THE SIGNIFICANCE OF THE APEX-BEAT IN THE. DIAGNOSIS OF CARDIAC CONDITIONS

By Arthur F. Beifeld, l'vI .D.

This paper has for its object a demonstration that the inspec­tion, and particularly the palpation, of the apex beat, are as valu­able as percussion of the heart borders and auscultation over the­precordium in the diagnosis of cardiac affairs.

The student just entering clinical work associates heart diag­nosis with his stethoscope only; development teaches him the value' of palpation over the puncta ma_-rili'w of the valves, of percussion, of observation of the veins of the neck, of the condition of the­liver, and of ankle edema. It requires a long time, however, for him to realize that the study of the position and character of the apex beat is anything more than a refinement in diagnosis.

Method of K-ramination.- The heart is best examined after the lungs have been gone over both anteriorly and posteriorly, not as a secondary part of the pulmonary examination from in front. That is to say, one should go over the anterior chest wall with the patient in the recumbent position, giving his attention to the lungs only; this done, he should place the patient in the sitting posture and complete the lung findings posteriorly. He is now in a posi­tion to make at least a preliminary pulmonary diagnosis and can turn his undivided attention to the heart with the patient again lying down.

The logic of this routine will be apparent if we consider the many relations of cardiac diagnosis to lung pathology, such as the dislocation of the heart by fluid or adhesions, or a cardiac dilatation in pneumonia, or a tuberculous apex distinct posteriorly only and rendering the diagnosis of a suspected mitral lesion doubtful. All of these pulmonary and pleural conditions may be apparent behind only; henc,e to sandwich the examination of the heart between the. two parts of the lung examination is not logical from a pathological. point of view.

We return from this digression to our patient lying squarely upon his back, the pulmonary examination having been completed. The following remarks we shall confine to conditions in the adult.. 'Vith the patient's feet toward the source of illumination in a well' lighted room, visual search is made for the apex. In the absence· of unfavorable conditions, which will be gone into later, the systolic' impulse representing the apex beat can be seen in the fifth inter­space within the mammillary line (constructed in the female). In­spection can give us the location of the beat, a fair idea of its breadth, but only a meager notion of how circumscribed it is. Pal-

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pation fills in the defects. Localizing the impulse, we mark it with an appropriate pencil. It is next palpated with the pulp of the index finger to determine its resistance, with the same idea in view as one judges the tension in the radial artery by the pressure needed ro eradicate it. Finally, the apex is grasped between the index finger and thumb, in a twofold effort; first to determine its breadth and second to find whether it is well circumscribed, or, on the other hand, whether its borders fade away gradually.

It has been assumed that the apex beat has been seen and felt in the dorsal prone position. In many instances, however, this is not possible. In this contingency, the patient should be rolled over on his left side and the same routine gone through as previously outlined. The change of position affects only the dislocation of the apex outward, not downward; the location of the apex as re­gards the mammillary line can be controlled later by percussion and the Roentgen plate, if necessary.

The normal adult apex beat is in the fifth interspace 1 cm. or more within the nipple line, about 1.5 cm. in breadth (in the female a little narrower), and easily eradicated by the palpating finger. Its borders can be clearly felt, that is, it is well circumscribed, and can be marked with pencil. It is made up almost entirely by the left ventricle.

Turning now to the diagnostic data obtainable from the exam­ination of the apex beat, we shall consider the subject under its various abnormal aspects, as follows:

Abnormal Position.-The position may be abnormal transiently or permanently. Meteorisl11us, if marked, and ascites push the apex upward and outward. Fluid in the pleural sac dislocates the apex to the right or left; it may return to the normal after paracentesis. In these two conditions, in the absence of other pathological changes, cardiac disease is not suggested because the apex is simply out of piace, not broader than normal nor more resistant.

A pure dislocation, permanent in nature, but with 11 0 other changes in the quality of the beat may be seen .in adhesive pleuritis, aneurysm of the ascending aorta ( the dislocation is often the only recognizable cardiac abnormality), tumors of the mediastinum, and in arteriosclerosis of the ascending aorta (the resulting tortuosity necessitating more space and pushing the heart downward). En­physema also tends to dislocate the apex outward, but here ·the ac­companying enlargement of the right heart plays a part, as is noted below. The so-called pure permanent dislocations must be looked at guardedly, as other changes often enter into consideration; in arteriosclerosis of the aorta, for example, a left ventricle enlarge­ment may be due to generalized arteriosclerosis or to renal lesions (but see below).

