| Question | Answer |
| What are the 3 parts of Ventricular Systole? | 1.Isovolumetric contraction.
2.Rapid Ejection.
3.Reduced Ejection.
**All of this is occuring during Phase 2 of the ventricular AP. |
| What are 4 parts of ventricular Diastole? | 1.Isovolumetric relaxation.
2.Rapid ventricular filling.
3.Reduced ventricular filling.
4.Atrial Systole (Pwave). |
| What determines whether or not a heart valve is open or closed? | PRESSURE DIFFERENTIAL |
| What are the 5 main stages of the cardiac cycle? | 1A:Rapid inflow & diastasis.
1B:Atrial systole (P-R interval).
2:Isovolumetric contraction (QRS).
3:Rapid ejection.
4:Isovolumetric relaxation. |
| what wave represents Atrial systole (phase 1b of cardiac cycle)? how long does it take? does it contribute to the LV volume? | represented by the A Wave, it takes ~0.15sec and does NOT change LV volume much (only 10-15ml). LV filling is PASSIVE |
| What valves open/close during atrial systole (phase 1b of cardiac cycle)? what is happening to the MAP? | NO VALVE CHANGE!! the MAP is falling down closer to 80mmHg. |
| Isovolumetric contraction (phase 2 of cardiac cycle) | 1.Valves: Mitral valve closes (initiates).
2.Pressure:rises from 15 to 80mmHg.
3.Volume:No change (EDV, flatline MAX on graph).
4.Sounds:S1 (mitral valve closing).
5.Atrial wave:C wave (mitral valve push into atria).
6.Time:0.05sec.
7.ECG:end of QRS |
| Rapid & Reduced Ejection (phase 3 of cardiac cycle) | 1.Valve:Aortic semilunar opens (initiates).
2.Pressure:rises to PEAK systolic and then declines to 100mmHg.
3.Volume:Decreases from EDV down to ESV.
4.Sounds:none.
5.Atrial wave:V wave (atrial filling).
6.Time:0.3s.
7.ECG:S-T segment. |
| is PEAK systolic pressure at the end or the middle of the ejection phase (3)? | MIDDLE |
| When is the majority of the BL volume pumped out of the LV? | Half way through the Ejection phase (3) |
| Isovolumetric relaxation (phase 4 of cardiac cycle) | 1.Valves:Aortic semilunar closes (mitral valve remains closed).
2.Pressure:Drops from 100 to 0mmHg.
3.Volume:No change (ESV, flatline MINIMUM).
4.Sounds:S2 (aortic closes).
5.Atrial wave:none.
6.Time:0.08s.
7.ECG:T wave |
| When does Isovolumetric relaxation (phase 4) and passive ventricular filling (phase 1a) begin? | when the Mitral valve OPENS (due to LV and LA pressure becoming equal) |
| What does the Dicrotic notch represent? how does MAP remain above 80mmHg? | The SLAMMING SHUT of the aortic semilunar valve.
The elastic energy absorbed by the smooth muscle artery stretch during PEAK systolic pressure is used to maintain pressure |
| Passive ventricular filling (phase 1a of cardiac cycle) | 1.Valves:mitral valve opens (initiates).
2.Pressure:minimal changes.
3.Volume:Rises from ESV almost to EDV.
4.Sounds:S3.
5.Atrial wave: none.
6.Time:0.5s.
7.T-P segment. |
| How are the pressure changes in the R heart compared to the L heart? | Qualitatively similar but Quantatatively less:
1.RV:LV (25/4:120/9).
2.Pulmonary Arteries:Aorta (25/10:120/80). |
| Do the phases of the cardiac cycle decrease equally as HR increases? | NO.
Low HR (60bpm): Diastole is 2X longer.
High HR (180bpm): Diastole is 1/2 systole (which will decrease EDV) |
| Average time spent in ventricular systole? (phases 2&3) | 0.35 seconds. (0.3sec is phase 3) |
| Average time spent in ventricular diastole? (phases 1a&1b&4) | 0.73 seconds (0.5sec is phase 1a) |
