DISTURBANCES OF THE HEART

O >> OLIVER T. OSBORNE, A.M., M.D. >> DISTURBANCES OF THE HEART

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A rising blood pressure in pregnancy, when associated with other
toxic symptoms, is indicative of danger, and Evans believes that a
systolic pressure of 160 mm, is ordinarily the danger limit.

Newell [Footnote: Newell, h. S.: The Blood Pressure During
Pregnancy, THE JOURNAL A. M. A., Jan. 30, 1915, p. 393.] has studied
the blood pressure during normal pregnancy, and finds that when the
systolic pressure is persistently below 100, the patient is far
below par, and that the condition should be improved in order for
her to withstand the strain of parturition. When the systolic
pressure is above 130, the patient should be carefully watched, and
he thinks that 150 is the danger line. Some pregnant women have an
increasing rise in blood pressure throughout the pregnancy, without
albuminuria. In other cases this rise is followed by the appearance
of albumin in the urine. Thirty-nine of the patients studied by
Newell had albumin in the urine without increase in blood pressure;
hence he believes that a slight amount of albumin may not be
accompanied by other symptoms. Five patients had a blood pressure of
140 or over throughout their pregnancy, and in only one of these
patients was albumin found. All passed through labor normally,
showing that a blood pressure below 150 may not necessarily be
indicative of a serious condition; but a patient who has a systolic
pressure over 135 must certainly be carefully watched. A fact
brought out by Newell's investigations is very important, namely,
that a continuously increased blood pressure is not as indicative of
trouble as when a blood pressure has been low and later suddenly
rises.

Hirst [Footnote: Hirst: Pennsylvania Med. Jour., May, 1915, p. 615.]
also urges that a high blood pressure in pregnancy does not
necessarily represent a toxemia, and also that a serious toxemia can
occur with a blood pressure of 130 or lower, although such instances
are rare. Hirst believes that when a toxemia is in evidence in
pregnancy while the blood pressure is low, the cause of the toxemia
is liver disturbance rather than kidney disturbance, and he thinks
this form of toxemia is more serious and has a higher mortality than
the nephritic type. Therefore in a patient with eclamptic symptoms
and a low blood pressure, the prognosis is more unfavorable than
when the blood pressure is high. He believes that if high blood
pressure occurs early in the months of pregnancy, there is
preexisting, although perhaps latent, nephritis. In these conditions
the diastolic pressure is also likely to be high.

With the patient eclamptic and stupid, whatever the date of the
pregnancy, Hirst would do venesection immediately in amount from 16
to 24 ounces, depending on what amount seems advisable. If
venesection is done before actual convulsions have occurred, the
blood pressure falls temporarily but rapidly rises again. He finds
that if a patient is past the eighth month, rupture of the membranes
will usually bring a rapid fall of from 50 to 90 points in systolic
pressure. Usually, of course, such rupture of the membranes will
induce labor. He finds that the fluidextract of veratrum viride is
valuable when eclampsia is in evidence or imminent. He gives it
hypodermically, 15 minims at the first dose and 5 minims
subsequently, until the systolic pressure is reduced to 140 or less.
He admits that this is rather strenuous treatment. He does not speak
of treatment by thyroid extracts, which has been regarded as
valuable by some other workers.

In these patients who show eclamptic symptoms, he maintains a milk
diet, and purging and sweating. It should be remembered that
venesection or profuse bleeding during induced parturition is more
valuable than sweating in all eclamptic cases and in all nephritic
convulsions. Profuse sweating does little more than take the water
out of the blood, and even concentrates the poisons in the blood.

Hirst causes purging by 2 ounces of castor oil and a few minims of
croton oil. He also advises large doses of magnesium sulphate. In
such serious disturbances as eclampsia, it is not necessary to give
a magnesium salt, which, it has been shown, can have unpleasant
action on the nervous system. Sodium sulphate is as valuable and is
not open to this danger.

Hirst urges that whatever the blood pressure, with albuminuria, as
soon as persistent headache occurs, and especially if there are
disturbances of vision, the pregnancy must be terminated at once. On
this there can be no other opinion. Temporizing with such a case is
inexcusable.

After labor has been induced there is an immediate fall of blood
pressure, which lasts some hours. The pressure will again rise, and
usually is the last sign of toxemia to disappear, and he finds that
this increased pressure may last from two to three weeks when there
is not much nephritis, and several months when there is nephritis.

Although he says he has found no bad action from ergot, either by
the mouth or hypodermically in these eclamptic cases, it would seem
inadvisable to use ergot, which may raise the blood pressure. He
finds that pituitary extract "can cause dangerous rise of blood
pressure."

