The World Health Organization (WHO) criteria for the diagnosis of myocardial infarction are the presence of at least two of what?
-Clinical history of ischemic-type of chest discomfort
-Changes on serial EKG tracing
-Rise and fall in serum cardiac markers
Ambulatory EKG Monitoring
Enables the evaluation of the patient's heart rate, rhythm, and QRST morphology during the usual daily activities.
Holter Monitor
This is an ambulatory EKG done to rule out intermittent arrhythmias or ischemias that could be missed on a routine EKG.
How is a Holter Monitor used?
The patient is hooked-up to a holter monitor and EKG signals are recorded on a magnetic tape. After the prescribed duration, the patient returns the monitor to the facility and the tape is entered into a computer and scanned for abnormalities.
How many electrodes are placed on a Holter Monitor test?
5 electrodes are attached to the patient's trunk instead of the arms and legs to prevent muscle artifact.
How is the skin prepped for a Holtor Monitor test?
By abrading a thin layer of skin and then the electrodes are taped to the skin so it will adhere better and prevent from dislodging since the entire procedure will be on for 24 hours or longer.
What is done prior to a Holter Monitor test?
EKG tracing are taken with the patient lying, sitting, and standing in order to be able to identify these positional changes which can bring about substantial variation in QRST morpholoy upon playback of the tape.
Typical Electrode placement for holter monitoring:
-2 exploring electrodes are places over bone near V1 and V5.
-2 indifferent electrodes placed over the manubrium
-1 ground electrode places over the 9th or 10th rib at the right midaxillary line.
What is a positive Holter?
Is one that has recorded abnormalities that may explain the patient's symptoms.
What is a negative Holter?
Will have no significant arrhythmias or ST changes.
Artifacts: Incomplete Tape Erasure
This can result in EKG tracings belonging to two different patients confounding both the scanner and the interpreter.
Artifacts: Tape Drag Within the Apparatus
This will result in recording of spuriously rapid cardiac rhythms. A narrowing of all EKG complexes and intervals should give clue to this situation.
Artifacts: Battery Depletion
This may result in varying QRS amplitude.
Artifacts: Loose Connections
Intermittently loose connection in the insertion of the electrodes into the recording apparatus can result in the absence of all EKG signals which may mimic bradycardia-tachycardia syndrome. Clue to this artifact is the attenuated QRST morphology of the c
Artifacts: Movement of Electrodes
This may occur during scratching the chest near the electrode and can produce tracing that look like malignant ventricular arrhythmias. However, the underlying rhythm and rate remain undisturbed and should give clue to this artifact.
What kind of patients would be good for Event Monitoring testing?
Some patients have symptoms very infrequently that a holter monitor yields little useful data.
Event Monitoring
Is a hand held device carried in the patient's pocket or purse which is switched only when the patient is actually experiencing the symptom.
Where does the EKG record during Event Monitoring?
From the anterior chest wall on magnetic tape or computer chip which is scanned later the same way as that of the holter monitor or it can be transmitted by telephone to a receiving station for immediate attention.
Oxygen
Should be given to all with acute chest pain that may be due to cardiac ischemia, suspected hypoxemia of any cause, and cardiopulmonary arrest.
Prompt treatment of the hypoxemia may prevent what?
Cardiac arrest.
For patients breathing spontaneously...
Masks and nasal cannulas can be used to administer oxygen.
Epinephrine
Is indicated in the management of cardiac arrest. The chance of successful defibrillation is enhanced by administration of epinephrine and proper oxygenation.
Isoproterenal (Isuprel)
Produces an overall increase in heart rate and myocardial contractility, but newer agents have replaced it in most clinical settings. It is contraindicated in the routine treatment of cardiac arrest.
Dopamine
Is indicated for significant hypotension in the absence of hypovolemia.
Significant Hypotension is present when?
Systolic blood pressure is less than 90 mmHG with evidence of poor tissue perfusion, oliguria, or changes in mental status. Dopamine should be used at the lowest dose that produces adequate perfusion of vital organs.
Beta Blockers
-Propranolol
-Metoprolol
-Atenolol
-Esmolol
What do Beta Blockers do?
Reduce heart rate, blood pressure, myocardial contractility, and myocardial oxygen consumption which make them effective in the treatment of angina pectoris and hypertension.
Adverse effects of beta blockers are?
Hypotension, Cogegestive heart failure and broncho-spasm.
Lidocaine
Is the drug of choice for the suppression of ventricular ectopy, insluding ventricular tachycardia and ventricular flutter.
