ventricle-systole
2 larger, lower chambers of the heart. Left ventricle is the major pumping chamber of the heart.
During the systolic phase, the heart muscle contracts, creating pressure to open the pulmonary and aortic valves. Blood from the right ventricle is pushed int
drifting baseline
Wandering baseline shift, occurs when the tracing drifts away form the center of the graph paper. Baseline shift can have many causes. Typically, it is due to improper electrode application such as the following:
Too loose or incorrect electrode applicati
electrodes
are disposable, 12-Lead EKG uses 10 electrodes. Electrodes are small sensors placed on the skin to receive the electrical activity from the heart, and leads are covered wires that conduct the electrical impulse from the electrodes to the EKG machine.
SA node
Sinoatrial (SA) node (pacemaker)
Initiates heart at a rate of 60 - 100 beats per minute with electrical impulse that causes depolarization. Small, round structure that consist of Purkinje fibers, located in right atrium area. 1st item in list for electric
right atrium
A receiving chamber for deoxygenated blood (blood that's had some oxygen removed by the body's tissues) returning to the heart from the body, the right atrium has an oxygen (O2) saturation of only 60% to 75%. Located over right ventricle where deoxygenate
faster the paper the slower the heart will look
and the slower the paper, the faster the heart would look. The paper going through the EKG represents real time. If the EKG speed was changed, this must be noted on the EKG results.
electrode placement V leads
standard limb leads
bipolar leads, standard leads, 1st 3 leads, standard limb leads.
Right Arm, Left Arm, Left Leg
Lead I records RA(-) to LA(+).
Lead II records RA(-) to LL(+).
Lead III records LA(-) to LL (+).
Measures flow of electrical current in 2 directions at the same
bipolar leads
standard leads, 1st 3 leads, standard limb leads.
Right Arm, Left Arm, Left Leg
Lead I records RA(-) to LA(+).
Lead II records RA(-) to LL(+).
Lead III records LA(-) to LL (+).
Measures flow of electrical current in 2 directions at the same time.
atrial depolarization
electrical activiation of the atria. discharge of electrial activity in the upper heart chambers, What happens to produce a P-wave?
P wave
The P wave is seen when the atria depolarize. The P wave is small (compared to the other waves of the EKG), rounded, and is the first wave of the normal complex.
standardization value
On most machines, pressing the standardization control produces a standardization mark. The stylus should move up 10 small squares and remain there for two small squares.
10 mm high or 1 millivolt
or 10 little squares up on EKG paper or 2 big squares up w
AV valves
Atrioventricular valves; Tricuspid and Bicuspid (or Mitral) valves go between atria and ventricles; the tricuspid and mitral valves open when the atrium's pressure is higher than the ventricle's. Blood then flows down from atrium to ventricle
bicuspid
also called mitral valve, an A/V valve leading from the left atrium to left ventricle
tricuspid
an A/V valve leading from the right atrium to right ventricle
heart murmur sound
bruit
QRS segment
Ventricular contraction is QRS complex on EKG.
ventricular contraction
Ventricular contraction is QRS complex on EKG.
V leads
Precordial leads, horizontal across chest, V1, V2, V3, V4, V5, V6
the right atrium receives deoxygenated blood from the superior and inferior venae cavae
True
AVR
Augmented Right Arm Lead. Lead aVR records electrical activity from midway between the left arm and left leg to the right arm. Lead aVR is usually a negative deflection. If it does not produce a negative deflection, you might have the electrodes or lead w
AVL
Augmented Left Arm Lead. Lead aVL records electrical activity from the midpoint between the right arm and left leg to the left arm.
AVF
Augmented Foot Lead. Lead aVF records electrical activity form the midpoint between the right arm and left arm to the left leg.
augmented leads
The second 3 leads are known as augmented leads because their tracings are (augmented) increased in size by the EKG machine in order to be interpreted. They are also known as unipolar leads because they measure toward one electrode on the body. The voltag
horizontal axis-represents time
speed, rate, 0.04 seconds,
25 mm per second
25 little squares or 5 big squares per second.
1,500 small blocks equals 1 minute.
300 big blocks equals 1 minute.
horizontal on EKG paper
each little square is 1 mm
At the normal paper speed, one second equals
vertical axis-represents voltage
gain, height or amplitude
represents volume (contraction)
10 mm = 1 millivolt (mV)
each little square is 1 mm
Two large boxes represents 10 mm, which equals one centimeter (cm). EKG machines must be calibrated so that 1 cm = 1 mV. Each heavy line horizont
ST segment elevation
Ischemia, which is a lack of oxygen to the heart muscle, causes the ST segment to elevate.
An elevated ST segment indicates myocardial damage in the form of injury to the heart muscle.
Need to doublecheck this, did not seem to correspond with test questio
ventricular depolarization
shown by the QRS complex
QRS complex
The QRS waves together form the QRS complex.
The QRS complex represents ventricular depolarization.
