Mod 2 - EKG Acquisition Flashcards
what is the sac around the heart called
pericardium
what are the layers of the heart wall from inner to outermost
endocardium, myocardium, epicardium
what is the purpose of the chordae tendineae
support valve leaflets
the tricuspid valve is between the
right atrium and right ventricle
the bicuspid valve separates the
left atrium and left ventricle
aka bicuspid valve
mitral valve
the pulmonary valve is between the
right ventricle and pulmonary arteries
the aortic valve is in between the
left ventricle and aorta
aortic and pulmonary valves are both ___ valves
semilunar
the coronary arteries perfuse during ____ compared to the rest of the circulatory system which perfuses during _____
ventricular diastole; ventricular systole
the right and left coronary arteries stem from the
root of the aorta
the right coronary artery carries blood to
right atrium, right ventricle, part of left atrium, inferior wall of left ventricle, SA & AV node
the left main coronary artery splits into the
left circumflex artery and left anterior descending artery
the left main coronary artery carries oxygenated blood to the
myocardium
the left circumflex artery supplies blood to
posterolateral aspect of left ventricle
the left anterior descending artery supplies blood to the
anterior wall of the left ventricle
LAD is called the widow maker bc occlusion can lead to
ventricular arrhythmias and death
occlusion of the right coronary artery can cause
extreme sinus bradycardia
the P wave is a result of
atrial depolarization
what is the AV junction
AV node and bundle of His
what can function as a backup pacemaker if the SA node fails
AV junction
the AV junction fires at
40-60 bpm
what is the purpose of AV node
hold electrical signal from SA node to allow ventricles to fill
what does the PR interval signify
time needed for impulse to travel from SA to AV node
what is the expected PR interval
0.12-0.2 seconds
what can cause the PR interval to increase
AV node not conducting impulses
how do complete heart blocks happen
AV node can’t conduct impulse from SA to ventricles
the AV node is perfused by the
av artery
occlusion of the AV node artery causes
high-degree heart block on EKG
the large coronary arteries are not interconnected, but ppl with this disease may cause collateral circulation through the formation of small arteries
coronary heart disease
define AUTOMATICITY
ability of cardiac cells to spontaneously generate electrical activity not from a node
define ECTOPIC BEATS
beats caused by area of heart other than SA node
how can ectopic beats manifest on an EKG
premature atrial, junctional, or ventricular complexes
what are the 3 internodal pathways that connect the SA and AV node
anterior, medial, and posterior
what is the internodal pathways connecting the right and left atrium
Bachmann’s bundle
aka Bachmann’s bundle
interatrial tract
aka bundle of His
atrioventricular bundle
the left bundle branch splits into the
left anterior fascicle and left posterior fascicle
the left anterior fascicle runs along the
anterior surface of the heart
the left posterior fascicle receives additional blood from the RCA in addition to the LAD causing it to be
more resistant to ischemia
in the absence of the SA and AV node, the purkinje fibers at a rate of
20-40/min
each small box on the y-axis represents
0.1 mV
each small box on the x-axis represent
0.04 seconds
1 large box on the x axis represents
0.2 seconds
1 large box on the y-axis represents
0.5 mV
the standard paper speed is
25 mm/seconds
aka standard amplitude
gain
what is the standard amplitude
10 mm/1mV
what is the standard calibration box size
10 mm tall by 5 mm wide
define PRECORDIAL LIEADS
6 EKGs placed on anterior chest to record unipolar electrical activity of the heart at a specific location
define AUGMENTED LEADS
unipolar leads created by combining 2 of 3 limb leads to create a positive electrode
define WILSON’S CENTRAL TERMINAL
reference point created by 3 limb leads and is center of Einthoven’s triangle
what is the reference point of all unipolar leads
wilson’s central terminal
unipolar leads are all
positive
which leads are bipolar
standard limb (1,2,3)
what does a thick band of color usually pink or red on the border of the EKG graph paper indicate
the paper is running low
the paper speed can be set to ____ to slow the appearance of an EKG in a person experiencing tachycardia
50 mm/sec
some ekgs can be set to ___ to interpret a pt with bradycardia
12.5 mm/sec
when should you increase the amplitude to 20 mm/mV
tracing produces very small waveforms
when is a decrease in amplitude to 5 mm/mV warranted
waveforms too large and exceed height of paper
which demographic often requires a decreased amplitude
children
the calibration marker will change in ___ when the speed is altered
width
the calibration marker will change in _____ based on the amplitude
height
how can pt’s arms be positioned if they are nervous/have Parkinson’s
palms downward under the glutes or crossed on the abdomen
how can late stage pregnant pts be positioned
slightly on left side with pillow supporting back