Excessive doses of Lidocaine can produce what?
Neurological changes, myocardial depression, and circulatory depression.
Symptoms of Meurological Toxicity
Drowsiness, Disorientation, Decreased hearing ability, Paresthesia, and Muscle Twitching, and eventual seizures.
Verapamil
Is used in the treatment of paroxysmal supra ventricular tachycardia (PSVT), effective in terminating more than 90% of episodes of PVST in adults and infants.
What should you monitor when a patient is taking Verapamil?
Blood pressure due to hypotension could occur.
Digitalis
Increases the force of cardiac contraction as well as cardiac output.
How common is Digitalis toxicity?
About 20%.
Symptoms of Digitalis Toxicity
Yellow Vision, Nausea, Vomiting, and Drowsiness.
Morphine Sulfate
Is the traditional drug of choice for the pain and anxiety associated with acute myocardial infarction.
Nitroglycerin
Is a powerful smooth muscle relaxant effective in relieving angina pectoris. It is effective for both exertional and rest agina.
What is ca common side effect of Nitroglycerin?
Headache.
Hypotension may occur with Nitroglycerin, what should the patient be instructed to do?
Sit or lie down while taking Nitroglycerin.
Informed Consent
This is consent given by the patient who is made aware of any procedure to be performed, its risks, expected outcomes, and alternatives.
Patient Confidentiality
All patients have a right to privacy and all information should remain privileged. Discuss patient information only with the patient's physician or office personnel that need certain information to do their job. Obtain a signed consent form to release med
This is the key concept of HIPAA.
Patient Confidentiality
Negligence
This is the failure to exercise the standard of care that a reasonable person would give under similar circumstances and someone suffers injury because of another's failure to live up to required duty of care.
4 Elements of Negligence (The 4 D's)
Duty: Duty of Care
Derelict: Breach of Duty of Care
Direct Cause: Legally recognizable injury occurs as a result of the breach of duty of care
Damage: Wrongful activity must have caused the injury or harm that occurred.
Tort
Is a wrongful act that results in injury to one person by another.
Battery
The basis of tort in this case is the unprivileged touching of one person by another.
When the procedure is to be performed, what should the patient give?
Constent.
Invasion of Privacy
This is the release of medical records without the patient's knowledge and permission.
Defamation of Character
This consists of injury to another person's reputation, name, or character through spoken (slander) or written (libel) words.
Good Samaritan Law
This law deals with the rendering of 1st aid by health care professionals at the scene of an accident or sudden injury.
The Good Samaritan Law encourages what?
Health care professionals to provide medical care within the scope of their training without the fear of being sued for negligence.
Infections Control/Chain of Infection
This consists of links, each of which is necessary for the infectious disease to spread.
Agents
Are infectious microorganisms that can be classified into groups namely: viruses, bacteria, fungi, and parasites.
Sinus Rhythm
Sinus Rhythm P Wave
Upright, one for every QRS complex.
Sinus Rhythm PR Interval
0.12 to 0.20 seconds.
Sinus Rhythm QRS Duration
0.04 to 0.10 seconds.
Sinus Rhythm Ventricular Rate
60 to 100.
Sinus Rhythm Regularity
Regular.
Sinus Bradycardia
Sinus Bradycardia P Wave
Upright, one for every QRS complex.
Sinus Bradycardia PR Interval
0.12 to 0.20 seconds.
Sinus Bradycardia QRS Duration
0.04 to 0.10 seconds.
Sinus Bradycardia Regularity
Regular.
Sinus Tachycardia
Sinus Tachycardia P wave
Upright, one for every QRS complex.
Sinus Tachycardia PR interval
0.12 to 0.20 seconds.
Sinus Tachycardia QRS duration
0.04 to 0.10 seconds.
Sinus Tachycardia Regularity
Regular.
Sinus Arrhythmia
Sinus Arrhythmia P wave
Upright, one for every QRS complex.
Sinus Arrhythmia PR Interval
0.12 to 0.20 seconds.
Sinus Arrhythmia QRS Duration
0.04 to 0.10 seconds.
Sinus Arrhythmia Ventricular rate
Usually 60 to 100/min, can be slower or faster.
Sinus Arrhythmia Regularity
Irregular.
Atrial Fibrillation
Atrial Fibrillation P Wave
None; fibrillatory waves.
Atrial Fibrillation PR Interval
None.
Atrial Fibrillation QRS Duration
Less than 0.12 seconds.