Pelissier [Footnote: Pelissier: Archiv. mens., d'obst. et de gynec.,
Paris, 1915, iv, No. 5.] believes that when there is prolonged
vomiting in early pregnancy, with an increase in systolic blood
pressure, and with an increased viscosity of the blood, the outlook
is serious, and active treatment should be inaugurated.

Irving [Footnote: Irving, F. C.: The Systolic Blood Pressure in
Pregnancy, THE JOURNAL A. M. A., March 25, 1916, p. 935.] reports,
after a study of 5,000 pregnant women, that in 80 percent the
systolic blood pressure varied from 100 to 130; in 9 percent it was
below 100, at least at times, but a pressure below 90 does not mean
that the woman will suffer shock; in 11 percent the pressure was
above 130, and high pressure in young pregnant women more frequently
indicates toxemia than when it occurs in older women; high pressure
is more indicative of toxemia than is albuminuria; a progressively
increasing blood pressure is of bad omen, and most cases of
eclampsia occur with a pressure of 160 or more, but eclampsia may
occur with a moderate blood pressure. Irving believes that with
proper preliminary preventive treatment most eclampsia is
preventable.

ALTITUDE

It has long been known that altitude increases the heart rate and
tends to lower the systolic and diastolic blood pressures; that
these conditions, though actively present at first, gradually return
to normal, and that after a prolonged stay at the altitude may
become nearly normal for the individual. Burker [Footnote: Burker,
K.; Jooss, E.; Moll, E., and Neumann, E.: Ztschr. f. Biol., 1913,
lxi, 379. The Influence of Altitude on the Blood, editorial, THE
JOURNAL A. M. A., Nov. 1, 1913, p. 1634.] showed that altitude
increases the red blood cells from 4 to 11.5 percent, and the
hemoglobin from 7 to 10 percent The greatest increase in these
readings is in the first few days. It has also been shown that with
every 100 mm. of fall of atmospheric pressure there is an increased
hemoglobin percentage of 10 percent over that at the sea level.
[Footnote: Blood and Respiration at Moderate Altitudes, editorial,
THE JOURNAL A. M. A., Feb. 20, 1915, p. 670.]

Schneider and Havens [Footnote: Schneider and Havens: Am. Jour.
Physiol., March, 1915.] find that in low altitudes abdominal massage
increases the red corpuscles, and the percentage of hemoglobin in
the peripheral vessels. While there is thus apparently a reserve of
red corpuscles while the individual is in a low altitude, in a high
altitude they find such reserve to be absent; in other words,
abdominal massage did not cause this increase in red corpuscles in
the peripheral vessels. This absence of reserve is easily accounted
for by the fact that after one reaches the high altitude there is an
increase in red corpuscles and hemoblogin in the peripheral blood.

Schneider and Hedblom [Footnote: Schneider and Hedblom: Am. Jour.,
Physiol., November, 1908.] showed that the fall in systolic pressure
at altitudes is greater and more certain than the fall in diastolic,
some individuals even having a rise in diastolic pressure. This rise
in diastolic pressure is probably caused by dyspnea.

Schrumpf, [Footnote: Schrumpf: Deutsch. Arch. f. klin. Med., 1914,
cxiii, 466] on the other hand, finds that normal blood pressure is
not much affected by an ascent of about 6,500 feet, while patients
with arteriosclerosis and hypertension, without kidney disease, have
a fall in pressure. A patient with coronary disease should certainly
not go to any great altitude, while patients with compensated
valvular lesions, he found, were not injured by ordinary heights. He
found that altitude seemed to decrease high systolic and diastolic
pressures, while it even elevated those which were below normal, and
caused these patients to feel better.

Any person who has a circulatory disturbance, and who must or does
go to a higher altitude, should rest for a series of days, until his
blood pressure and blood have reached an equilibrium.

Smith [Footnote: Smith, F. C.: The Effect of Altitude on Blood
Pressure, THE JOURNAL A. M. A., May 29, 1915, p. 1812.] made a
series of observations on blood pressures at Fort Stanton which has
an altitude of 6,230 feet. He took the blood pressure readings in
fifty-four young adults, seventeen of whom were women, and found
that the average systolic reading in the men was 129 mm., and in the
women 121, while the average diastolic in the men was 84, and in the
women 82. Therefore he agrees with Schrumpf that the effect of
altitude on normal blood pressure has been overestimated. In
tuberculosis he found that the effect of altitude was not great. He
does not believe that this amount of altitude, namely, a little more
than 6,000 feet, makes much difference in an ordinary tuberculous
patient. He did not find that artificial pneumothorax made any
important change in the blood pressure. His findings do not quite
agree with Peters and Bullock, [Footnote: Peters, L. S.r and
Bullock, E. S.: Blood Pressure Studies in Tuberculosis at a High
Altitude, Arch. Int. Med., October, 1913, p. 456.] who studied 600
cases of tuberculosis at an altitude of 6,000 feet, and found the
blood pressure was increased, both in normal and in consumptive
individuals. They also found that the increase in blood pressure,
which kept gradually rising up to a certain limit, was indicative
that the tuberculous patient was not much toxic; therefore the
increase in blood pressure was of good prognosis.

