Cardiac Cycle/Heart Sounds

Question 1

SA node

Answer 1

Pacemaker of the heart; faster to reach threshold than AV node

Question 2

P wave

Answer 2

atrial depolarization

Question 3

PR interval

Answer 3

Pause between depolarization of atria and ventricles

Question 4

QRS complex

Answer 4

Ventricular depolarization

Question 5

T wave

Answer 5

Ventricular repolarization

Question 6

Systole

Answer 6

Contraction of heart

Question 7

Diastole

Answer 7

Relaxation of heart

Question 8

S1

Answer 8

“Lub”; associated with AV valve closure

Question 9

S2

Answer 9

“Dub”; associated with closure of aortic/pulmonic valves

Question 10

S3

Answer 10

Rapid filling of blood to ventricle (usually not heard in adults); occurs in early diastole

Question 11

S4

Answer 11

Last bit of blood squeezing into ventricle during atrial contraction (not usually heard); occurs in late diastole

Question 12

Systolic murmurs

Answer 12

Due to atrial regurgitation or aortic/pulmonary stenosis

Question 13

Diastolic murmurs

Answer 13

Due to aortic regurgitation or ventricular stenosis

Question 14

What ECG wave occurs when sodium influx is occurring in atrial myocytes?

Answer 14

P wave