Definition.—Cardiac dilatation is an increase in the size of the cavities of the heart, which may be primary, with attenuation or thinning of its walls; or secondary, with thickening of its walls, hypertrophy, and dilatation.
Etiology.—Acute primary dilatation may be the result of undue exertion, without proper training, as excessive bicycling, mountain climbing, overwork on the running track, horizontal bar, or rowing, as witnessed in the enthusiasm of new members of athletic associations.
Heavy lifting by workmen who overtax their strength; strong emotional excitement, as intense anger or extraordinary fright, may also give rise to this form; in fact, any condition that gives rise to increased intra-cardiac pressure may produce dilatation. The right ventricle, in these cases, suffers most.
Dilatation from chronic valvular lesions have already, been considered, and are among the most frequent causes; here, however, there is always hypertrophy as well. Obstruction of the pulmonary vessels due to chronic bronchitis, emphysema, tuberculosis, and kindred diseases, will also give rise to dilatation of the right heart.
Any disease that weakens the heart is a possible cause; thus myocarditis, resulting from the infectious fevers, such as typhoid fever, scarlet fever, and diphtheria; also rheumatic endocarditis and pericarditis; in fact, any condition that impairs the nutrition of the heart is a possible factor in producing dilatation.
Pathology.—The left auricle and right ventricle are the cavities most frequently affected, though any one or all combined may be involved in the process. When dilatation and hypertrophy are combined, it is usually secondary and due to valve lesions. If there be aortic insufficiency or stenosis, the left ventricle is first involved, to be followed in turn by the left auricle, right ventricle, and right auricle. Mitral insufficiency or stenosis is followed by dilatation of the left auricle, to be followed in turn by dilatation of the right ventricle and right auricle. Where chronic pulmonary diseases exist, the right heart will be the part affected.
The degree of dilatation varies: in extreme cases the auricles have been known to contain twenty or more ounces. If the ventricles are the cavities involved, the heart is broadened: but if all the cavities share in the dilatation, the organ assumes a globular form. Where there is extreme dilatation the venae cavae and pulmonary veins also share in the same progressive changes. Parenchymatous, fibroid, or fatty degenerations of the heart and endocardium take place with the progressive changes.
Other organs are impressed in the same manner. The liver becomes engorged, and then undergoes degeneration, jaundice being an accompanying factor. The mucous membrane of stomach and bowels becomes congested, giving rise to severe functional disturbance. The brain early feels the effect of the general venous congestion, as seen by engorgement of the pia mater and increase of fluid in the ventricles.
Symptoms.—Dilatation being associated with those of hypertrophy, valvular lesions, and other cardiac complications, naturally shares the symptoms of the various combinations, feebleness, and incompleteness being the most pronounced. In proportion to the amount of dilatation do we recognize the heart's waning powder. The patient experiences an undefined, uneasy sensation in the cardiac region; not exactly a pain, yet oppression of a distressing character. Dyspnea is one of the prominent symptoms, increasing as the cavities enlarge.
Where the right heart is involved, pulmonary symptoms soon develop, a hacking cough, attended with a serous and sometimes sanguineous expectoration, follows. As the dyspnea increases, the patient is unable to lie down without bringing on a series of spasmodic coughs, commonly known as cardiac asthma.
The pulse, as well as the apex-beat, is feeble. The pulse is often irregular both as to power and rhythm. The extremities, and even the body, are apt to be cool. Any undue exertion, either mental or physical, aggravates all the symptoms, especially the dyspnea.
The veins, particularly those of the neck, are distended, and the patient is more or less livid or bluish in appearance. Owing to congestion of the liver, there is a sense of weight and oppression in the right hypochondrium, and the patient takes on an icteric hue.
There is more or less gastric disturbance, resulting from the general congestion, and attacks of vomiting are not infrequent, digestion is imperfect, and the evidence of impaired nutrition is apparent. Diarrhea announces the congested condition of the intestinal tract, and adds to the debility.
The kidneys are also frequently involved, and nephritis is a common attendant, the urine being scanty, high-colored, albuminous, and contains casts.