CONDITIONS CAUSING CHANGE IN BLOOD PRESSURE

Woolley [Footnote: Woolley, P. G.: Factors Governing Vascular
Dilatation and Slowing of the Blood Stream in Inflammation, THE
JOURNAL A. M. A., Dec. 26, 1914, p. 2279.] quotes Starling as
finding that the blood vessels dilate from physical and chemical
changes in the musculature, and that this dilatation is caused by
deficient oxidation and accumulation of the products of metabolism,
including carbon dioxid. This dilatation ordinarily is transient and
not associated with exudation, but in inflammation the dilatation is
persistent and there is exudation. The carbon dioxid increase during
exercise stimulates a greater circulation of oxygen in the tissues
which later counteracts the normal increase in acid products. In
inflammatory processes, however, the acid accumulates too rapidly to
allow of saturation. In this case the circulation becomes slowed and
the cells become affected.

Besides these charges in the blood vessels of the muscles, the
general blood pressure becomes raised on exercise, the heart more
rapid and the temperature somewhat elevated, and the breathing is
increased. This increased heart rate does not stop immediately on
cessation of the exercise, but persists for a longer or shorter
time. The better trained the individual, the sooner the speed of the
heart becomes normal.

Benedict and Cathcart [Footnote: Benedict and Cathcart: Pub. 77,
Carnegie Institute of Washington.] have found that the increased
absorption of oxygen, showing increased metabolism, persists after
exercise as long as the heart action is increased.

Newburgh and Lawrence [Footnote: Newburgh, L. H., and Lawrence C.
H.: The Effect of Heat on Blood Pressure, Arch. Int. Med., February,
1914, p. 287.] have found that increased temperature in animals,
equal to that occurring in persons suffering with infection, reduces
the blood pressure, causing a hypotension. This shows that high
temperature alone in an individual sooner or later causes
hypotension.

Although prolonged pain may cause a fall of blood pressure from
shock, the first acute pain may cause a rise in blood pressure, and
Curschmann [Footnote: Curschmann: Munchen. med. Wehnschr., Oct. 15,
1907.] found that the blood pressure was high in the gastro-
intestinal crises of tabes and in colic, and that the application of
faradic electricity to the thigh could raise the blood pressure from
8 to 10 mm. in normal individuals.

The positive effect of decomposition products in the intestine, more
especially such as come from meat proteins, is well recognized; but
the importance, in high pressure cases, of the absorption of toxins
derived from imperfectly digested food remaining in the bowels over
night is not sufficiently recognized. Patients with high blood
pressure should not eat a heavy evening meal, and especially should
they not eat meat. Willson [Footnote: Willson, R. N.: The
Decomposition Food Products as Cardiovascular Products, THE JOURNAL
A. M. A., Sept. 25, 1915, p. 1077.] well describes the condition
caused by the absorption of these toxins. If the heart muscle is
intact, he finds such absorption in high pressure cases will show
diastolic as well as systolic increase:

The vessels pulsate and throb; the skin is pale; the head aches;
the tongue is coated; the breath is foul; vertigo is often
distressing; and not infrequently the hands and feet feel distended
and swollen. A thorough house-cleaning of the gastro-intestinal
canal causes the expulsion of the offending substances and the
expulsion of gas, whereupon the blood pressure often resumes its
normal level and the symptoms disappear.

Wilson suggests that not only the meat proteins, but also the
oxyphenylethylamin in overripe cheese may often cause this
poisoning; and cheese is frequently eaten by these people at
bedtime. Of course if any particular fruit or article of food causes
intestinal upset in a given individual, they should be avoided.

When the heart is hypertrophied in disease, the cavities of the
ventricles are probably also generally enlarged, and therefore they
propel more blood at each contraction than in normal persons and
thus increase the blood pressure.

The blood pressure is raised not only by intestinal toxemia and
uremia, but also by lead poisoning and the conditions generally
present in gout.

