EKG and Cardiovascular Flashcards
Somatic tremor (artifacts)
Related to muscle movement. Characterized by irregular, jagged peaks with a shifting baseline throughout the tracing.
AC interference (artifacts)
Characterized by irregular spikes and is related to poor grounding or external electricity interfering with the tracing.
Wandering baseline (artifacts)
The baseline will wander away from the center of the paper. Results from poor electrode connection, can be associated with lotions, oils, or powders on the skin.
Interrupted baseline (artifacts)
Usually related to a disconnected or broken lead wire.
When there is a break in the tracing or the tracing moves into the margins of the paper.
P Wave (waveform)
Represents atrial depolarization or contraction
QRS (waveform)
Represents ventricular depolarization or contraction (atrial repolarization is not visible but occurs during this phase)
T Wave (waveform)
Represents ventricular repolarization or relaxation
U Wave (waveform)
Represents a repolarization of the bundle of His and Purkinje fibers.
Not always visible
P-R interval (intervals)
Represents the time it takes from the beginning of atrial depolarization to the beginning of ventricular depolarization.
Starts at the beginning of P Wave and ends at the beginning of the Q wave.
QT interval (interval)
Represents the time it takes from beginning of ventricular depolarization to the end of ventricular repolarization.
Starts at the beginning of the Q wave and ends at the end of the T wave.
ST segment (segment)
Represents the time from the end of ventricular depolarization to the beginning of ventricular repolarization.
Starts at the end of S wave and ends at the beginning of the T wave.
What should the speed be set on for an EKG machine?
25 mm/second
What leads are bipolar?
Lead l - records impulses L./R. Arms
Lead ll - records impulses R. Arm/L. Leg
Lead lll - records impulses L. Arm/L. Leg
Makes up the Einthovin’s Triangle
What leads are augmented?
Leads AVL, AVR, AVF
Sinoatrial node (SA)
Natural pacemaker of the heart, located in the upper right atrium
Atrioventricular node (AV)
Secondary pacemaker, located at the junction of the atria and the ventricles.
What leads are precordial and unipolar?
Leads V1, V2, V3, V4, V5, V6
You notice a widened QRS complex on the EKG strip, what is a possible cause of this type of artifact?
Premature ventricular contraction
Is caused by an early contraction of the ventricles that produce a widened QRS complex artifact
Pulmonary circuit (heart)
Forms a closed circuit between the heart and lungs.
Upper part of the body
Systemic circuit (heart)
Carries blood away from the heart
Lower part of the body
Interventricular septum (heart)
Separates the left & right ventricles
Left atrium (heart)
Receives oxygenated blood from the lungs and empties into the left ventricle.
Semi-lunar valves (heart)
Determines the passage of blood between ventricles & main arteries
Helps maintain pressure on major arteries
Prevents back flow from atrials to ventricles during ventricular diastole
Aorta (heart)
Largest artery
Distributes oxygenated blood to all parts of the body
Originating from the left ventricle & extending down to the stomach
Atrioventricular valve (mitral/bicuspid) (heart)
Prevent blood from flowing backwards as it moves through the heart
2 flaps - left side of heart
Atrioventricular valve (tricuspid) (heart)
Separates atria from ventricles
Prevent backflow of blood from the ventricles into the atria during systole
3 flaps - right side of heart
Pulmonary veins (heart)
Veins that transfer oxygenated blood from the lungs to the heart
Pulmonary arteries (heart)
Artery in pulmonary circulation that carries deoxygenated blood from the right side of the heart to the lungs
Inferior vena cava (heart)
Large vein that carries deoxygenated blood from the lower & middle body into the right atrium
Left ventricle (heart)
Pumps oxygenated blood to the aorta/body
Right ventricle (heart)
Pumps blood to the pulmonary artery to become oxygenated
Right atrium (heart)
Receives deoxygenated blood from the body through the vena cava then pumps into the right ventricle
Superior vena cava (heart)
Returns deoxygenated blood from the upper portion of the body to the right atrium
Blood flows? (heart)
Same direction as decreasing pressure
Arteries -> capillaries -> veins
Arteries (heart)
Begins with aorta
Carries oxygen rich blood away from the heart & to the bodies organs
Veins (heart)
Carries deoxygenated blood back to the heart through the vena cava’s
What directions should the electrodes be facing on the body?
Downward on chest
Downward on arms
Upwards on legs
You are preparing to calculate a pt’s heart rate from an EKG tracing. What method should you use?
You should use the 1,500 method to calculate one cardiac cycle.
Divide 1,500 by the number of small boxes between two R waves
What instructions should you give a patient wearing a Holter monitor?
- Avoid using electric blankets
- Take sponge baths
- Wear the monitor for 24-48 hrs
- continue daily activities
