CHAPTER VII

THE PHYSICAL EXAMINATION OF THE HEART AND ARTERIES

=Heart Boundaries=

In order to be able to estimate the departures from normal in the boundaries of the heart, it is essential that there be a definite appreciation of the boundaries of the normal heart in relation to the chest wall.

It is frequently stated that the right limit of cardiac dullness is normally, in the adult, just at the right border of the sternum. This is not strictly accurate. Careful dissections at the autopsy table and x-ray plates of the chest made at a distance of two meters from the tube show that the border of the right auricle is from one to one and a half and even two centimeters from the edge of the sternum at the level of the fourth rib, and on the living subject this can be also demonstrated. The right border of the heart usually is from 3 to 4 cm. from the midsternal line at the level of the fourth rib.

Again there is a term used in defining the apex, known as the point of maximum impulse. As this does not always coincide with the apex beat and with the outer lower left border of the heart, it would be better to use the term apex beat.

Normally, then, the cardiac dullness, the so-called relative cardiac dullness, begins above at the upper border of the third costal cartilage, as a rule, and taking a somewhat curved line with the concavity inward, descends to the fifth interspace or beneath the fifth rib from 9 to 10 cm. from a line drawn through the center of the sternum parallel to its length, the midsternal line. This seems to me to be a better method of recording the size of the heart than by the lines commonly used; viz., the nipple, or midclavicular, or parasternal line. Below, the cardiac dullness is merged into the tympany from the stomach and the dullness from the liver. At the sixth right costosternal articulation there is a sharp turn upwards forming at that point with the liver the cardiohepatic angle. At the fourth right cartilage or the third interspace, the dullness is from one to two centimeters from the edge of the sternum. We have then a somewhat pear-shaped area or triangular area with the apex at the apex of the heart. The so-called absolute cardiac dullness does not appear to me to be of any great significance. In reality it is the limit of lung resonance and may be greater or less, not so much on account of variations in the size of the heart, as of variations in size of the lungs and shape of the chest wall.

The really crucial question which should always be asked is, Is the heart enlarged or decreased in size? The position of the apex beat alone can not determine this, neither can the limit to the right of the sternum. The distance between these two points and the depth of the dullness at a distance of 5 cm. from the midsternal line on the left side, will give the size of the heart as nearly as can be obtained in the living subject. A series of measurements in normal adults average 13 to 14 cm. and 9 to 10 cm. respectively. For women they are about 1 cm. less in each direction.

The elaborate mechanism known as the orthodiagraph is probably the best means of determining the actual limits of the heart, but few men have such an expensive instrument, and, moreover, at the bedside such an instrument could not be used. From comparative measurements I concur in the belief of those who affirm that careful percussion will furnish equally as accurate limits.

The first step in making an examination of the heart is to expose the patient's chest in a good light, and, sitting at his right side, carefully inspect the chest. The position of the apex beat, heaving, bulging, retraction of interspaces, etc., can easily be seen if visible. After careful inspection has given all the data which it is possible to obtain, one next lays the palm of the hand over the heart and attempts to palpate the apex beat. The thrust of the apex in a hypertrophied heart can readily be felt, and one can feel whether the heart is regular, irregular, intermittent, or has other change in rhythm. The shock of the closing valves, particularly the aortic, can be felt, and that and the forcible apical impulse are very suggestive signs of hypertrophy and hypertension. Thrills may also be felt and can be timed in relation to the heart cycle.

=Percussion=

It is to percussion that we next proceed, and for the data in regard to the size of the heart, it is, for our purpose, the most valuable of all the physical methods of heart examination.

First and foremost we wish by percussion to learn the actual size of the heart, in other words what is ordinarily called the relative cardiac dullness. With the absolute dullness we are not concerned. That irregular area represents, as has been said, actually the =limits of lung resonance=. The heart may or may not be covered with lung; there may or may not be the incisura cardiaca. What I wish to insist upon is that the size of the area of absolute dullness can give us no data in regard to the size of the heart. What we must endeavor to learn is the actual size of the heart as nearly as our crude means will permit.

Light, very light, almost inaudible percussion, what Goldscheider called "Schwellungsperkussion," must be practiced. Use the middle finger of the right (left) hand as the hammer and the last joint of the middle finger of the left (right) hand pressed firmly against the chest, as pleximeter. I believe it is better to place the pleximeter finger parallel to the boundary to be limited although some place the finger perpendicularly, that is, pointing toward the boundary. Now and then it helps to bend the pleximeter finger at the second joint, hold it perpendicularly to the chest wall, and strike the joint directly in line of the finger. This in my hands has been of great assistance in percussing the limits of the heart dullness. Pottenger's "light touch palpation" is a modification of the light palpation and, to my mind, has no very special advantages. Auscultatory percussion is of great value at times. The bell of the stethoscope is placed over the portion of heart uncovered by lung (should such be the case), and with this point as a center the chest is lightly and quickly tapped along radii converging toward the stethoscope. One soon learns to recognize the change of pitch as the tapping reaches the border of the heart. It is well to use all methods, especially in difficult cases, and to compare the results. Personally I have found that by light percussion I can limit with much accuracy the upper, right, and left borders of the heart.