It has been pointed out by Daland [Footnote: Daland: Pennsylvania
Med. Jour., July, 1913.] that nervous exhaustion may raise the blood
pressure in those who are neurotic, and he finds that this
hypertension may exist for months in some cases. On the other hand,
in neurasthenics the blood pressure is generally lowered. As he
points out, there is often a very great increase in the systolic
blood pressure at the menopause, while the diastolic pressure may
not be high. This makes a very large pressure pulse. This suggests
the possibility of disturbances of the glands of internal secretion.
This hypertension is generally improved under proper treatment.

Schwarzmann [Footnote: Schwarzmann: Zentralbl. f. inn. Med., Aug. 1,
1914.] studied the blood pressure in eighty cases of acute
infection, and found that a high diastolic blood pressure during
such illness indicates a tendency to paralysis of the abdominal
vessels, and hence a sluggish circulation in the vessels of the
abdomen. He found that in seriously ill patients this high diastolic
pressure is of bad prognosis. He also found that a lower systolic
pressure with a lower diastolic pressure is not a sign that the
heart is weakening, but only that the visceral tone is growing less.
On the other hand, when the diastolic pressure rises while the
systolic falls, this is a sign of failing heart.

Newburgh and Minot [Footnote: Newburgh, L. H. and Minot, G. II: The
Blood Pressure in Pneumonia, Arch. Int. Med., July, 1914, p. 48.]
find that the blood pressure course in pneumonia does not suggest
that there is a failure of the vasomotor center. They found that
"low systolic pressures are not invariably of evil omen." They also
found that the systolic pressure in fatal cases is often higher than
in those in which the patients recovered, and they found that the
rate of the pulse is more important in determining the treatment
than the blood pressure measurements.

The work which has been described under this section is of interest
as indicating the newer experimental work on the physiology of blood
pressure. Much of it is new, however, and it is difficult to draw
absolute therapeutic conclusions from the evidence offered.

THE EFFECT OF DRUGS ON BLOOD PRESSURE

Free catharsis is a well established and valuable method of
relieving the heart in many cases of broken compensation, and in
cases with high blood pressure even while compensation is still
good, salines administered once or twice a week assist in
elimination, and in the reduction of blood pressure.

However, profuse purging in heart disease may be followed by
unfavorable symptoms, especially when the systolic blood pressure is
low. When there is hypotension, or when the diastolic pressure is
high and the venous pressure is high, and when there is edema or
effusion, watery catharsis should be caused only after due
consideration, and always with a careful watching of the effect on
the heart and blood pressure. The blood pressure is lowered by such
catharsis, and the heart is often slowed. Neilson and Hyland
[Footnote: Neilson, C. H., and Hyland, R. F.: The Effect of Strong
Purging on Blood Pressure and the Heart, THE JOURNAL A. M. A., Feb.
8, 1913, p. 436.] studied the effect of purging on the heart and
blood pressure, and were inclined to the view that in serious heart
conditions brisk purging should not be done. They think that the
slowing of the heart after such purging may be, due to an increased
viscosity of the blood, or perhaps to a reflex irritation from the
purgative on the intestinal canal.

Pilcher and Sollmann [Footnote: Pilcher and Sollmann: Jour.
Pharmacol. and Exper. Therap., 1913, vi, 323.] have shown that the
fall of blood pressure after the administration of nitrites is
mostly due to the action of these drugs on the peripheral vessels.
Chloroform, of course, depressed the vasomotor center, but ether had
no effect on this center, or slightly stimulated it. Such
stimulation, however, Pilcher and Sollmann believe may be secondary
to asphyxia. Nicotin they found to cause intense stimulation of the
vasomotor center. Ergot and hydrastis and its alkaloids seem to have
no effect on the vasomotor center. Strophanthus acted on this center
only moderately, and digitalis very slightly, if at all. Camphor in
doses large enough to cause convulsions stimulated the vasomotor
center. In smaller doses it generally stimulated the center
moderately, but not always. Even when this center was stimulated,
however, the camphor did not necessarily increase the blood
pressure. The rise in blood pressure from epinephrin is due entirely
to its action on the peripheral blood vessels and the heart. It has
no action on the vasomotor center. They found that strychnin in
large doses may stimulate the vasomotor center moderately, but
usually it did not act on this center unless the patient was
asphyxiated; then it acted intensely. The conclusion to be drawn
from their experiments is that when there is asphyxia, increased
venous pressure, and also a rising blood pressure from the
stimulation of carbon dioxid, strychnin is contraindicated.

