Webster's New World Medical Dictionary

heart conduction system
See 
cardiac conduc-
tion system.
heart failure
See 
congestive heart failure.
heart murmur
An unusual, “whooshing” heart
sound that may be innocent or may reflect disease
or malformation. A heart murmur is created by
blood flow through a heart valve, by blood flow
through a narrowed chamber, or by an unusual
connection between the chambers, as seen with
congenital heart disease. Sometimes a heart mur-
mur does not represent any disease or condition
and is, therefore, referred to as a functional heart
murmur. There are many forms of heart murmurs
representing a variety of heart conditions. Each type
of murmur is characterized by its location, timing,
duration, as well as the intensity and quality of the
sound it makes. A heart murmur is usually heard by
a physician while he or she listens to the chest with
a stethoscope. While the heart murmur itself is
never treated, sometime the condition it represents
may require treatment.
heart rate
The number of heartbeats per unit of
time, usually per minute. The heart rate is based on
the number of contractions of the ventricles (the
lower chambers of the heart). The heart rate may be
too fast (tachycardia) or too slow (bradycardia).
The pulse is a bulge of an artery from waves of
blood that course through the blood vessels each
time the heart beats. The pulse is often taken at the
wrist to estimate the heart rate.
heart septum
The dividing wall between the right
and left sides of the heart. That portion of the septum
that separates the right and left atria of the heart is
termed the atrial, or interatrial, septum, whereas the
portion of the septum that lies between the right and
left ventricles of the heart is called the ventricular, or
interventricular, septum.