There is much to be gained by using light percussion. Strong blows set in vibration not only the underlying structures, but also more or less of the chest wall. We wish to avoid this source of error, we do not wish to differentiate by pitch alone. Finally one's pleximeter finger becomes, after long practice, so sensitive to changes in the resonance of structures lying below it, that there is actual feeling of impairment to the slightest degree. This delicate touch is what we should endeavor to cultivate.

It is at times of advantage to use immediate percussion. This is done by bending the fingers of the striking hand, bringing the tips in a line and striking the chest lightly with the four fingers as one finger. Some find it easier to percuss the dullness due to the heart in this way than by mediate percussion.

The little hammer and hard rubber, celluloid, bone, or ivory pleximeter does not seem to me to be nearly as good as the fingers. Moreover, one always has his hands, but may forget his hammer and pleximeter.

=Auscultation=

In auscultating the heart I prefer the binaural stethoscope of the Ford pattern. The recent substitution of an aluminum bell for the hard rubber bell is an improvement. Personally I do not favor the phonendoscope or any of the new patent non-roaring instruments now for sale by urgent instrument makers. The phonendoscope has its uses, for example in auscultating the back when a patient is lying in bed or in listening to the heart sounds when a patient is under an anesthetic; but for differentiating the murmurs and for heart diagnosis, I much prefer the regular bell stethoscope.

In arteriosclerosis the two places over which it is important to listen are the apex and the second right cartilage, the aortic area. Over the former, one gains data in regard to the strength of the heart as indicated by the first sound, over the latter point, one learns of the tension in the aorta by the character of the sound produced when the aortic valves close.

The hypertrophy of the heart in arteriosclerosis is invariably due to the enlargement and thickening of the left ventricle. From the nature of the position which the heart assumes in the thorax, this enlargement is downward and to the left. The apex beat will therefore be found in the fifth or sixth interspace, and definitely at an increased distance from the midsternal line. As stated above, it is most important that this distance be accurately measured and put down in the notes of the case for future reference. No satisfactory prognosis can be given unless this is done, for the gradual increase or the decrease under treatment in the size of the heart can thus be definitely known, and, knowing the other factors, a prognosis may be given which will be of some value to the patient.

=The Examination of the Arteries=

It is exceedingly difficult at times to affirm definitely that an artery, the radial for example, is actually sclerosed. Much depends on the sensitiveness of the fingers of him who palpates, and much upon the relation of the palpated artery to the surrounding, chiefly underlying, structures. In the examination of arteries it is well to inspect the body for the pulsations caused by them. Frequently an exceedingly tortuous artery, such as the brachial, may be seen throughout its whole extent and yet the radial appear little, if any, thickened by palpation. Again the artery of a pulse of high tension which is small in size but full between the beats, may not be as sclerosed as one which collapses and feels much softer. It is difficult to obtain accurate data in regard to the tension in an artery by feeling it with the fingers of one hand. One should use both hands. With the middle finger of the right (left) hand the artery is compressed peripherally, that is, nearest the wrist. The blood is then pressed out of the artery with the middle finger of the left (right) hand, so as to obliterate completely the pulse wave and the two or three inches between the middle fingers are felt with the index fingers. By holding the finger firmly on the artery near the wrist so as to block any wave that may come through the palmar arch by anastomosis with the ulnar artery and by releasing pressure on the proximal middle finger, some idea may be had of the degree of pulse tension. However, no amount of practice can more than approximate the tension and when one is surest that he can tell how many millimeters of pressure there are, he is apt to be farthest wrong when he checks his guess with the sphygmomanometer.

Much may be learned from carefully palpating the peripheral arteries, and, as a rule, the sclerosis of these arteries means general arteriosclerosis, although there are many exceptions to this.

A more recent method, and one which in the author's hands has been found to be valuable, is that proposed by Wertheim-Salomonson who palpates the artery not with the ball of the finger but with the fingernail. The finger is held so that the nail is perpendicular to the surface of the skin and the artery is felt with the end of the nail. The sensation is perceived at the root and makes use of all the sensitive nerve endings there. In this way it is possible to feel the arterial wall distinctly, and a little practice will enable one to determine whether or not the vessel wall is thickened. It is also possible to determine with a considerable degree of accuracy the diameter of the artery and the size of the wall when the current is cut off by pressure on the proximal side of the artery. It is best to have a firm background when this "fingernail" palpation is used. This may be obtained by palpating the radial artery against the lower end of the radius.

