CVS 3

Flashcards covering the electrical activity of cardiac muscle cells, contraction and the electrocardiogram.

SA Node

Generates the electrical signal in cardiac muscle cells.

Gap Junctions

Allows electrical signals to spread between cardiac muscle cells.

Depolarization

Rapid influx of Na+ and Ca2+ ions.

Plateau Phase

Maintained by the balance of K+ efflux and Ca2+ influx.

Repolarization

Primarily due to K+ efflux.

Ca2+

Binds to troponin, initiating muscle contraction.

Cardiac Muscle Contraction

Electrical event (action potential) followed by mechanical event (contraction).

Electrocardiogram (ECG)

Records the electrical activity of the heart.

P Wave

Represents atrial activation/depolarization.

QRS Wave

Represents ventricular activation/depolarization.

T Wave

Represents ventricular relaxation/repolarization.

P-R Interval

Time between atrial activation and ventricular activation.

Q-T Interval

Duration of ventricular changes.