Cardiovascular Renal Disease Arrhythmia

Categories: Uncategorized
Sources: Disturbances Of The Heart

While this terns really signifies irregularity and intermittence of

the heart, it may also be broadly used to indicate a pulse which is

abnormally slow or one which is abnormally fast, a rhythm which is

trot correct for the age, condition and activity of the patient.

Irregularity in the pulse beat as to volume, force and pressure,

except such variation in the pulse wave as caused by respiration, is

always abnormal. While an intermittent pulse is of course abnormal,

it may be caused in certain persons by a condition which does not in

the least interfere with their health and well-being.

As to whether a slow or a more or less (but not excessively) rapid

pulse in any one is abnormal depends entirely on whether that speed

is normal or abnormal for that person. As a general rule the heart

is more rapid in women than in men. It is always more rapid in

children than in adults, and generally diminishes in frequence after

the age of 60, unless there is cardiac weakness or some cardiac

muscle degeneration. The average frequence of the pulse in an adult

who is at rest is 72 beats per minute, but a frequency of 80 is not

abnormal, and a frequency of 65 in men is common; 60 is infrequent

in men but normal, while up to 90 is not abnormal, especially in

women, at the time the pulse is being counted.' It should always be

considered that in the majority of patients the pulse is slightly

increased while the physician is noting its rapidity. Anything over

90 should always be considered rapid, unless the patient is very

nervous and this rapidity is considered accidental. Anything below

60 is abnormally slow. In children under 10 or 12 years of age,

anything below 80 is unusual, and up to 100 is perfectly normal, at

least at such time as the pulse is counted and the patient is awake.

Referring to the first chapter of this book, it will be noted that

many physiologic factors must enter into the production of the

normal regularity of the pulse. The stimulus must regularly begin in

the auricle, must be perfectly transmitted through the bundle of His

to the ventricles, the ventricles must normally contract with the

normal and regular force, the valves must close normally and at the

proper time, the blood pressure in the aorta must be normally

constant to insure the perfect transmission of the blood to the

peripheral arteries and to insure the normal circulation through the

coronary arteries, and the arterioles must be normally elastic. The

nervous inhibitory control through the vagi must also be normal, and

there must be no abnormal reflexes of any part of the body to

interfere with the normal vagus control of the heart.

While the heart beats from an inherent musculonervous mechanism,

nervous interference easily upsets its normal regularity. It may be

seriously slowed by nervous shock, fear or sudden peripheral

contractions, spasm of muscles, or convulsive contractions, or it

may be stimulated to greater rapidity by nervous excitement. It may

be slowed or made rapid by reflex irritations, and it may be

seriously interfered with by cerebral lesions; pressure on the vagus

centers in the medulla oblongata will make it very slow. Various

kinds of poisons circulating in the blood, both depressants and

excitants, may affect the rapidity or the regularity of the heart.

Therefore, if it is decided that a given heart is abnormally slow or

abnormally rapid or is decidedly irregular or intermittent, the

various causes for such interference with its normal activity must

be investigated and admitted or excluded as causative factors.

Many investigations of the rhythm of children's pulses have been

made, and some of the later investigations seem to show that not

more than 40 percent are regular, the remaining 60 percent varying

from mild irregularity to extreme irregularity.

Scientifically to determine the exact character of a pulse which is

discovered by the finger on the radial artery and the stethoscope on

the heart to be irregular, tracings of one or more arteries, veins

and the heart should be taken. Two synchronous tracings are more

accurate than one, and three of more value than two in interpreting

the exact activity and regularity of the heart.