Seven Varieties Of Irregular Hearts
( Originally Published 1921 )
In every study there is always one hard and disagreeable task that must be performed before progress is possible. All through this book we have spoken in terms, as far as possible, that were not so technical as to require a dictionary. There are, however, seven names, and not easy ones at that, which the reader of this book must take the trouble to learn, before he can really appreciate the interesting and beautiful analysis of irregularities of the heart that form the basis of functional heart trouble.
The diseases of the heart as revealed by the polygraph and electrocardiograph have been classified into seven particular types of disorder. These types, as is true of all diseases, often merge one into the other, and two may be present at the same time; they are (1) sinus arrhythmia; (2) heart block; (3) premature contractions; (4) simple paroxysmal tachycardia; (5) auricular flutter ; (6) auricular fibrillation ; (7) alternation of the pulse).
It would at any time be easy in this big city to find people with each of these disorders.
Sinus arrhythmia is not of serious import and occurs as a physiologic phenomenon in young children. It can be reproduced at any time in comparatively young people by taking a long breath. It consists of a difference in the length of the interval between the beats. When exaggerated in children, it has sometimes led to the suspicion of inflammation of the heart muscle, and the children have been treated as invalids when they should have been playing out of doors. That can no longer happen under the advice of those who understand the use and interpretation of pictures of the heart beat.
As the impulse of the heart ordinarily begins in the auricle and is transmitted later to the The seven types of diseases of the heart may be remembered by the following mnemonic. Memorize the word "ships" and three "a"s. Also memorize this succession of letters: a-b-c-t-f-f-p. Mentally arrange the letters thus (omitting the "i" in ships) :Associate a word with each letter, remembering to add the word "paroxysmal" after "simple" in the fourth type.
Ventricle, we have the auricle and ventricle contracting in rhythmic succession. If disease destroys the muscular contiguity or conductivity, we have the auricle and ventricle out of relation to each other. This has received the name of heart block, and is beautifully shown by the electrocardiograph. It is due to this instrument that our knowledge of this condition exists.
In many people suffering from disturbed metabolism, we find the heart apparently missing an occasional beat. The fact is, however, that the heart is not as a rule missing a beat, but the beat is occurring prematurely and may pass unnoticed, while the succeeding beat is very large, and emphasises the length of the quiet interval. This is called premature contraction.
'When for any reason the ,heart abruptly be-comes rapid and suddenly ceases to be rapid, we say that the person is suffering from paroxysmal tachycardia. This has been a most difficult field of investigation and is still the ground of many disputed points. However, our instruments have disproved many previously held beliefs and pointed out not a few new facts.
One of the most recently recognised conditions is the extremely rapid tho regular auricle, usually 250 to 300 per minute, known as auricular flutter. It is always revealed by the electrocardiograph and occasionally by the polygraph. Auricular flutter is a condition in which the auricle of the heart is behaving literally like a wild bird held in the hand. It is beating at a rapid rate, usually three hundred beats a minute, and as the auricle is the origin of the heart beat this naturally, throws the rest of the heart into great commotion. Sometimes the heart responds to every second or third of these flutterings, and is rapid and regular; sometimes it responds to a few of them, but not regularly, and the heart is rapid and irregular.
This disease is one of the most interesting because it is perhaps the latest one to be thoroughly understood. It is also one of the most important ones, because when it is understood it is possible to remedy the condition. When we get the electric autograph of the heart beat, we find this disorder clearly set forth. Before the disease can be cured, ordinarily it must be converted into auricular fibrillation. This is done by the use of our principal heart remedy, digitalis, but in a particular way. Digitalis must be given in massed doses, so as profoundly to modify the chemistry of the heart, and then it must be completely withdrawn. Often, after it is stopt, or at least reduced to a small amount, the heart'will become practically normal, and for the time the person is entirely recovered.
Flutter of the auricle may be suspected when people describe attacks of rapid heart action, lasting for several days at a time, and not yielding to any ordinary methods of treatment. Its existence can be proved only by study of the record given by the cardiogram.
The knowledge of auricular fibrillation is one of the most important contributions of clinical medicine from the student of pathologic physiology. In this condition, there is a trembling palsy of the auricle, which transmits a vast number of impulses to the ventricle and the ventricle becomes rapid and irregular. It yields most strikingly to the use of digitalis.
Alternation of the heart can be detected in many instances only by the polygraph. This affection is of extreme importance it is a striking evidence of failure of the heart .muscle. It consists of alternation in the size of the beats.
Thus we see that irregularity of the heart beat is one of the things that may be most evident to a person who is suffering from heart disease. This is also apparent to one who examines the pulse or listens to the heart. The healthy heart beats come in regular succession and with equal force. They correspond in rapidity to the age of the person and the attendant circumstances. When the heart becomes irregular, it may miss beats or show new beats between the natural beats, and the force of the beats may not be even. Sometimes the sufferer feels this irregularity and is conscious of a pause in the heart's action. More often, these irregularities are not felt and are noticed only by the physician.
Irregularity of the heart beat is always an indication of some disorder of the heart, and it must not be lightly regarded on the supposition that it arises from the digestion, the nerves, or some other cause. To be sure, the, same poison that causes a violent disturbance of the digestion may also cause a disturbance of the heart, but the disturbance of the digestion does not of itself cause irregularity in a healthy heart.
Irregularities of the heart may have their origin in a disturbance of the mechanism that , causes the heart beat; namely, in certain parts of the heart muscle that have the property of originating the heart beats. Ordinarily, the heart beat commences at the part of the heart where the blood enters and spreads to the apex of the heart ; but when the heart is in a state of irritability, contractions may start at other places, and this naturally causes irregularity of the heart's action. It may occur even when the strength of the heart is perfectly good.
Again, there may be a defect in the heart which prevents contraction, when started, from spreading. In this instance, two parts of the heart may beat independently.
Another form of irregularity has a much graver significance than irregularity in rhythm, and that is irregularity in the force of the heart beats. The beats may be regular in time but may show great variations in force. This often means the loss of the power of the heart to contract, upon which depends its successful work.
A healthy heart rests between each beat and' the next and recovers strength for the next beat. When this does not take place, there occurs only a part of a beat and a corresponding irregularity in the strength of the pulse. When the heart is called upon for extra labor, there is a tendency to slow, forcible contractions, and possibly extra •beats every little while.
When pressure is taken off the heart by paralysis of the blood vessels or some similar cause, there is a tendency toward rapid beats quickly following each other, and a loss of beats at intervals. So in a person with Bright's disease and an enlarged heart and a high blood pressure, the former conditions are found. In a person who has been prostrated by an exhausting disease, like an attack of grippe, or typhoid fever, the latter condition is often present.
The treatment of irregularity of the heart beat must depend upon knowledge of its nature and cause. If there are slowness and extra beats due to high blood pressure, a plain diet' and out-of-door exercise are necessary. If the heart is rapid and drops beats on account of an exhausting disease, the person should be fed up and have rest. If the irregularity is due to beats originating in the wrong part of the heart, the source of irritation must be removed.
The same is true of things that have temporarily interfered with the passage of the wave of contraction from one part of the heart to another ; or, in cases of irregularity of the heart action due to permanent damage to the heart muscle, such as may happen after rheumatism or inflammation; or, as I saw in a striking case recently, it may arise from inflammation due to intestinal putrefaction. Then irregularity is apt to continue in spite of treatment, tho the heart may have strength in muscular power to such a degree that the irregularity of the beats does not necessarily produce invalidism.
An important duty in irregularity of the heart is to reassure the patient, since ordinarily, irregularities are not fraught with immediate danger.