The cardiac cycle Flashcards
What are 4 distinct phases of cardiac cycle?
1) Ventricular filling
2) isovolumetric ventricular contraction
3) ventricular ejection
4) isovolumetric ventricular relaxation
What is Mid/late diastole
ventricular filling
What is Systole?
isovolumetric ventricular contraction
ventricular ejection
What is early diastole?
isovolumetric ventricular relaxation
What happens in ventricular filling?
atrial depolarisation so contracts
What is isovolumetric ventricular contraction ?
pressure in ventricles rise
isovolumetric= same volume
What is ventricular ejection ?
increased Aortic pressure
What is isovolumetric ventricular relaxation?
atrial filling
What does isovolumetric contraction mean?
Ventr. contract but not pressure not enough to open Semi lunar valves so volume is the same
What does isovolumetric relaxation mean?
Ventr. relax and all valves are shut and same vol.
What is aortic diastole pressure?
SL valves closed and pressure drops
what is aortic systolic pressure?
Max pressure increase
what is mean arterial pressure?
average cardiac pressure
What causes dicrotic notch on aortic pressure graph?
Aortic valve shutting
What is pulse pressure? PP
Systolic pressure minus diastolic pressure
What is Mean arterial pressure ? MAP
Diastolic pressure + 1/3 * Pulse pressure
What is Stroke volume? SV
End diastolic volume minus end systolic volume
What is ejection fraction ? EF
SV/ EDV
What is ejection fraction?
vol of blood ejected in 1 beat: vol of blood prior to ejection
What is EF is 50%?
every heart beat 50% of blood is ejected from heaert
What is lub sound
AV Valves closing
What is dub sound?
pulmonary and semi lunar valves closing
How are sounds formed ?
from laminar to turbulent flow
What is coronary artery disease?
accumulation of atherosclerotic plaque
what does Coronary artery disease lead to?
myocardial infarction
angina
What are risk factors for CAD?= DISCPOG
Diabetes Inactive Smoking Cholesterol Blood pressure obesity Genes
What are procedures for CAD?
Streptokinase- break blood clots
angioplasty- stent
Bypass graft- use saphenous vein from leg to bypass artery
What is congenital heart disease?
Acyanotic
Cyanotic
What is acyanotic ?
normal level of 02#
What is cyanotic?
low 02 so dark blood
What is septal defects?
blood flow from left to right of heart so blood mix
What is coarctation of aorta?
narrow aorta so blood pressure rises
What is patent ductus arteriosus?
blood from aorta mix with de02 blood from pulmonary artery
What is characteristic of patent ductus arteriosus?
vessel between aorta and pulmonary artery so increase aortic trunk blood pressure