Atrial Fibrillation Ventricular Rate
60 to 100/min
Atrial Fibrillation Atrial Rate
300 to 600/min
Atrial Fibrillation Regularity
Irregularly Irregular.
Atrial Fibrillation with Rapid Ventricular Response Abbreviation
AF-RVR
Atrial Fibrillation with Rapid Ventricular Response P wave
None: fibrillatory wave
Atrial Fibrillation with Rapid Ventricular Response PR Interval
None.
Atrial Fibrillation with Rapid Ventricular Response QRS Duration
Less than 0.12 seconds.
Atrial Fibrillation with Rapid Ventricular Response Ventricular Rate
Greater than 100/min.
Atrial Fibrillation with Rapid Ventricular Response Atrial Rate
300 to 600/min.
Atrial Fibrillation with Rapid Ventricular Response Regularity
Irregularly Irregular.
Atrial Flutter
Atrial Flutter P wave
None; flutter waves.
Atrial Flutter PR Interval
None.
Atrial Flutter QRS Duration
Less than 0.12 seconds.
Atrial Flutter Ventricular Rate
Usually 60 to 100/min; often seen at 130, 150, 160.
Atrial Flutter Atrial Rate
240 to 320/min.
Atrial Flutter Regularity
Regular (irregular with variable conduction).
Portal of Exit
The method by which an infectious agent leaves its reservoir.
Standard Precautions and Transmission-Based Precautions
Are control measures aim at preventing the spread of the disease as infectious agents exit the reservoir.
Mode of Transmission
Specific ways in which microorganism travel from the reservoir to the susceptible host.
5 Main Types of Mode of Transmission:
-Contact: direct and indirect
-Droplet
-Airborne
-Common Vehicle
-Vectorborne
Portal of Entry
Allow the infectious agent access to the susceptible host.
Common Sites for Portal of Entry
Are broken skin, mucous membranes, and body systems exposed to the external environment such as the respiratory, gastrointestinal, and reproductive.
Susceptible Host
The infectious agent enters a person who is not resistant or immune.
Medial Asepsis
The destruction of pathogenic microorganism after they leave the body.
The most important means of preventing the spread of infection is what?
Handwashing.
Abbreviation for Personal Protective Equipment
PPE
PPE includes:
-Masks
-Goggles
-Face Shields
-Respirator
Two Tiers of Isolation Precautions
-Standard Precautions
-Transmission-Based Precautions
Standard Precautions
This is an infection control method designed to prevent direct contact with blood and other body fluids and tissues by using barrier protection and work control practices.
Under the standard Precautions, all patients are presumed to be infective for what?
Blood-borne pathogens.
Infection control practices is to be used with what/who?
All patients.
Transmission-Based Precautions
The 2nd tier of precautions and are to be used when the patient is known or suspected of being infected with contagious disease.
Contact Precautions
Are designed to reduce the risk of transmission of microorganisms be direct or indirect contact.
Direct-Contact Transmission
Involves skin-to-skin contact and physical transfer of microorganisms to a susceptible host from an infected or colonized person.
Indirect-Contact Transmission
Involves contact with a contaminated intermediate object in the patient's environment.
Airborne Precautions
Are designed to reduce the risk of airborne transmission of infectious agents.
Droplet Precautions
Are designed to reduce the risk of droplet transmission of infectious agents.
Latex Sensitivity
Is an emerging and important problem in the health care field.
Informed Consent
This is given by the patient who is made aware of any procedure to be performed, its risks, expected outcomes, and alternatives.
The key concept of HIPPA is what?
Patient confidentiality.
Negligence
This is the failure to exercise the standard of care that a reasonable person would give under similar circumstances and someone suffers injury because of another's failure to live up to a required duty of care.
The 4 Element of Negligence (4 D's)
-Duty: duty of care
-Derelict: Breach of duty of care
-Direct Cause: Legally recognizable injury occurs as a result of the breach of duty of care.
-Damage: Wrongful activity must have caused the injury r harm that occurred.
Premature Atrial Complex (PAC)
Atrial depolarization that occurs early in cardiac cycle.
Supraventricular Tachycardia P wave
May be hard to find; if present, one per QRS complex.
Supraventricular Tachycardia PR Interval
Usually not measurable.
Supraventricular Tachycardia QRS Duration
0.04 to 0.10 seconds
Supraventricular Tachycardia Ventricular Rate
150 to 240/min
Rhythm regularity
Regular
Junctional Rhythm
Junctional Rhythm P wave
Absent or inverted
Junctional Rhythm PR Interval
None, or 0.12 to 0.20 seconds.
