the first two, however, in what is normally the period of silence immediately preceding the first sound-hence presystolic.

Mitral regurgitant murmurs are heard best at the apex of the heart; they are transmitted in the course of the fifth and sixth ribs to the axilla, and may be heard below the posterior inferior angle of the scapula. Mitral obstructive murmurs are best heard at the apex of the heart, or a little above the apex; they are but feebly transmitted. Aortic regurgitant and aortic obstructive murmurs are most distinctly heard at the junction of the second costal cartilage on the right with the sternum; the former are transmitted downwards in the course of the sternum, the latter upwards in the course of the great vessels, especially the carotid. Murmurs generated at the orifices and by the valves of the right side of the heart are exceedingly rare. Tricuspid regurgitant and obstructive murmurs are best heard at the ensiform cartilage, or a little farther to the right. Pulmonary murmurs should be best heard in the second intercostal space on the left, close to the margin of the sternum. In anemia, soft blowing murmurs, dependent upon the condition of the blood, are

heard in the same situation.

All murmurs heard in the precordial region are not endocardial. Auscultation reveals as well the sounds of pericardial friction as of adjacent pleural friction.

How are murmurs due to organic disease to be distinguished from so-called functional murmurs?

In addition to adventitious sounds generated at the orifices of the heart as a result of structural changes, murmurs are heard when the condition of the blood is deteriorated, or when, from disturbed action of the heart or other cause, abnormal currents are generated in the blood-stream. These so-called functional murmurs are distinguished by their inconstancy and their softness; they are usually heard only at the base of the heart and over the body of the organ; they are not transmitted; they are intensified by pressure with the stethoscope; and they disappear with the removal of the conditions upon which they depend. Organic murmurs are usually harsher, more constant, and vary comparatively little in character and intensity.

What is the sphygmograph?

The sphygmograph is an instrument by which an artery is made to record certain of the characters of its pulsation. The sphygmogram (Fig. 20) is an important aid in diagnosis, but

cannot be relied upon apart from the ordinary rational and physical signs. The use of the sphygmograph and the significance of its tracings must be learned by experience.

Malformation.

What are the most common malformations of the heart? The most common malformations of the heart consist in an imperforate interventricular septum and a failure of the foramen ovale to close.

To what symptoms do malformations of the heart give rise?

Individuals in whom there exist serious abnormal communications between the lateral halves of the heart rarely reach adult life. Cyanosis is the most common symptom. Systolic murmurs are heard practically indistinguishable from those occasioned by valvular derangement.

What is dextrocardia?

Dextrocardia.

Dextrocardia is a congenital displacement of the heart on the right side, commonly associated with displacement of the liver on the left and of the spleen on the right.

How is dextrocardia to be recognized?

In case of dextrocardia the impulse of the heart is wanting in its usual situation, and is seen to the right of the sternum. The area of cardiac percussion-dulness occupies on the right an extent corresponding to that which it normally occupies on the left. The sounds of the heart are heard on the right side instead of on the left. The hepatic percussion-dulness is not found in its usual situation, but in a corresponding position on the left. The splenic dulness is found on the right instead of on the left.

Functional Disturbance of the Heart.

What is meant by functional disturbance of the heart? Under various conditions, as when the nutrition is impaired or the digestion is deranged, as a result of overwork, or of dissipation, or of the excessive use of tobacco, or tea, or coffee, and in connection with gout or lithemia, with hysteria or hypochondriasis, the action of the heart may be deranged without recognizable structural change. There will be present such symptoms as pain, palpitation, anxiety, headache, vertigo and breathlessness, sometimes with irregularity and increased frequency of the heart's action. The diagnosis depends upon the recognition of the primary condition and upon the absence of the physical signs of a cardiac lesion. Functional disorder, great in degree and long continued, may lead to structural change.

What is tachycardia?

Tachycardia.

Tachycardia is a term applied to a somewhat rare condition of excessive rapidity of the action of the heart, accompanied with palpitation, the rhythm of the heart sometimes remaining unaffected. The pulse may exceed 200 beats a minute. Occurring in paroxysms, the qualification paroxysmal is applied. When no etiologic lesion is discoverable, the condition is termed essential paroxysmal tachycardia. The paroxysm usually begins suddenly,

with or without warning; at times without apparent exciting cause; at other times seeming to result from some such condition as overdistention of the stomach. Tachycardia may be due to temporary paralysis of the vagus or stimulation of the cardiac accelerator nerve. Increased cardiac dulness and indefinite murmurs may be observed during the attack, and disappear with subsidence of the symptoms. The condition may be unattended with other symptoms, and ordinarily does not shorten life. It may be a part of other neuroses. It has been observed

in women at the menopause.

How does tachycardia differ from angina pectoris ?

Tachycardia is wanting in the threatening symptoms of angina pectoris-the anxiety, the pain, the cardiac failure. Rapidity of the heart's action and palpitation are the essential features of tachycardia; while in angina pectoris the pulse is of variable frequency.

How does tachycardia differ from exophthalmic goiter?

Palpitation of the heart and increased frequency of the pulse are among the earliest phenomena of exophthalmic goiter. Before the thyroid gland has become enlarged or the eyeballs protrude, the distinction from tachycardia is not possible. There is no difficulty in the diagnosis, however, when not only the exophthalmos and the goiter, but the array of other symptoms that characterize exophthalmic goiter, have also developed.

Irritable Heart.

What are the phenomena of irritable heart?

Irritable heart is a condition originally observed in soldiers in active service, in which there are in addition to increased frequency of the action of the heart, often with disturbed rhythm, recurring attacks of palpitation and pain in the precordia. There are usually headache and vertigo, especially during the paroxysms. The general health may suffer little or not at all. The first sound may be short and sharp or may be barely audible; the second sound is accentuated. There is no constant murmur. The pulse is compressible and easily influenced by

position. Respiration is but little if at all accelerated. A similar condition may develop in civil life in those unaccustomed to arduous labor called upon to perform unusual tasks. It has also been found in athletes and others who have committed excesses in physical exertion, and in masturbators. Under proper regimen, restoration to the normal results; under other circumstances, hypertrophy of the heart develops.

How does irritable heart differ from tachycardia?

Irritable heart results from well-recognized causes that are not concerned in tachycardia. In irritable heart the frequency is less than in tachycardia, and is habitual; in tachycardia the increased frequency is extraordinary and usually occurs in paroxysms. It is pain and palpitation rather than increased frequency of action that marks the paroxysmal seizures of irritable heart. Tachycardia is also wanting in the distressing subjective sensations and the grave issue of irritable heart.

Angina Pectoris.

What are the characteristics of angina pectoris ?

Angina pectoris is a paroxysmal disorder for which no definite structural lesion has been found. Perhaps the most common condition associated with it is atheroma of the coronary arteries.

The attack sets in suddenly, with a sense of oppression, dyspnea, and pain in the precordia, rising to a high pitch of intensity, and attended with a sense of impending dissolution-and not uncommonly death does occur in the paroxysm. There is often a sensation as of throttling. The pain in the heart is described as "clutching," "squeezing," and "tearing." The pain radiates in various directions from the heart, especially to the left shoulder, and extends down the left arm. The face is pale, the features drawn, the pulse variable. The attacks may occur spontaneously, but are usually brought on by excitement or exertion, or by gastro-intestinal derangement. They recur with varying frequency, sometimes over a long period of years.