It should be recognized that digitalis very frequently not only does
not raise blood pressure, but also may lower it; especially in
aortic insufficiency and when there is cyanosis. Even with some
forms of angina pectoris, digitalis in small doses may reduce the
frequency of the pain. This decrease of pain following the use of
digitalis has in some cases been ascribed to the improvement of
coronary circulation and resulting better nutrition of heart muscle.
Of course under these conditions the action of digitalis must be
carefully watched, and it should not be given too long.

Although sodium nitrite and nitroglycerin have but a short period of
action, in laboratory experimentation, in lowering the blood
pressure, when given repeatedly four or five times a day the blood
pressure is lowered in very many instances by these drugs. Sometimes
when the blood pressure is not lowered, there is relief of tension
in the head from high pressure, and the patient feels better. There
is also relief of the heart when it is laboring to overcome a high
resistance. One drop of the official spirit of nitroglycerin on the
tongue will cause a lowering in the peripheral pressure pulse, the
radial pulse becoming larger and fuller. This effect begins in three
minutes or less, reaches its maximum in about five minutes, and the
effect passes off in fifteen minutes or more. [Footnote: Hewlett, A.
W., and Zwaluwenburg, J. G. Van: The Pulse Flow in the Brachial
Artery, Arch. Int. Med., July, 1913, p. 1.]

It has been stated that iodids are of no value except in syphilitic
arteriosclerosis, but iodids in small doses are stimulant to the
thyroid gland, and the thyroid secretes a vasodilating substance.
Therefore, the use of either iodids or thyroid would seem to be
justified in many instances of high blood pressure.

Fairlee [Footnote: Fairlee: Lancet, London, Feb. 28, 1914.] has
studied the effect of chloroform and ether on blood pressure, and
finds that there is a fall of pressure throughout the administration
of chloroform, and but little alteration of the blood pressure
during the administration of ether. It may cause a slight rise, or
it may cause a slight fall, but changes in pressure with ether are
not marked. When there is slight surgical shock present, as from
some injury, they found that chloroform would lower the pressure
considerably. Hence it would seem that chloroform should not be used
as an anesthetic after serious injuries.

THE EFFECT OF DRUGS ON VENOUS BLOOD PRESSURE

Capps and Matthews [Footnote: Capps, J. A., and Matthews, S. A.:
Venous Blood Pressure as influenced by the Drugs Employed in
Cardiovascular Therapy, THE JOURNAL A. M. A., Aug. 9, 1913, p. 388.]
have shown that even with first class preparations of digitalis,
there may be only a moderate gradual rise in arterial pressure, but
not much change in venous pressure. Venous pressure was not much
affected by small doses of epinephrin, but with large doses it rose
from 10 to 80 mm. Pituitary extract acts somewhat similarly to
epinephrin. Caffein, though raising the arterial pressure, did not
influence the venous pressure. Strychnin did not raise either
pressure until the dose was sufficient to cause muscular
contractions. They found that the nitrites caused a fall in venous
pressure as well as arterial pressure, although the heart might be
accelerated and more regular. They think that the nitrites act by
depressing the nerve endings in the veins as well as the arteries.
Morphin they found did not act on the venous pressure, although it
lowered arterial tension, in ordinary doses of 1/8 or 1/6 grain; but
with doses of from 1/4 to 1/2 grain, both arterial and venous
pressures were lowered. They found that alcohol in ordinary doses
did not influence the venous pressure, although it lowered the
arterial pressure; but very large doses lowered the arterial and
raised the venous pressure. They think that when the venous pressure
is increased only by large doses of epinephrin, pituitary extract
and alcohol, the effect is due to failure of the heart, although it
may be due to an increase of carbon dioxid in the blood, in other
words, to asphyxia.

HYPERTENSION

Arterial hypertension may be divided into stages. In the first stage
the arteries are healthy, but the tone, owing to contraction of the
muscular walls, is too great. This condition or stage has been
termed "chronic arterial hypertension." This condition may be due to
irritants circulating in the blood, to nervous tension, to incipient
chronic interstitial nephritis, or may be the first stage of
sclerosis of the arteries. If from any cause this hypertension
persists, the muscular coats of the arteries will become more or
less hypertrophied, and sooner or later degenerative changes begin
in the intima, and finally fibrosis occurs in the external coat of
the arteries; in other words, arteriosclerosis is in evidence. If
the patient lives with this arteriosclerosis, a later stage of the
arterial disease may occur which has been termed atheroma, with
thickening, and possibly calcareous deposits in some parts of the
walls of the vessels, while in other parts the coats become thinner
and insufficient. At this stage the heart, which has already shown
some trouble, becomes unable to force the blood properly against
this enormous resistance of inelastic vessels and the blood pressure
begins to fail as the left ventricle weakens.

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