CRAT Review
ECG graph paper
Boxes are 5mm by 5mm and indicate .04 seconds in time horizontally and .1 mV in voltage vertically
Steps to do an ECG
Clearly explain procedure, answer all questions, confident friendly manner, Patient will be cooperative if they trust you.
Bundle branches
Conducts electrical impulses down both sides of the interventricular septum
Aortic Valve or Aortic semilunar
A Semilunar valve that is located between left ventricle and aorta. Pushes blood to body. REMEMBER LEFT VENRICLE->AORTA This is a Blood flow control valve
Semilunar valve
A valve with a half moon shaped cusp that opens and close to allow blood to travel only one way. Aortic and pulmonary valves are semilunar. Separate ventricles from arteries leading to lungs and body. Send blood to body and lungs.
Mitral Valve (also known as Bicuspid valve)
Atrioventricular valve that separates the left atrium and left ventricle. Prevents back flow of blood to left atrium
Tricuspid Valve
Atrioventricular valve that separates the right atrium and right ventricle. Prevents backflow of blood to the right atrium.
PR Segment
Delay at AV node
Procedure for applying ambulatory monitor (holter)
Educate patient, equipment gathered and prepared, electrodes placed on chest, equipment hooked up
Troubleshooting consent when patient cannot read and/or write
Explain procedure to family member and have them and patient sign or explain the procedure with a witness present and have witness sign and have patient place an X on form
Heart valves
Function as the heart muscle contracts and relaxes, opening and shutting valves at alternate times passing blood on a one way trip. Each valve is 3 flaps except mitral valve which is two
AV node
Gatekeeper who's job is to slow down electrical activity, delays the electrical impulse to allow the atria to complete contraction
For HIPPA questions keep in mind:
HIPPA was enacted to protect the patient, you need two forms of identification to be sure you have right patient, you need an order to do test, connect supervisor or follow organization's procedure are usually correct ansers.
HIPPA
Health Insurance Portability and Accountability Act established in response to information being transmitted electronically Established 1996 past into law 2003. Patient info can only be shared for patients care. This includes patient address and phone number. Fines if violate law.
Cardiac Anatomy
Heart is in center of chest under sternum and in between lungs. 2/3 is left of sternum. Heart is divided into 4 chambers, 2 atria, 2 ventricles. Think of heart as a double pump.
Myocardial
Heart muscle Myo=muscle cardi=heart
Ambulatory Monitor
Most common type is holter monitor (continuous or intermittent-only records when patient has symptoms. Used for dysrhythmias, evaluation cardic meds, and checking pacemakers-24-48 hrs-up to 30 days
Septum
Muscular wall that divides right and left side of heart
Papillary Muscles
Pull down Valve and open it up (Mitral Valve) located in ventricles.
3 common ways to measure heart rate
R-R (300) method (semi accurate), 6 second method (generic), and the 1500 method (most accurate)
Correct order for analyzing ECG strip is
Rhythm (is it regular?) Rate, P-waves, PRI, then QRS. Now you can give Interpretation
Right Ventricle
Right lower chamber of heart which pumps deoxygenated blood to the lungs
Right Atrium
Right upper chamber of heart which receives blood from body
3 places you have automaticity
SA node, Junctional Tissue, ventricular
Pulmonary Valve or pulmonary Semilunar
Semilunar valve located between right ventricle and pulmonary artery. pushes blood through pulmonary truck to lungs. REMEMBER RIGHT VENTRICLE -> PULMONARY ARTERY. This is a Blood flow control valve
3 most common causes of artifact are:
Somatic tremor, wandering baseline, and AC interference
Heart receives blood from body via which 2 veins?
Superior Vena Cava and Inferior Vena Cava, both into right atrium
Key point to differentiating between supraventricular and ventricular:
Supraventricular complexes and rhythms have a normal QRS duration (.06-.10 secs) Ventricular complexes and rhythms have a wide QRS duration .12 sec or greater
Valves prevent what?
