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Cardiology: Clinical examination, Cardiac cycle

    Clinical examination:

    • We usually begin by measuring vital signs: awareness, general Situation, orientation of time and place, and checking pulse (in the four limbs, Checking pulse over the carotid artery)
    • Number of breathing times and O2-saturation.
    • Temperature measurement.
    • Measuring arterial pressure.
    The cardiovascular examination includes three components: inspection, palpation and auscultation.

    General inspection:

    • Should be done from head to foot, here should pay attention to the special Facies, which appear in some syndromes.
    Examples:

    Syndrome Cardiac defect
    hereditary telangiectasia syndrome pulmonary arteriovenous fistula
    LEOPARD syndrome (abnormalities of the skin, heart, inner ears, and genitalia) pulmonal stenosis
    Paget's disease arteriovenous shunt
    Nail clubbing Cyanotic heart defect / Endocarditis
    Down Syndrome Endocardial Cushion Defect (VSD + ASD) and Tetralogy of Fallot
    Noonan's syndrome Supravalvular or subvalvular  pulmonary stenosis
    Williams syndrome supravalvular aortic stenosis
    Turner syndrome Aortic Isthmus stenosis
    Behçet's disease uveitis

    • Symmetry: congenital pulmonary arteriovenous fistula may be associated with asymmetry of the face.
    • The edema (face, neck, collateral circulation in the upper section of the chest wall) may refer to Superior vena cava syndrome
    • Neck symmetry
    • lymphadenopathy
    • collateral circulation in the upper section of the chest wall
    • heart auscultation points, especially Cardiac Apex Beat
    • Chest symmetry and form: (The left part of the chest is convex: often Congenital Heart Defects, called Cushion Defect)
    • Lateral circulation in the lower chest and upper abdomen
    • abdominal inspection, limbs, then spine (kyphosis, scoliosis, straight back associated with mitral valve prolapse)

    Cardiac cycle



    Cardiac_cycle
    Source: www.wikipedia.org

    First: Ventricular diastole phase:Duration of 0.5 seconds)
    Ventricular diastole passes through five phases:
    1. Isovolumic relaxation phase: (all valves) are closed.
    2. Rapid-filling inflow phase (passive): where the mitral valve opens and 80% of the blood flows from the atrium to the ventricle.
    3. Slow-filling phase: where 5% of the blood flows from the atrium to the ventricle.
    4. Balance in pressure and non-flow phase: where the pressure between the atria and the ventricle is equal and blood does not flow.
    5. Atrial systole phase (Active): 15% of the blood flows from the atrium to the ventricle
    Second: ventricular systole phase: (Duration of 0.3 seconds)
    1. Atrial contraction increases the pressure in the ventricle thus mitral valve closes (the first sound), and the aortic valve here has been closed since the beginning of diastole, here the ventricle becomes a closed chamber (Isovolumic contraction)
    2. In the next phase, the pressure in the left ventricle increases at a speed of "120 mmHg" until it becomes greater than the pressure within the aorta. "80 mmHg The aortic valve opens and the ventricular systole phase begins and the blood flows from the left ventricle to the aorta.
    3. The ventricular pressure gradually decreasesWhen the pressure in the aorta becomes higher than the pressure in the left ventricle, the aortic valve closes (the second sound S2). At this time the mitral valve is still closed and the ventricle becomes a closed chamber again. This isovolumic relaxation phase
    4. With ventricular diastole, the pressure in the ventricle decreases until it is lower than the pressure in the left atrium (which is full) and the mitral valve opens, and so on.
    Phases_of_the_Cardiac_Cycle
    Source: www.wikipedia.org
    Briefly :
    The contraction period is a fixed period, and the relaxation period is longer, so in case of tachycardia it occurs at the expense of the relaxation period.
    In relaxation period occurs ventricular filling and coronary perfusion.

    The left side corneal perfusion is done with relaxation, and the right side in contraction and relaxation.

    Atrial contraction passes 15% of the blood naturally, but in the case of heart failure the rate reaches 40% which is very important, as in the absence (for example, in the case of atrial fibrillation) worsens the situation of the patient.

    The third cardiac sound occurs due to the rapid filling of the ventricle followed by a sudden stop (it can be heard in the case of the diastolic heart failure, for example).

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