EKG- KAYE'S CLASS

the instrument used to record the electrical activity of the heart. 

An EKG (ECG) is a tracing/recording of the electrical activity of the heart

• -Can be used in many different healthcare settings
• -Can be transmitted over a phone
• -Ability to monitor electrical conduction of the heart
• -It’s simple, painless & noninvasive

• -Disorders in heart rate or rhythm and the conduction system
• -Presence of electrolyte imbalance
• -Condition of the heart prior to defibrillation
• -Assessment of damage during/after a myocardial infarction (MI)
• -Symptoms related to cardiovascular disorders (weakness, CP, SOB)
• -Diagnosis of certain drug toxicity
• -Assessment of the effects of cardiotoxic or antiarrhythmic therapy
• -Diagnosis of metabolic disorders such as hyper (or hypo)kalemia, hyper (or hypo)calcemia, hyper (or hypo)thyroidism, acidosis and alkalosis
• -Heart condition prior to surgery for individuals at risk for undiagnosed or asymptomatic heart disease
• -Damage assessment following blunt or penetrating chest trauma or changes after trauma or injury to the brain or spinal cord
• -Suspicion of congenital heart disease Assessment of pacemaker function

▪A network of conducting tissue that creates the heartbeat and establishes a pattern for the electrical activity of the heart.

▪Several unique qualities of the conducting tissues of the heart control the beat of the heart to produce & control the electrical wave.

Automaticity, excitability, conductivity, contractility, myocardial cells

Electrical impulses occur at a rate of 60-100 BPM (Avg. HR = 72 BPM with an average of 5 liters of blood pumped per minute)

Delays the electrical impulse to allow for the atria to complete their contraction and ventricles to fill before the next contraction

Conducts electrical impulses from the atria to the ventricles

Conducts impulses down both sides of the IVS

Distributes the electrical impulses through the right and left ventricles, which stimulates the heart muscle to contract.

1)Sinoatrial Node

2)Atrioventricular Node & the bundle of His (aka AV Bundle)

3)The Bundle Branches

4)Purkinje Fibers

• ▪Polarization
• ▪Depolarization
• ▪Repolarization
• ▪Isoelectric
• ▪Interval
• ▪Segment
• ▪Complexes

appearance: Upward small curve

heart activity: Atrial depolarization with resulting atrial contraction

appearance: Q, R, and S waves

heart activity: Ventricular depolarization and resulting ventricular contraction

(larger than the P wave); atrial repolarization occurs (not seen)

appearance: Small upward sloping curve

heart activity: Ventricular repolarization

appearance: Small upward curve

heart activity: Repolarization of the bundle of His and Purkinje fibers (not always seen)

appearance:P wave and baseline prior to QRS complex

heart activity: Beginning of atrial depolarization to the beginning of ventricular depolarization

• appearance: QRS complex, ST segment, and
• T wave

heart activity: Period of time from the start of ventricular depolarization to the end of ventricular repolarization

•  appearance: End of QRS complex to the
• beginning of T wave

 heart activity: The time between ventricular depolarization and the beginning of ventricular repolarization

• -Find the R waves.
• -Look at the QRS duration.
• -Look at the R-R interval.
• -Look for P preceding each R wave.
• -Check the PR interval.

1. Heart rate using R-R interval

2. Heart rate using the 1500 method

When running an ECG strip with a speed of 22 mm/sec there will be 300 large boxes in 1 minute frame. SO...To estimate the heart rate count the number of large boxes between the two R waves in a regular rhythm, and divide into 300.

Most accurate in a regular rhythm. In a 1 minute time frame there are 1500 small squares. So... Count the number of small squares between the R waves and divide 1500 by that number.