The back flow of blood
Precordial leads
The chest leads, located in front of heart (pre-in front, cordial-heart) Each chest lead begins with letter V (V1, V2, V3,V4, V5, V6) And record activity between 6 points in the heart. unipolar leads because they measure in one direction only
Digital Monitoring
Transmitted over a computer where report is verified by a licensed practitioner
Transtelephonic Monitoring
Transmitted over phone to a LICENSED practitioner to read (magnetic tape), Patients use up to 30 days
Major blood vessels of heart are:
Venae cavae, pulmonary artery, pulmonary veins, and aorta
Interventricular septum
Wall (septum) that divides the right and left ventricles
Augmented leads (called this because ECG machine increases tracing size so it is readable)
aVR, aVl, and aVF, record midway between points of Einthoven triangle. Unipolar leads because they measure between one electrode on body in one direction
Conductivity
ability of heart muscle cells to receive and transmit electrical impulses
Contractility
ability of heart muscles to shorten or contract, the contraction produces the heartbeat or pumping of heart
Chordae Tendinae
are cord-like tendons that connect the papillary muscles to the tricuspid valve and the mitral valve in the heart.
Procedure for removing
before removing, diary must be complete by patient, then turn off recording, remove electrodes, clean skin, report results *process is based on type of equipment uses
Gain
control on ECG machine that increases or decreases size of ECG tracing. Normal setting is 10mm/mV. 20mm/V will double size and 5mm/V will reduce size by half * NEED TO KNOW mV is a millivolt-unit of measurement to indicate voltage- Voltage is measures on a vertical axis
Measuring heart rate with big box formula (300 method)
count large boxes and divide the total into 300
measuring heart rate quick method (6 second method)
count number of QRS in six second strip and times by ten
measuring pauses
count number of small boxes between 2 QRS and times by .04
isoelectric line
period of no electrical activity, also known as the baseline
Speed control
regulates how fast or slow the paper or data run during procedure. MOST COMMONLY USED: 25 mm/sec *increasing the speed for example to 50mm/sec will make wave forms appear wider and is useful if patient heart rate is very fast. if you change the speed you must note on tracing by circling the setting on tracing and notify the healthcare provider *speed in measure on a horizontial axis
U-wave
represents VENTRICULAR REPOLARIZATION having a U wave could mean low potassium
P-wave
represents atrial depolarization with the resulting atrial contraction. SA node. ATRIAL DEPOLARIZATION Normal=less than .10 Anything to do with p-waves is atrium
PR interval
represents time from when electrical impulse is initiated until the ventricles are simulated (another words, how long it was held in AV node) Normal=.12-.20, measure by counting small boxes from beginning of p wave to beginning of QRS and multiple this number by .04
QRS
represents ventricular depolarization with the resulting ventricular contraction, the time it takes the electrical impulse to travel through AV node down the bundle branches to the purkinje fibers. this is the heart beat you feel or hear. VENTRICULAR DEPOLARIZATION Normal=.04-.10
T-wave
represents ventricular repolarization, ventricles relax and semilunar valve close. (Aortic and pulmonary valves)
ECG machines must be calibrated
so that 1cm=1mV
Ethics
standards of behavior/right vs wrong
Electrical part of heart....
tells the mechanical part when to work.
The EGC waveform
the recorded electrical activity produced during depolarization and repolarization
Depolarization
the state of cellular stimulation that proceeds contraction, the electrical charge is reversed and the inside becomes positive. most important electrical event in the heart as it cause the heart to contract and pump the blood. REMEMBER D. DEPOLARIZATION=ELECTRICAL DISCHARGE
EGC PAPER provides measurement for both______
time and voltage. smallest box =.04 second in time and 1mm or .1mV in voltage 2 large boxes =10mm, which equals 1cm for vertical measurement.
Coronary circulation
transportation of blood to and from heart
Pulmonary circulation
transportation of blood to and from lungs
Artifact Filter
unwanted marks on ECG tracing caused by something other than heart activity *Normal settings is between 40-150Hz, 40 Hz can be used to reduce artifact
How many seconds are between 3 tick marks on top of ecg paper?
6 seconds
ECG machine controls
# most common are speed, gain, artifact filter. also have these controls: LCD display, heart rate limits, standardization, and lead section
one small box=
.04 seconds or 40 milliseconds
one large box=
.20 seconds or 200 milliseconds
Calculating heart rate with measurement of the R-R Interval
1 box between=300bpm & .2 seconds between beats 2 box between=150bpm & .4 seconds between beats 3 box between=100bpm & .6 seconds between beats 4 box between=75bpm & .8 seconds between beats 5 box between=60bpm & 1.0 seconds between beats 6 box between=50bpm & 1.2 seconds between beats
Center for disease control & Prevention has 2 levels of precautions which are_________
1. Standard-Hand Hygiene/gloves for blood/body fluids, non-intact skin, and mucous membranes. For standard wash hands and use gloves 2.Isolation precautions-airborne, droplet, contact For Isolation wash hands, use gloves, and use personal protective equipment
five large boxes=
1.0 second or 1000 miliseconds
measuring heart rate with small boxes formula (1500 method)
1500 divided by number of small boxes between one QRS or p-wave to the next
History of ECG
1903-Wilhelm Einthoven
Functions of common ECG machine
3 basic functions are input, signal processing, output display. Sensors in ECG machine serve as receiving devices for the electrical activity of the heart. INPUT-Electrode placed on patients skin direct impulses to ECG instrument, providing the input. Signal processing happens in ECG machine, output display is the result of processing and is shown on screen (known as oscilloscope) and/or on ECG tracings. Electronic output is quickly becoming most common choice for ECG tracings.
