CORONARY CIRCULATION Dr.Mohammed Sharique Ahmed Quadri Assistant professor Al Maarefa College 1.
CARDIOVASCULAR SYSTEM CARDIAC CYCLE-II HEART SOUNDS 1 DR. Mohammed Sharique Ahmed Quadri.
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Transcript of CARDIOVASCULAR SYSTEM CARDIAC CYCLE-II HEART SOUNDS 1 DR. Mohammed Sharique Ahmed Quadri.
CARDIOVASCULAR SYSTEM CARDIAC CYCLE-IIHEART SOUNDS
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DR. Mohammed Sharique Ahmed Quadri
Ventricular Systole0.3 sec.
Ventricular Diastole0.5 sec.
Ventricular Systole0.3 sec.
Isometric contraction phase Ejection phase
Isometric Relaxation phase
Rapid inflow phaseDiastasis
Atrial Systole
Cardiac cycle time = 0.8 Sec. (if the heart rate is 75 beats/min.)
Systole Diastole Systole
Phonocadiogram
Electrocardiogram
Ventricular volume
Ventricular pressure
120
80
0
Cardiac cycle
P
Q
R
S
T P
Q
R
S
T
1st 2nd 3rd
Aortic pressure
Systole Diastole Systole
Atrial pressurea c va c v
Events of cardiac cycle
Mitral valve closes
Aortic valve opens
Aortic valve closes
Mitral valve opens
Relationship between Lt. ventricular volume & pressure changes
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Pressure changes during cardiac cycle9
Rt- Atrium = 0-7mm Hg.
Lt- Atrium = 2-10 mm Hg.
Rt – Ventricle = 25 / 6(2-8) mm Hg.
Lt – ventricle = 120 / 8(2-10) mm Hg.
Aorta = 120 / 80 mm Hg.
Pul. Artery = 25 / 10 mm Hg.
• Ejection fraction (EF) is the percentage of ventricular end diastolic volume (EDV) which is ejected with each stroke.
EF =
10
SV (EDV – ESV)
EDVX 100
75
120X 100 = 62.5%
Normal ejection fraction is about 60 – 65 %.
Ejection fraction is good index of ventricular function.
HEART SOUNDS
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• There are four heart sounds SI, S2, S3 & S4.• Two heart sound are audible with stethoscope S1
& S2 (Lub - Dub).• S3 & S4 are not audible with stethoscope Under
normal conditions because they are low frequency sounds.
• Ventricular Systole is between First and second Heart sound.
• Ventricular diastole is between Second and First heart sounds.
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First heart sound (S1)
• It is produced due to the closure of Atrioventricular valves (Mitral & Tricuspid)
• It occurs at the beginning of the systole and sounds like LUB
• Frequency:50-60 Hz • Time: 0.15 sec
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Second heart sound (S2)
• It is produced due to the closure of Semilunar valves (Aortic & Pulmonary)
• It occurs at the end of the systole and sounds like DUB
• Frequency:80-90 Hz [ High pitch ]• Time: 0.12 sec• It is short and sharp
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HEART SOUNDS
• Important • Sounds are caused by vibrations set within
the wall of the ventricles and major arteries during valve closure .
• Opening of the valve does not cause sound.
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Third heart sound (S3)• It occurs at the beginning of middle third of
Diastole• Cause of third heart sound – Rush of blood
from Atria to Ventricle during rapid filling phase of Cardiac Cycle. It causes vibration in the blood
• Frequency:20-30 Htz• Time: 0.1 sec
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Fourth heart sound (S4)or Atrial Sound
• It occurs at the last one third of Diastole • (just before S1)• Cause of Fourth heart sound – Due to Atrial contraction
which causes rapid flow of blood from Atria to noncompliant Ventricle and vibration in the blood.
• Frequency: < 20 Htz• Note:• Third and Fourth heart sound are low pitched sounds
therefore not audible normally with stethoscope• S3 may be heard in children and young adults but
usually pathological in old age17
AD AS
VS VD
EVENTS
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HEART SOUNDS
0.7 Sec. 0.1 sec.
0.3Sec. 0.5 sec.
1 st Heart Sound 2 nd Heart Sound 3 rd Heart Sound 4 th Heart Sound
AS – Atrial Systole; AD – Atrial Diastole ; VS – Ventricular systole; VD – Ventricular diastole
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Heart Murmurs
• Murmurs are abnormal sounds produced due to turbulent blood flow through abnormal heart valves e.g.. stenosis or incompetence.
• Stenosis means narrow or stiff, valve that does not open completely.
• Incompetent means valve which does not close properly and remains open.
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Heat Murmurs• When blood is forced through stenotic valve,
it produces an abnormal whistling sound.• When blood flows backward through
incompetent valve, it produces swishing or gurgling murmur sound.
• Most common cause of stenosis and incompetent valve is Rheumatic fever, an auto immune disease triggered by Streptococcus bacterial infection.
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Heat Murmurs• Systolic murmur are produced during the
systole of the ventricle, between 1st and 2nd heart sound (Lub – Murmer – Dup).
• Diastolic murmur are produced during the diastole of the ventricle, between 2nd and 1st heart sound (Lub – Dup – Murmer – Lub).
• During aortic stenosis and mitral incompetence – systolic murmur.
• Aortic incompetence and Mitral Stenosis – diastolic murmur.
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THANK YOU
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