Probably the best method of palpating the arteries, especially the radial, to determine the degree of sclerosis and thickening, is to use the tip of the finger and roll it carefully over the artery. The tip of the finger is exceedingly sensitive and, moreover, it is a firmer palpating surface than the ball, thus enabling one to appreciate degrees of sclerosis which could not be differentiated by palpation with the soft yielding ball. This finger tip palpation is well illustrated in the figures here shown. (Figs. 57 and 58.)

=Estimation of Blood Pressure=

It must be borne in mind at the outset that arteriosclerosis and high blood pressure are not always associated. As a matter of fact in the severest grades of senile arteriosclerosis the blood pressure is usually below the normal for the individual's years. However, as high tension is a frequent factor in the production of arterial thickening, blood pressure readings are of importance.

The instrument which one uses is of minor importance provided it is properly standardized. The most important feature of the instrument is the cuff. This must be 12 cm. wide and be long enough to wrap around the arm several times so that the pressure is evenly distributed over the whole arm and not over a small portion. One mercury instrument we had in the hospital was reported to be at great variance with a dial instrument. This mercury instrument was provided with a cuff which was short and was tied around the arm by means of a piece of tape. This caused a tight constriction over a small area and rendered the estimation too high. A new, long tailed cuff easily remedied the apparent defect in the instrument.

In taking blood pressures the difference from day to day of 10 or even 15 mm. of systolic pressure has no great significance. Fluctuations of the systolic pressure alone, it is insisted upon, have very little meaning. One must take the whole pressure picture into consideration and determine how the picture changes in order to draw any conclusion in regard to the state of the blood pressure. Failure to pay attention to this evident point has caused much futile work to be written and published.

It is well to emphasize again the point that the blood pressure picture consists of the systolic, the diastolic, the pulse pressure and the pulse rate.

=Palpation=

Hoover has called attention to the direct palpation of the femoral artery just below Poupart's ligament as a more accurate index of the pressure in the aorta than the palpation of the radial artery. Possibly one can obtain a more accurate estimate of the blood pressure in this way. This, however, is open to dispute. To estimate the blood pressure by palpating the radial artery is most deceptive. In about 75 per cent of cases one can tell fairly well whether the pressure is abnormally high or abnormally low. Small variations are impossible to determine. Unquestionably it is most advantageous to get into the habit of palpating the femoral artery and checking the result with the sphygmomanometer so that the fingers may be trained to appreciate as accurately as possible changes of pressure.

It may be that one day when the instrument is needed it is not at hand. A well-trained touch then becomes a great asset.

=Precautions When Estimating Blood Pressure=

There are certain precautions which must be strictly observed when deductions are drawn from the manometer readings. The psychic factor must be reckoned with. Any emotion may cause marked variations in the pressure. Excitement and anger are especial sources of error. Even the slight excitement arising from taking the first blood pressure on a nervous patient especially is apt to give false values. Usually the readings must be taken many times at the first sitting and the first few may have to be set aside. Worry is a potent factor in raising the pressure. A walk to the physician's office, especially if rapid, has its effect.

The position of the patient when the blood pressure is taken is important. Usually in the office the pressure is taken when the patient sits in a chair. He should assume a relaxed, comfortable attitude. The readings should be made at the same time of day and at the same interval between meals. The pressure in both arms should be measured and comparisons should be made only between readings on the same arm. These precautions may seem useless and even somewhat trivial, and the conditions difficult to control. But unless they are carefully observed the readings will be false, no comparisons can be drawn between the readings on different days, and the instrument will most probably be blamed. I have known this to happen so often that I can not emphasize too strongly the importance of controlling all the essential conditions which go to make accurate work.

=The Value of Blood Pressure=

In the past few years there has been a veritable avalanche of blood pressure instrument salesmen who have covered the country, sold instruments, and have made many startling claims for the instrument. They have emphasized its value out of proportion to what the instrument can do even in the hands of one familiar will all the defects. Consequently it is not necessary to emphasize the value of blood pressure. It seems best to utter a few words of caution in regard to its interpretation.

The value lies not in the occasional estimation compared with some other one reading, but in the frequent estimation and in the visualization of the blood pressure picture. For the great majority of diseases the blood pressure has no particular value except to show that the circulation is not materially disturbed. The limits of normal are rather wide, so that consideration of the patient's age, sex, build, etc., will give us some idea of a base line, so to speak, for any one person. Wide departures from relatively normal figures are important, but are not diagnostic or, rather, pathognomonic. I can not help but feel that the diastolic pressure is _the_ most important part of the blood pressure picture. Persistent high diastolic pressure means increased work for the heart, which, if acting for a long time against the high peripheral resistance, must eventually hypertrophy. The arteries become thickened, lose their wonderful elasticity, fibrous tissue is deposited in their walls, and the vicious circle is established which leads to pathologic hypertension.

Blood pressure readings must be intimately mixed with brains in order to be of any great value in diagnosis or prognosis.