Junctional Rhythm QRS Duration
0.04 to 0.10 seconds, may extend to 0.12 seconds.
Junctional Rhythm Ventricular Rate
40 to 60/min.
Junctional Rhythm Rhythm Regularity
Regular.
Junctional Bradycardia
Junctional Bradycardia P wave
Absent or inverted.
Junctional Bradycardia PR Interval
None, or 0.12 to 0.20 seconds.
Junctional Bradycardia QRS duration
0.04 to 0.10 seconds, may extend to 0.12 seconds.
Junctional Bradycardia Ventricular Rate
Less than 40/min.
Junctional Bradycardia Rhythm Regularity
Regular.
Accelerated Junctional Rhythm QRS Duration
0.04 to 0.10 seconds, may extend to 0.12 seconds.
Accelerated Junctional Rhythm P wave
Absent, inverted, retrograde, or inverted and retrograde.
Accelerated Junctional Rhythm PR Interval
None, or 0.12 to 0.20 seconds.
Accelerated Junctional Rhythm Regularity
Regular.
Idioventricular Rhythm P wave
None.
Idioventricular Rhythm PR interval
None.
Idioventricular Rhythm QRS Duration
Greater than 0.12 seconds.
Idioventricular Rhythm Ventricular Rate
20 to 40/min
Idioventricular Rhythm Regularity
Regular.
Polymorphic Ventricular Tachycardia
Polymorphic Ventricular Tachycardia P wave
None
Polymorphic Ventricular Tachycardia PR Interval
None
Polymorphic Ventricular Tachycardia QRS Duration
Greater than 0.12 seconds
Polymorphic Ventricular Tachycardia Ventricular Rate
Greater than 120/min.
Polymorphic Ventricular Tachycardia Regularity
Regular
Ventricular Tachycardia
Ventricular Tachycardia P wave
None
Ventricular Tachycardia PR Interval
None
Ventricular Tachycardia QRS Duration
Greater than 0.12 seconds
Ventricular Tachycardia Ventricular Rate
Greater than 120/min
Ventricular Tachycardia Rhythm Regularity
Regular.
Ventricular Fibrillation
Ventricular Fibrillation P wave
None
Ventricular Fibrillation PR Interval
None
Ventricular Fibrillation QRS Duration
None
Ventricular Fibrillation Ventricular Rate
Greater than 300/min
Ventricular Fibrillation Rhythm Regularity
Irregular.
Asystole
Premature Ventricular Complex
Premature Ventricular Complex occurs when?
Early in cardiac cycle.
First Degree Heart Block
Slow or delayed conduction through AV node.
First Degree Heart Block PR Interval
Prolonged; greater than 0.20 seconds.
First Degree Heart Block P wave
One for every QRS.
Which heart block is the most dangerous?
Third Degree
Second Degree Type 1 Heart block is also called what?
Mobitz 1; Wenckebach
Second Degree Type 1 Heart block P Wave
One for every QRS
Second Degree Type 1 Heart block PR Interval
Elongates; eventually a QRS complex is lost.
Second Degree Type 1 Heart block QRS duration
Usually 0.08 to 0.12 seconds; can be wider.
Second Degree Type 1 Heart block Ventricular Rate
Usually 60 to 100/min; can be slower.
Second Degree Type 1 Heart block Atrial Rate
Usually 60 to 100/min
How do you measure Atrial rate?
By counting P waves.
Second Degree Type 1 Heart block Regularity
Irregular
Second Degree Type II Heart block is also called?
Mobitz II
Second Degree Type II Heart block P wave
Two or more for every QRS complex.
Second Degree Type II Heart block PR interval
Constant
Second Degree Type II Heart block QRS Duration
Usually 0.08 to 0.12 seconds, can be wider.
Second Degree Type II Heart block Ventricular Rate
Usually 60 to 100/min, can be slower.
Second Degree Type II Heart block Atrial Rate
Usually 60 to 100/min.
Second Degree Type II Heart block Regularity
Usually regular.
J Point
Junction point between the QRS complex and the ST segment.
Ischemia appears on an EKG how?
ST segment depression and/or T wave inversion.
How does Injury appear on an EKG?
ST segment elevation in 2+ contiguous leads.
How does infarction appear on the EKG?
Presence of pathological Q waves does not rule out acute cardiac event.
Reciprocal Changes
Changes that occur as a result of opposing view angles between leads.
Paper Speed for and EKG
25 mm/second