Cerebral congestion is attended by headache, dizziness, and sometimes vertigo. Delirium rarely occurs. With general venous congestion, edema appears, first in the feet, gradually encroaching upon the body, till finally anasarca or general dropsy results.
Physical Signs.—Inspection.—If the patient be thin or emaciated, and the dilatation be of the left ventricle, the apex-beat will be seen to be displaced downward and to the left. If the dilatation be of the right ventricle, the pulsation will be seen in the epigastrium. If the patient be well nourished, the feeble apex-beat may not be seen, and other signs must be looked for to aid in the diagnosis. In advanced cases, visible pulsation of the jugulars is pronounced.
Palpation.—The feeble, undulating apex-beat may be felt, though not constantly. If the dilatation be of the right heart, a pulsation may be quite pronounced over the liver. The jugular pulse may be readily felt, even though not visible.
Percussion.—Dullness will be increased transversely to the left axillary line in dilatation of the left ventricle, and to the right nipple line when the right heart is dilated. If the auricles are involved, the area of dullness may extend to the first rib and transversely as far as when the ventricles are involved.
Auscultation.—Dilatation is always associated, more or less, with valvular insufficiency or stenosis, and, therefore, pre-existing murmurs will necessarily influence the sound made by dilatation. The first and second sounds are quite similar, and are short and sharp, resembling fetal heart-sounds, the long pause being shortened. Irregular pulsations, both as to time and force, have been noted, and the canter rhythm is not uncommon.
Diagnosis.—The diagnosis of dilatation of the heart is less difficult than many other organic lesions. The wavy or undulating apex-beat, the first and second sounds being sharp and of the same length; the canter rhythm, or embryocardia; the frequent irregular pulse; pulsation in the epigastric region; the wavy pulsation in the jugulars, and the general cyanotic appearance, together with anasarca, make a group of diagnostic symptoms that can scarcely lead to a mistake.
Prognosis.—The prognosis of cardiac dilatation is always unfavorable, and though life may be prolonged by careful living, change of climate, and remedies that add tone to the organ, we are not to forget that the changes are progressive and the termination is death in most cases.
Treatment.—The patient must clearly understand that severe muscular or mental exertion, or anything that causes unusual excitement, must be positively forbidden. The patient should lead a quiet life, as much in the open air as possible, and have such diversion as will attract his attention away from himself.
The aim of all treatment in cardiac dilatation is to increase the muscular power of the heart. To make good muscle requires good blood, and this requires good digestion. Diet, then, will be an important factor in the treatment; this should consist of good, nutritious food, easily digested, and only enough fluids allowed as is compatible with health.
Any disturbance of the stomach should be corrected, constipation should be overcome, and hepatic derangements should be controlled. A few remedies will be indicated, and should be given to overcome special conditions. For the small, feeble, irregular pulse, aconite, in the small dose, will give good results. We give the remedy, not for its sedative effect, but to add tone to the heart. Five drops of the agent to four ounces of water, and a teaspoonful every three hours, will not disappoint you.
Cactus.—This remedy does not overstimulate and thus weaken the heart action, but its tendency is to increase the heart's nutrition and add power to the muscle. Of the specific tincture, use twenty drops, to water four ounces. Goss says of this remedy: "If the patient suffers from a cramping pain, like a band around the heart, I have always found this agent gives quick relief."
Crataegus.—This is a remedy that is receiving a great deal of attention in cardiac lesions, and as a tonic and restorative has given excellent results. The remedy should be given in from five to ten drop doses.
Lobelia.—This will afford some relief to the distressing dyspnea, though we are not to forget the mechanical obstruction causing the difficult breathing and expect too much of the remedy.
Apocynum is the remedy when dropsical effusion appears. It not only stimulates the kidneys to carry off accumulations, but strengthens the heart at the same time.
Digitalis will be used for similar conditions.
Lycopus Virginicus will be a good remedy where pulmonary troubles arise, attended by cough and hemoptysis.
Spigelia, alternated with bryonia, will afford relief when there is pain, sharp and stabbing in character.
No matter what agents are employed, the patient should be kept as quiet as possible, saving the heart any unnecessary work. Smoking should be prohibited.