EKG Final

EKG (Electrocardiogram)

A non-invasive test that records the electrical activity of the heart, providing information about heart rate, rhythm, and abnormalities.

P Wave

Represents atrial depolarization (contraction) in an EKG.

PR Interval

The time from the beginning of the P wave to the beginning of the QRS complex, representing atrial depolarization and AV node delay. Normal duration is 0.12 - 0.20 \text{ s}

QRS Complex

Represents ventricular depolarization (contraction) in an EKG.

ST Segment

The time from the end of ventricular depolarization to the beginning of ventricular repolarization, normally isoelectric.

T Wave

Represents ventricular repolarization (relaxation) in an EKG.

QT Interval

Total time for ventricular depolarization and repolarization, varying with heart rate.

Bradycardia

A heart rate that is below 60 \text{ bpm}

Tachycardia

A heart rate that is above 100 \text{ bpm}

Sinus Rhythm

The normal cardiac rhythm originating from the SA node, with a rate of 60-100 \text{ bpm} and consistent P-QRS-T complexes.

Sinus Bradycardia

A cardiac rhythm originating from the SA node with a rate of less than 60 \text{ bpm}, with consistent P-QRS-T complexes.

Sinus Tachycardia

A cardiac rhythm originating from the SA node with a rate of greater than 100 \text{ bpm}, with consistent P-QRS-T complexes.

Atrial Fibrillation (AFib)

A chaotic atrial rhythm where the atrial rate is very rapid and unmeasurable, resulting in an irregularly irregular ventricular rhythm and absent P waves.

Premature Ventricular Contraction (PVC)

A premature, wide, and bizarre QRS complex that is not preceded by a P wave, often followed by a compensatory pause.

First-Degree AV Block

Characterized by a prolonged PR Interval (>0.20 \text{ s}) where all P waves are still followed by a QRS complex.

EKG (Electrocardiogram)

A non-invasive test that records the electrical activity of the heart, providing information about heart rate, rhythm, and abnormalities.

P Wave

Represents atrial depolarization (contraction) in an EKG.

PR Interval

The time from the beginning of the P wave to the beginning of the QRS complex, representing atrial depolarization and AV node delay. Normal duration is 0.12 - 0.20 \text{ s}

QRS Complex

Represents ventricular depolarization (contraction) in an EKG.

ST Segment

The time from the end of ventricular depolarization to the beginning of ventricular repolarization, normally isoelectric.

T Wave

Represents ventricular repolarization (relaxation) in an EKG.

QT Interval

Total time for ventricular depolarization and repolarization, varying with heart rate.

Bradycardia

A heart rate that is below 60 \text{ bpm}

Tachycardia

A heart rate that is above 100 \text{ bpm}

Sinus Rhythm

The normal cardiac rhythm originating from the SA node, with a rate of 60-100 \text{ bpm} and consistent P-QRS-T complexes.

Sinus Bradycardia

A cardiac rhythm originating from the SA node with a rate of less than 60 \text{ bpm}, with consistent P-QRS-T complexes.

Sinus Tachycardia

A cardiac rhythm originating from the SA node with a rate of greater than 100 \text{ bpm}, with consistent P-QRS-T complexes.

Atrial Fibrillation (AFib)

A chaotic atrial rhythm where the atrial rate is very rapid and unmeasurable, resulting in an irregularly irregular ventricular rhythm and absent P waves.

Premature Ventricular Contraction (PVC)

A premature, wide, and bizarre QRS complex that is not preceded by a P wave, often followed by a compensatory pause.

First-Degree AV Block

Characterized by a prolonged PR Interval (>0.20 \text{ s}) where all P waves are still followed by a QRS complex.

Second-Degree AV Block, Type I (Wenckebach/Mobitz I)

Progressively prolonged PR interval until a QRS complex is dropped, followed by a cycle restart.

Second-Degree AV Block, Type II (Mobitz II)

Characterized by a consistent PR interval but with occasional P waves that are not followed by a QRS complex (intermittent dropped beats).

Third-Degree AV Block (Complete Heart Block)

A severe block where no atrial impulses are conducted to the ventricles; atria and ventricles beat independently (P waves and QRS complexes are dissociated).

Ventricular Tachycardia (VT)

A rapid heart rhythm originating from the ventricles, characterized by wide QRS complexes (>0.12 \text{ s}) and a rate typically over 100 \text{ bpm}. Can be life-threatening.

Ventricular Fibrillation (VFib)

A chaotic and disorganized electrical activity in the ventricles, resulting in no discernible P waves, QRS complexes, or T waves on EKG. Leads to immediate circulatory collapse and requires immediate defibrillation.

Agonal Rhythm

A very slow and erratic rhythm (<20 \text{ bpm}), often seen in a dying heart, indicating severe myocardial compromise.

Asystole

Complete absence of electrical activity in the heart, appearing as a flat line ("flatline") on the EKG. Indicates cardiac arrest.

ST-Elevation Myocardial Infarction (STEMI)

An acute myocardial infarction characterized by significant ST-segment elevation on the EKG, indicating full-thickness myocardial injury (transmural ischemia).

Non-ST-Elevation Myocardial Infarction (NSTEMI)

An acute myocardial infarction without persistent ST-segment elevation, often presenting with ST-segment depression or T-wave inversions on the EKG, indicating partial-thickness myocardial injury.

Heart Rate Calculation: 300-150-100-75-60-50 Method

A method to quickly estimate heart rate by counting the number of large squares between two consecutive R waves. Start from a thick line with an R wave and count 300, 150, 100, 75, 60, 50 for each subsequent thick line.

Heart Rate Calculation: 6-Second Method

A method to calculate heart rate by counting the number of QRS complexes in a 6-second strip (which spans 30 large squares on standard EKG paper) and multiplying that count by 10. This method is especially useful for irregular rhythms.

Pulse Point: Radial

Location on the thumb side of the wrist where the radial artery pulse can be palpated.

Pulse Point: Carotid

Location bilaterally on the neck, lateral to the trachea, where the carotid artery pulse can be palpated.

Pulse Point: Brachial

Location on the medial aspect of the antecubital fossa (inner elbow) or mid-arm, often used for blood pressure measurement in adults and pulse checks in infants.

Pulse Point: Femoral

Location in the groin area, midway between the pubic bone and the anterior superior iliac spine, where the femoral artery pulse can be palpated.

Pulse Point: Popliteal

Location behind the knee in the popliteal fossa, where the popliteal artery pulse can be palpated.

Location on the top (dorsum) of the foot, lateral to the extensor hallucis longus tendon, where the dorsalis pedis artery pulse can be palpated.