15 large boxes=
3 seconds, there are marks every three seconds on bottom of pink ECG paper
Age to have a routine ECG
40
Automaticity
Ability of heart to initiate an electrical pulse w/o being stimulated by an outside source. Heart tissue has its own innate ability to initiate an electrical impulse
Excitability
Ability to respond to impulses, w/o which the heart could not react to the electrical impulses
Left heart
After blood picks up oxygen in lungs it is passed into left heart and pumped to body via aorta
Atria contracts when?
After the Mitral valve and Tricuspid valve opens causing ventricles to fill with blood.
Step by step to valve function in left ventricle
After the left ventricle contracts, aortic valve closes and the mitral valve opens, allowing blood flow from left atrium to the left ventricle, as the left atruim contracts, more blood flows into left ventricle. When the left ventricle contracts again, the mitral valve closes and the aortic valve opens, so blood flows into the aorta
SA node
Area of specialized cells in upper right atrium. Considered the normal pacemaker of the heart. Initiates the heart beat
What word represents a "slightly irregular" rhythm (usually caused by respiration?
Arrhythmia
Telemedicine monitoring is usually used to evaluate_____________
Artificial Pacemaker Functioning
How to heart valves function?
As the heart muscle contracts and relaxes, the valves open and shut letting blood flow into the ventricles and atria at alternate times.
Conduction system of the heart
Heartbeat originates in the sinoatrial (SA)node and travels thru the intermodal pathways to the atrioventricular (AV) node. The impulse then passing in to the AV bundle/the Bundle of HIS to the interventricular septum where it is divided between the right and left bundle branches where it travels to the apex of the heart ending in the Purkinje fibers in the right and left ventricles causing them to contract.
Tissue around AV Node is known as?
Junctional
Aorta
Large artery of the body who's job it is to transport oxygenated blood from left ventricle to the rest of body.
Pulmonary artery
Large artery that transports blood from right ventricle to the lungs. ONLY artery in body that carries deoxygenated blood.
Vena Cava
Largest veins in the body that carries deoxygenated blood on its return to the heart. Superior is upper body/arms/ head and inferior is lower body/legs
Left Atrium
Left upper chamber of heart which receives blood from the lungs
Left Ventricle
Lower left chamber that pumps oxygenated blood to the body. Biggest and strongest chamber of the heart. Work horse of the heart
Bipolar leads
Measure flow of electrical current in two directions at same time. Are the Standard limb leads, I (records tracing from right arm to left arm), II (records from right arm to left leg), and III (records tracing from left arm to left leg). Forms a triangle known as Einthoven triangle
Laws
established by government Illegal acts are always unethical but unethical acts are not always illegal Chapter 1
S-wave
first negative deflection after R wave, represents electrical conduction thru both ventricles
R-wave
first positive wave, represents conduction of electrical activity to left ventricle. Area of heart=bundle branches bicuspid and tricuspid valve closes. ventricular excitement complete, Purkinje fibers
Repolarization
follows contraction when the heart returns to neutral and the heart relaxes allow the chambers to refill REMEMBER R. REPOLARIZATION=REST & RECOVERY
Polarization
heart cells are at their peak resting energy. The inside of the cell is negatively charged and the outside is positively charged. the "ready rest stage of the heart".
Atrial repolarization
hidden in QRS do not se on ECG
Q-wave
if there it is the first negative deflection before R wave. Normal q wave is 1/4 height of R-wave. Pathologic Q waves (deeper) are a sign of previous myocardial infarction
Right heart
job is to pump deoxygenated blood to lungs where it exchanges carbon dioxide for oxygen
J point
junction of QRS and ST interval
Blood going into right heart
just delivered oxygen and nutrients to the body
Ischemia
lack of blood supply to an area of tissue due to blockage in circulation to the area
ST segment
measured from end of s wave to beginning of T wave. Normal is on the isoelectric line. if elevated or depressed it could reflect ischemia