APEX BEAT-PARKER.

11

the parasternal and mammillary lines, and corresponds to the apex itself or to a point a little inward from it. (Krehl). The whole chest should be laid bare, then inspected and palpated from the sternum to the posterior axillary line, and from the third to the ninth intercostal space. Otherwise an apex beat, in an abnormal situation, is liable to be overlooked.

The position of the apex beat may have a considerable variation normally. A normal apex beat may be found in the fourth interspace closely outside the mammillary line. This occurs commonly in the female, as frequently as 12 per cent and in children under ten years of age this is the normal location. Toward the upper limits of childhood, i. e., between twelve and fifteen, it is often difficult to decide whether the apex beat is normally located or not. In the aged with the usual. accompanying arteriosclerosis and emphysema, the apex beat is found displaced downward and outward in the sixth interspace. The normal location of the apex beat on the right side in situs inversus must be borne in mind.

The apex beat may be normally absent

1. When a thick layer of lung lies between the heart's apex and the chest wall, or when the chest wall itself is very thick.

2. When the intercostal spaces are narrow, and the apex strikes a rib instead of an intercostal space.

3. When the long axis of the heart so lies that the impulse against the chest wall is wanting.

Under these conditions it is often possible to develop an apex beat by instructing the patient to lean forward, so that the heart may press away the intervening portion of lung and its apex move to a lower level. As inferred above, the apex is not stationary, but moves downward slightly by inspiration or by change from the horizontal to the erect posture, and also about a finger's breadth laterally when the patient lies first on one side and then on the other. A test of the mobility of the apex will guard against an erroneous diagnosis of dilatation in those cases with very mobile or so-called "wandering hearts" associated with a high diaphragm which may crowd the highly movable heart into contact with a large extent of chest wall, whereby an extensive area of dullness is produced.

In the diagnosis of an abnormally located apex beat a variety of other pulsations in and near the cardiac region must be differentiated and excluded.

Associated with certain conditions, such as dilatation of the heart and retraction of the lungs, which bring the heart into closer relation

with the chest wall, is observed a diffuse pulsation extending over several intercostal spaces. It may not then be possible to locate a circumscribed apex beat, but the portion of this pulsating area lying farthest downward and outward is to be regarded as the apex beat.

Among other pulsations of the chest wall near the heart, are often seen in the right or left second intercostal space, close to the sternum, undulations which are transmitted from the aorta or pulmonary arteries. These pulsations occur later than those of the apex, but the difference is usually too slight to be detected. However, a confusion of them with the apex beat will rarely arise.

A pulsation of the epigastrium and the lower end of the sternum is often seen associated with a low position of the diaphragm or an enlarged right heart. It can be distinguished from the apex beat by the location of its greatest intensity at the lower end of the sternum, or close to its left border, and by the low, when standing, position of the diaphragm.

Another pulsation met with in the epigastrium a little to the left of the median line, is transmitted from the abdominal aorta and is differentiated by coming perceptibly later than the apex beat.

The appearance of the apex beat in an abnormal position signifies an abnormal position of the heart apex, which may be brought about either by a displacement of the heart as a whole or by a displacement of the apex alone in virtue of a lengthening of the left ventricle by dilation.

However, in studying the location of the apex beat, the influence of chest deformities must be borne in mind. And it should be remembered that the apex beat of a normal heart, normally situated, may, in deformed chests, appear at an abnormal place on the surface. On the other hand, the apex of a widely dilated heart may be found within the mammary line, where, during childhood, the enlarged heart has caused the chest wall to bulge and the mammary line to move outward.

The etiological factors displacing the heart as a whole may displace the apex beat in any direction from its normal position. When the apex beat is displaced through dilatation of the ventricle, it is displaced in two directions only-downward and outward.

The significance of a displaced apex beat is seen in an enumeration of the causes of displacement.

I. Displacing the heart as a whole. 1. Congenital dextrocardia.

APEX BEAT-PARKER.

13

2. Deformities of the thorax, as the result of rachitis, spondylitis, occupation, etc.

3. Retracting pleural adhesions.

4. Encroachments of pleural exudates and tumors, pneumothorax, etc.

9. Displacement of the diaphragm upward through overdistension of the abdomen by ascites, meteorismus, dilatation of the stomach, tumors and pregnancy.

II. Causing dilatation of the left ventricle and thus a displacement of the apex beat.

1. Abnormal weakness of the heart muscle, caused by exhaustion and degeneration of the same.

2. Excessive labor in the propulsion of the blood.

h. Ingestion of large amounts of fluids-"beer heart."

i. Excessive use of tobacco.

j. Basedow's disease.