what should a pt do if they experience itching, swelling, or redness at the site of electrode placement during a telemetry monitoring
call provider’s office
if you cannot place electrodes on the arms of a pt, where should they be placed
close as possible to point of shoulder attachment
what are the 12 leads on a 12 lead EKG
- Leads I, II, III
- avF, avR, avL
- V1-6
what does avR stand for
augmented vector right
what does aVL stand for
left wrist
what does aVf stand for
augmented vector foot
lead I records impulses inbetween
left and right arm
lead II records impulses between
right arm and left leg
lead III records impulses between
left arm and left leg
what is the leg used for leads I, II, III and AV leads
left
the AVL involves the
left leg and right arm
the AVR involves the
left arm and left leg
the AVF involves the
right and left arms
define ANGLE OF LOUIS
sternal angle
the color of the right arm lead is
white
the color of the left arm lead is
black
the color of the left leg lead is
red
the color of the right leg lead is
green
V1 is typically
red
V2 is typically
yellow
V3 is typically
green
V4 is typically
blue
V5 is typically
orange
V6 is typically
purple
holter monitors are commonly
5 leads
for a 12 lead, should electrodes be placed over bone
no
should electrodes for 5 lead ekgs be put on bone
yes
for a 5 lead, the white lead can be placed
right sternal border first rib OR right chest about 2 inches below clavicle
in a 5 lead, the red lead can be placed
right sternal border third rib OR left chest lower rib cage
in a 5 lead, the black lead can be placed
left side anterior axillar line fifth rib OR left chest opposite white lead
in a 5 lead, the brown lead can be placed
left sternal border first rib directly opposite white lead OR right chest fourth rib
in a 5 lead, the green lead is placed
right lower thoracic area anywhere on rib cage OR right lower chest over a rib
in a 3 lead, the white lead is placed
right shoulder just below clavicle
in a 3 lead, the black lead is placed
left shoulder just below clavicle
in a 3 lead, the red lead is placed
below left pectoral muscle at apex of the heart
which pts may need a right sided 12 lead ekg
- pts younger than 8
- pts with inferior wall ST segment elevation, myocardial infarction, dextrocardia,
what instance may require a posterior ekg
inferior wall infarction
where do V7, V8, and V9 go
underneath left scapula
define POSITIVE DEFLECTION
portion of waveforms above isoelectric line
positive deflection indicate that the leads are
appropriately attached
define NEGATIVE DEFLECTION
downward presentation of waveforms below isoelectric line
negative deflections indicate
improper attachment of leads
positive and negative deflection appears in
lead I
how does limb lead reversal appear as on the ekg
- lead I inverted
- leads II and III switch places
- AVR and AVL switch places
the baseline represents
repolarization
define REPOLARIZATION
relaxation
movement of the cables/leads, pt movement, loose or dry electrodes, pt’s labored breathing, and improper skin preparation are causes of this artifact
wandering baseline
what are ways to eliminate wandering baseline
- clean attachment sites prior
- educate pt on how to breathe and when to not talk
- reposition limb leads on fleshy areas
aka AC interference
60 cycle interference
how does AC interference manifest
uniform sharp spikes throughout tracing
what are potential causes of AC interference
- table moved away from wall
- ekg plug is tight and snug into outlet
- cell phone
- metal
- medical devices like insulin pumps
how does an interrupted baseline manifest
break in baseline or fully nonrecorded lead
cause of interrupted baseline
broken lead wires or disconnected leads
how do you calculate target heart rate for a stress test
(220-age) x 0.85
how does a stress test work
increasing speed and incline of a treadmill every 3 min until reach target heart rate
how often is BP measured during a stress test
incremental readings within first 3 min and before every transition
how long should pts be monitored after a stress test
every 3-5 min for 10-15 min
the target heart rate is generally
60-85% of maximum heart rate
what are signs of pt distress during a stress test
dizziness, lightheadedness, nausea, severe SOB, tingling sensations, numbness, chest pain, extreme fatigue
what should you do if a pt experiences signs of distress during a stress test
stop the test and notify the provider
complications of stress testing include
excessive tachycardia, hypotension, arrhythmias
what should be done if a pt has hypotension after a stress test
notify provider and have pt lie supine with legs elevated
define DEXTROCARDIA
heart positioned on right side of chest
the calibration mark is 10 mm high and 10 mm wide, the machine must have used which of the following settings
A) 25 MM/SEC
B) 2 MM/MV
C) 50 MM/SEC
D) 0.5 MM/MV
c) 50 mm/sec
which of the following changes to settings of EKG will double height of tracing
A) 10 MM/MV
B) 25 MM/SEC
C) 20 MM/MV
D) 50 MM/SEC
c) 20 mm/mV
where does the ground lead for 5 lead on holter monitor go
right lower abdomen
where does V5 go on a pt with dextrocardia when doing a 12 lead
right anterior axillary line, fifth intercostal space
