Cardiac Cycle

Question 1

preceded by P wave
NOT essential for ventricular filling
a wave - INC in atrial pressure
4th heart sound - d.t. atria contractinh against STIFFF VENTRICLES (LV hypertrophy)

Answer 1

I - ATRIAL SYSTOLE (CONTRACTION)

Question 2

begins during QRS complex
c wave
1st heart sound
closed aortic valve

Answer 2

II - ISOVOLUMETRIC VENTRICULAR CONTRACTION

Question 3

atrial FILLING
VENTRICULAR PRESSURE > atrial pressure
OPEN aortic valves
MOST of the SV is EJECTED
onset of T wave

Answer 3

III - RAPID VENTRICULAR EJECTION

Question 4

Ejection of blood from ventricle continues but is slower
Ventricular pressure begins to decrease
Aortic pressure also decreases

Answer 4

IV - REDUCED VENTRICULAR EJECTION

Question 5

Complete repolarization of ventricles (end of T wave)
CLOSURE OF AORTIC VALVES
S2
Inspiration delays closure of the pulmonic valve —> SPLITTING OF THE 2nd HEART SOUND (physiologic)
AORTIC PRESSURE > ventricular pressure
DICROTIC NOTCH or INCISURA - bli in the aortic pressure occurs AFTER closure of aortic valve
MOST EVENTS HAPPEN HERE

Answer 5

V - ISOVOLUMETRIC VENTRICULAR RELAXATION

Question 6

ATRIAL PRESSURE > ventricular pressure
OPEN MITRAL VALVE
S3 - normal in children; pathologic in adults

Answer 6

VI -RAPID VENTRICULAR FILLING

Question 7

LONGEST phase of cardiac cycle

ventricular filling continues BUT slower rate

Answer 7

VII - REDUCED VENTRICULAR FILLING (DIASTASIS)