It will be seen from these enumerations that although the mere presence of the apex beat in an abnormal place gives but little suggestion as to the diagnosis of the particular etiological factor, the displacement alone has an important prognostic bearing upon the case, and should prompt the physician to a most careful and thorough examination.

Of the etiological factors in the first category, all except congenital dextrocardia and pregnancy are pathological conditions. The former may be dismissed on account of its rarity, and the latter could scarcely offer a diagnostic difficulty at a stage when the heart is encroached upon. Though the remaining factors are not of uniform prognostic significance, they are all conditions or at least strongly suggestive of conditions incompatible with a good life expectancy.

Of the second series of causes, those producing displacement

of the apex beat through dilatation of the left ventricle, some carry absolutely unfavorable prognoses, while all of them are incompatible with long life expectancies.

Of equal importance and of greater diagnostic significance than the position of the apex beat is the character of its impulse with reference to height and especially to strength. The height or altitude through which the apex beat raises the wall in the intercostal space depends on the thickness of the intervening layer of lung, the width of the space and the character of the heart's action, e. g., a quickly running systolic contraction raises the chest wall higher than slow contractions.

With the many and varied conditions giving rise to a high apex beat, no conclusions as to the condition of the heart can be drawn from it. Hence the high impulse should be distinguished from the strong or heaving impulse which does have great diagnostic signifi

cance.

A heaving apex beat is characterized by a resistance of impulse. It is not easily overcome by the finger pressed against the chest wall. The simple high impulse is soft, and offers little resistance. The height may be out of proportion to the power of the heart as seen in marked aortic insufficiency. A high apex beat may be associated with heart weakness even where there is a large degree of dilatation. (Sahli). The heaving beat, on the other hand, may be high, but it is not necessarily so, e. g., in nephritis with cardiac hypertrophy, where dilatation has not occurred, the beat is heaving but not high. The heaving beat raises an extensive area of the chest wall-the simply high, a more limited.

In examining for a heaving beat, one places the fingers perpendicularly to the pulsating area, and exerts pressure. If the finger is raised in spite of strong pressure, it is described as a heaving apex beat. By practice one acquires skill in estimating the strength of the impulse as with the radial artery. The heaving apex beat is regarded by Bamberger and Traube as a sure sign of hypertrophy of the left vertricle, and in doubtful cases as the only sure sign. The heaving apex beat, then, can be regarded as pathognomonic of an hypertrophied ventricle, for, in the hypertrophied ventricle only, does the systolic transformation occur with such force that the apex beat is abnormally resistant. Since the character of the apex beat is an indication of the ventricular power, it is evident that observation of the character of the apex beat from day to day will furnish most

APEX BEAT-PARKER.

15

important information as to the ventricular power in those lesions accompanied by hypertrophy of the left ventricle.

Constant attention to the apex beat during pericarditis also is of great assistance in detecting the occurrence of effusion, since the impulse of the apex weakens in proportion to the accumulation of fluid in the pericardial sack. When this weakening appears, and a weakening of the radial pulse in consequence of heart dilatation can be excluded, a mechanical separation of the heart from the chest wall can with reasonable certainty be diagnosed. Of course an apex, fixed by old adhesions, is not displaced by fluids.

When, during an attack of pericarditis, the apex beat has disappeared, the diagnosis of effusion is very strongly corroborated if, upon placing the patient on his right side, the beat reappears. This occurs when the fluid settles so that the apex can again come in contact with the chest wall.

Other phenomena of less significance are at times associated with the apex beat. The impulse at the apex is sometimes replaced by a retraction which has no special significance when confined to one intercostal space. When it occurs over a wider area in the lower cardiac region, however, it is a most suggestive sign of obliterative pericarditis, or, as the German writers term it, concretio cordis.

A comparison of palpation and inspection with auscultation and percussion of the cardiac region is instructive as to the relative value of these methods in the diagnosis of heart disease.

With regard to the difficulty of technique, palpation and inspection possess some advantages over auscultation and percussion. The latter two methods presuppose, for reliable results, an inherent ear for music to a greater or less degree, in order that one can be able to distinguish strength, duration, quality and pitch of sound, and also an extensive special training of the sense of hearing. Moreover, quiet surroundings are indispensable to the satisfactory practice of auscultation and percussion. On the other hand, the senses of sight and touch, employed in palpation and inspection, are not only in constant exercise from childhood to maturity but are called into service in every line of our professional work. Hence it will be seen that the physician is, on the whole, equipped for more reliable results by inspection and palpation than by auscultation and percussion. The facts, themselves, elicited by palpation and inspection compare favorably in their diagnostic significance with those obtained by percussion and auscultation.

By percussion of the cardiac region we determine the extent