Book of Medical Disorders in Pregnancy - Tintash

there is 60 per cent reduction in function
of the valve no significant hemodynamic
changes will be evident.
The Left atrial pressure is increased
which is necessary to overcome the
obstruction of stenosed valve. This increased
pressure is reflected in the
pulmonary bed veins, arteries and capillaries
with symptoms of congestion, and
is characterized by dyspnea, cough,
hemoptysis, and pulmonary edema.
When the orifice of the mitral
valve is only one third of its normal size
the left auricular pressure rise cannot
over come this resistance and eventually
leads to right ventricular hypertrophy.
The cardiac output falls, as a result. In
mitral valve disease there is an increase
in blood volume which causes increase
in venous return and cardiac output.
When mitral disease is long standing it
leads to pulmonary artery sclerosis. This
increases the pulmonary artery pressure
out of proportion to the increase in left
atrial pressure and eventually leads to
right heart failure.
Severe mitral stenosis:
When stenosis of the mitral valve is
severe left atrial and pulmonary
hypertension develops. This is further
aggravated by pregnancy, because of
increase in the cardiac output, blood
volume, and the circulation time. When
cardiac output is increased in the
presence of severe stenosis the pressure
behind the stenosed valve increases
further.
Classification:
Various classifications have been
advanced to grade the severity of heart
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disease. The most common one used today
is the New York classification. This
is based on the functional status of the
patient. It takes into consideration
etiological factors, anatomical status of
the lesions, physiological state of the
patient and functional capacity of the
heart.
Classification of blood pressure
Category SBP MMHG
DBP MMHG
Normal
Prehypertension
Hypertension Stage 1
Hypertension Stage 2