Changes in location due to cardiac disease are always evi-

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denced by other abnormal apex findin gs. i. e., increased breadth and resistance. In left ventricle enlargement, types of which are aortic insufficiency, mitral disease, and contracted kidney, the apex is found dislocated to the left in variable degree. In dilatation and hypertrophy of the right heart alone, as from emphysema, scoliosis, etc .. the apex may also be outside its normal position, but here the large right ventricle acts mechanically, pushing the entire organ to the left.

Abnorlllal Breadth.-This may be caused by dilatation and hypertrophy of either ventricle. There is no need to enter into the etiology of these conditions. By way of exception to the rule, I may be permitted to mention a case in which the dislocation, breadth, resistance and good definition of the apex led naturally to the diag­nosis of dilatation and hypertrophy of the left ventricle. At autopsy was found an anelwYS'fna cordis partiale (Rokitansky).

Definition of the Broadened Apc.1'.-i\Iore valuable than the diagnosis of the dilatation and hypertroph)" of the ventricle from the breadth of the beat is the determination of which ventricle is in­volved, or whether both are affected, from the definition of the apex beat. Dilatation and hypertrophy of the left ventricle alone gives a broad, well circumscribed apex, the inner and outer borders of which can be exactly determined. Enlargement of the right heart alone causes an abnormally broad beat not easily picked up between the fingers. That right ventricular hypertrophy does not cause as marked a broadening of the apex as does a similar and equal condi­tion of the left is explained anatomically by the fact that the muscle bundles of the left chamber are larger and thicker than of the right. Right ventricular enlargement does not produce as circumscribed an apex beat as does the left because even under pathological con­ditions the left ventricle form s most of the beat.

Dilatation and hypertrophy of both ventricles cause a wide, diffuse apex beat. At the best, the diagnosis of enlargement of the right ventricle is not always an easy one and advantage must be taken of other phenomena such as epigastric pulsation, trembling of the lower sternum, percussion, and of the Roentgen ray.

There is one condition that may well be mentioned here, the existence of which is denied by some pathologists, but examples of which are apparently occasionally seen at autopsy. This is concen­tric hypertrophy of the left ventricle, as noted in the early course of a chronic nephriti s. This condition, par excellence, can be diag­nosed by the character of the apex beat, which is in normal posi­tion, but broad, intense and well circumscribed.

Intensity of the Ape.v B eat.-Experience teaches one what pres­sure is needed to eradicate a normal beat. Pulsation of great power belongs especially to hypertrophied left ventricles.

S ystolic R etracfio'll at the Apex.-This may be normal , as in

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thin-chested individuals, or it may occur in hearts with broken com­pensation, or finally may be part of the picture of a concretio pe'ri­cardii cum corde. In the latter case, there will be noted also immo­bilit':!, of the ape.1: on change of position of the patient. This is a sille qua 11011 for the diagnosis of that interesting condition.

Vve can hurry over the other better known data obtainable from the apex beat in cardiac diagnosis, as, for example, its use as marker of the systole in determining whether venous pulsations in the neck are systolic or diastolic; its significance in favorable cases of the Stokes-Adams syndrome whereby the apex. indicates the time of the ventricles and the cervical veins that of the auricles; and its relation to the outer border of dulness in pericarditis with effusion. These and others are matters of general knowledge.

In conclusion, by way of illustration, I shall describe the quali­ties of the apex beat in a characteristic case of contracted kidney. Inspection reveals the beat in, or slightly without, the mammillary line. It may be powerful enough to convey its intensity even to the eye. Palpation reveals the fact that its inner and outer borders can be well marked by the thumb and index finger, and that it is 2-3 cm. broad. Further palpation with the index finger shows that the impulse is hard to eradicate. Diagnosis-without percus­sion or auscultation-dilatation and hypertrophy of the left ventricle alone.

That the minute examination of the apex beat has a diagnostic value quite out of proportion to the time often spent upon it, I hope that I have brought out in the preceding pages.