The MA is responsible for?
- -Prep of the patient
- -operation of the ECG
- -ID and eliminate artifacts
- -label and chart
- -care of the ECG
Structure of the heart
- 1. blood enters the RIGHT ATRIUM from the SVC and IVC.
- 2. from the RA, blood enters the RIGHT VENTRICLE.
- 3. Picks up oxygen in the lungs and returns to the LEFT ATRIUM.
- 4. Blood enters the LEFT VENTRICLE (most powerful)
- 5. blood exits from the LV and disburses to body.
Conduction system of the heart
SA node-sinoatrial- knot of myocardial cells that have the ability to send out an electrical impulse without an external nerve stimulus.
The SA node....
- Distributes impulses to the right and left atria.
- the impulse is picked up by the AV node.
AV node- Atrioventricular
transmits the impulse to bundle of his.
Bundel of his...
divides into right and left branches, they relay impulse to the purkinje fibers....distribute the pulse evenly to the right and left ventricles.
the cardiac cycle
represents one complete heartbeat.
the ECG cycle...
is the graphic representation of the cardiac cycle.
- P wave- contraction of the atria or atrial depolarization.
- QRS complex-ventricular depolarization.
- T wave-recovery of the ventricles.
flat, horizontal line that seperates the various waves.
portion of the ecg between two waves.
length of a wave.
segments and intervals
heat sensitive and pressure sensitive
- first three leads of the ecg
- I-right arm/left arm
- II- rhythm strip- right arm/left leg
- III-left arm/left leg
- aVR- right arm-
- aVL- left arm
- aVF- left leg/foot
- V1-4TH INTERCOSTAL SPACE AT THE RIGHT MARGIN
- V2- LEFT MARGIN
- V3- MIDWAY BETWEEN 2 AND 4
- V4 -5TH INTERCOSTAL SPACE LEFT MIDCLAVICULAR LINE
- V5- LEFT ANTERIOR AXILLARY LINE.
- V6- LEFT MIDAXILLARY LINE.
- RECORD THE HEARTS VOLTAGE FROM FRONT TO BACK.
- eye contact
- patient is comfortable
- explain everything
- ask to touch
1. muscle- check lead 2 first. fuzzy lines, involuntary and volunatary movement.
2. wandering baseline- loose electrodes, body creams, lotions.
3. 60 cycle- electrical inteference. small spiked lines that are consistent.
characterized by a beat that comes before the next normal beat is due.
common in healthy patients. (caffeine, tobacco)
atrial premature contraction (APC)
an abrupt episode of tachycardia. sudden pounding or fluttering, weakness.
Paroxysmal Atrial tachycardia (PAT)
250-350 beats per min.
rarely occurs in healthy patients. underlying heart disease.
atria are contracting 400-500 bpm. emotional stress, alcohol, vomiting.
caused by anxiety, smoking, alcohol, certain meds.
premature ventricular contraction (PVC)
150-250 bpm. no p waves. life threatning.
most serious. no p waves, qrs complexes, or t waves. result in sudden death.