L4_Cardiovascular System Disorders
Part IV
Dr. Mickael Joseph
Objectives
• Understand the etiology, pathophysiology,
manifestations, diagnosis and treatment of
valvular defects
Heart Valves
View
ANTERIOR
Transverse plane
Pulmonary valve
Aortic valve
Tricuspid valve
Bicuspid valve
POSTERIOR
Heart Sounds
R
The first sound (S1)
• It can be described as a
lubb sound
• Louder and a bit longer
than S2
• S1 is caused by blood
turbulence associated
with closure of the AV
valves.
T
P
(a) ECG
Q
S
0.1sec
0.3 sec
Atrial
systole
Ventricular
systole
0.4 sec
Relaxation period
Aortic
valve
closes
120
100
Aortic
pressure
80
(b) Pressure
(mmHg)
Left
ventricular
pressure
60
Bicuspid
valve
closes
40
20
Left atrial
pressure
0
(c) Heart sounds
The second sound (S2)
• It can be described as a
dupp sound
• Shorter and not as loud
as S1
• S2 is caused by blood
turbulence associated
with closure of the SL
valves.
S1
S3
S4
End (ventricular) diastolic volume
130
(d) Volume in
ventricle (mL)
S2
60
0
(e) Phases of the
cardiac cycle
Atrial
contraction
Isovolumetric
contraction
Ventricular
ejection
Isovolumetric
relaxation
Ventricular
filling
Atrial
contraction
Valvular Dysfunctions
STENOSIS
INCOMPETENCE
Narrowing of a valve
Failure of a valve to close
Restricts the forward of blood
Allow blood to regurgitate
Valvular Dysfunctions
STENOSIS
INCOMPETENCE
Example: Aortic Stenosis
Heart Sounds
• Normal heart sound: S1
S2
• Systolic murmur: S1
• Diastolic murmur: S1
S2
S2
S1
Clinical Manifestations
Manifestation
Aortic stenosis
Mitral stenosis
Aortic
regurgitation
Mitral
regurgitation
Most common
cause
Congenital
bicuspid valve
Rheumatic heart
disease
Infective
endocarditis
Mitral valve
prolapse
Cardiovascular
outcome
(untreated)
Pulmonary effects
Heart sound
Pulmonary edema: Pulmonary edema: Pulmonary edema: Pulmonary edema:
dyspnea on
dyspnea on
dyspnea on
dyspnea on
exertion
exertion
exertion, _______, exertion
nocturnal dyspnea,
pulmonary
hypertension
murmur
murmur
murmur
murmur
Aortic Stenosis. Mild
stenosis in valve leaflets
of a young adult.
Mitral Stenosis with Classic “Fish Mouth”
(Arrows) Orifice.
Treatment
• Surgical replacement by
mechanical, animal (porcine) or
tissue engineered valves is
often done