Cardiovascular System: Parts of an EKG

waves to go up the isoelectric baseline

positive deflection

waves to go down the isoelectric baseline

negative deflection

P, R, T are positive deflection or negative deflection?

Positive Deflection

Q, S are positive deflection or negative deflection?

Negative Deflection

This wave in ECG represents Atrial depolarization, the electrical activity that initiates right and left atria to contract, causing blood to be pushed into their respective ventricles, filling them.

P wave

This wave represents the moment the SA node initiates an electrical impulse that depolarizes the right atrium, while Bachmann’s bundle relays the impulse to the left atrium, depolarizing it as well. The depolarization of both atria is shown as the this wave on the ECG, and atrial contraction follows shortly after.

P Wave

This wave represent ventricular depolarization

QRS Complex

This wave in the ECG represents interventricular septum depolarization which begins in the left bundle branch and spreads from left side of the septum to the right side

Q wave

This wave in ECG represent depolarization of the main mass of the ventricles

R wave

This wave in ECG represent last phase of ventricular depolarization, which is the moment where electric conduction reaches the remaining posterior and superior portion of the ventricles through the use of Purkinje fibers to conduct the electrical conduction, completing the ventricular depolarization

S wave

Atrial Repolarization occurs, but obscured by what ECG waves?

QRS Complex

This segment in ECG reflects the plateau in myocardial action potential, and also the moment that ventricles contract and pump blood

S - T Segment

This wave in ECG represent represents ventricular repolarization immediately before ventricular relaxation or ventricular diastole

T Wave

This segment in ECG reflects the time it took for electrical impulse to reach from SA Node to Atrioventricular Node

P - Q Segment

This interval marks the start of Atrial depolarization to the start of ventricular depolarization

PR Interval

This interval marks the start of ventricular depolarization and end of ventriuclar repolarization

Q - T Interval