CHAPTER 6/ Cardiovascular Conditions^93
in place between the chambers of the heart to prevent blood flow backward
into the chamber after being pushed forward. The contraction of heart muscle
is regulated by an electrical system that controls the speed at which the heart
beats. If the tissues of the body require additional oxygen, the heart rate is
increased.
Congestive Heart Failure
What Went Wrong?
Congestive heart failure (CHF) is the inability or failure of the cardiovascular
system to provide adequate cardiac output to meet the metabolic demand of
the body. CHF usually occurs secondary to congenital heart defects in which
there are structural abnormalities leading to increased pressure or volume load
to the ventricles.
1
Aorta
Superior
vena cava
Pulmonary
valve
Right
atrium
lnferior
vena cava
Right ventricle Papillary muscles
Orifices of
coronary
arteries
Left ventricle
Aortic valve
Mitral valve
Left atrium
Pulmonary trunk
Tricuspid
valve
FIGURE 6-2A