It is reflective of the time it takes for the impulses to activate the myocardium to complete contraction from the Purkinje fibers.
bradycardia patient and P wave
bradycardia is essentially normal appearing but slow. Tachycardia may have p waves obscured by the ST segment. Bradycardia and Tachycardia are sinus arrhythmias and the P wave is not affected. The P wave would be affected in Atrial arrhythmias like heart
normal cardiac electrical conduction pathway (electricity route through heart)
The conduction system consists of the 1. sinoatrial (SA) node, 2. atrioventricular (AV) node, 3. Bundle of His (AV bundle), 4. bundle branches, and the 5.Purkinje fibers (network).
AV node
small, round structure that consists of Purkinje fibers. 2nd item in electricity flow 1. sinoatrial (SA) node, 2. atrioventricular (AV) node, 3. Bundle of His (AV bundle), 4. bundle branches, and the 5.Purkinje fibers (network).
repolarization
Is a state of cellular recovery, which follows each contraction. The cardiac cells return to their resting phase of internal negativity. After depolarization, the cardiac cells return to this state in order to prepare for another depolarization. During re
ground electrode
always RL (right leg) Does not gather information.
1, 2, 3
bipolar/standard limb leads
Einthoven is the scientist credited with the developing the first EKG machine. The Einthoven triangle is formed by three of the limb electrodes; those on the right arm, the left arm, and the left leg. The right leg is used only
MI
myocardial infarction (heart attack)
route of blood through heart
Deoxygenated blood: Superior and inferior venae cavae > right atrium > tricuspid valve > right ventricle > pulmonary semilunar valves > pulmonary trunk > Pulmonary arteries > lung tissue(Pulmonary circulation) > Pulmonary veins(oxygenated blood) > left at
to see a fast heart rate better, adjust EKG how?
speed up paper going through
precordial
The last six leads are the chest leads. Also known as precordial, these leads are located in front of (pre) the heart (cor). Unipolar because they are measured in one direction only. Numbered from V1 to V6.
What can cause interrupted baseline?
patient moved
lead fell off
patient coughed
PVC
What can cause somatic tremor?
cold, Parkinson's disease, body tremors. Sometimes a patient's muscles will move, either voluntarily or involuntarily , which can produce somatic tremor, also known as body tremor. Movement of the muscles of the body is controlled by electrical voltages.
What can cause wandering baseline?
breathing
What can cause sixty-cycle interference?
electrical interference
Normal standard =
10 mm high or 1 millivolt
or 10 little squares on EKG paper
or 2 big squares with darker lines on EKG paper
PVC
Premature ventricular contraction
Heart anatomy
Heart anatomy - layers
Heart anatomy - blood flow
bruit
Abnormal sound or murmur heard on auscultation of an organ, vessel, or gland. (f. book)
ventricle-systole
semilunar valves
GO OUT OF VENTRICLES; The aortic and pulmonic valves open when the pressure in the ventricles exceeds that in the aorta and pulmonary artery.
bipolar leads - electrode placement
suprasternal notch
the dip you feel at the base of the neck just above where the clavicle attaches to the sternum
angle of Louis
is a ridge above an inch or so below the suprasternal notch. It is where the main part of the sternum and the manubrium (top of the sternum) attach.
intercostal spaces
To feel the intercostal space, or space between the ribs, locate the sternum. Press your fingers to the of the sternum is known as the sternal border. Between each connected rib you should feel a dip or dent. Feeling as close to the sternal border as poss
midclavicular line
On most patients, the midclavicular line starts in the center of the clavicle and passes vertically through the nipple line.
anterior axillary line
The anterior axillary line starts in the front of the axilla and runs down the left side of the chest.
midaxillary line
The midaxillary line starts in the middle of the axilla (armpit) and runs down the side of the chest.
EKG/ECG paper
EKG paper measurements
10 leads make 12 circuits
The 10 lead wires produce 12 different lead circuits consisting of one or more wires from the electrodes to the electrocardiograph. The 12 leads are made up of three different types of leads; three standard limb leads, three augmented leads, and six chest
PQRST(U) looks like
T wave
The T wave represents ventricular repolarization. As repolarization occurs, the ventricular muscles relax. Normal T waves are in the same direction as the QRS complex and the P wave.
Depolarization
Is a state of cellular stimulation which precedes contraction. It is the electrical activation of the cells of the heart when they lose their internal negativity.
Depolarization moves from cell to cell through the electrical pathways. Depolarization is th
repolarization-chemistry
After depolarization, an electrical wave then moves from cell to cell, spreading this electrical charge throughout the heart.
During cell recovery, sodium and potassium ions are shifted back to their original places by way of the sodium-potassium pump, an
polarized
The polarized state is a state of readiness-the cardiac cell is ready for electrical action. Heart cells, in their resting state are electrically polarized. This means their insides are negatively charged, whereas on the outside, they are positively charg
Depolarization-chemistry
When the cardiac cell is stimulated by an electrical impulse, a large amount of sodium rushes into the cell and a small amount of potassium leaks out, causing a discharge of electricity. The cell becomes positively charged. This is called depolarization.
Mnemonic story: conduction in heart
Grandma watches grandson's cat "Kinje" climb a tree. Cat gets stuck high in branches, but is ok, "Purr." Grandson is upset about his cat. Grandma stops a passerby and says "Saav his Kinje"
Sa : Sinoatrial node/SA node
av : atrioventricular node/AV node
Hi
cardiac conduction-anatomy