In our ordinary means of investigation, it often exceeds our best powers of discrimination, to distinguish satisfactorily between functional and structural disease; and this difficulty, I apprehend, will not be removed by the use of the stethoscope, although I am well persuaded it will be very materially lessened. Both humanity towards the patient, and a regard for our own reputation, demand that we should use very great caution in forming our opinion on these occasions, and still greater in pronouncing it.
Inordinate action of the heart arises from many influential causes, both of a moral and physical nature. Nervous palpitation is of common occurrence. Intermission of pulse is not unfrequent; but I have had occasion to see most experienced practitioners mistaken concerning the true nature of this affection. It occurs as a sympathy with a morbid state of the brain, the stomach, and also the liver; but most frequently, according to my observation, when the stomach of an individual of nervous constitution is disordered with permanent indigestion.
The most remarkable cases of intermittent pulse which have occurred in my practice, have been connected with faulty action of the digestive organs, and of the liver especially, in gouty persons. We know how remarkably the gout affects the nervous system; and I can scarcely offer a stronger proof of it, than this kind of influence upon the heart; for although we meet with examples of the same kind of irregular action, in a disordered state of the digestive organs, in persons free from all disposition to gout, yet in such instances it is neither so permanent nor so remarkable.
I was consulted by a gentleman ill with gout, who related to me that, a few years before, he had been troubled with intermittent pulse for the long space of four years; and, during this period, his mind was alarmed with many gloomy apprehensions. His digestive organs were much disordered: medicine had given only partial relief. Quite suddenly, a painful and regular fit of gout took place, for the first time. Immediately the action of the heart became regular, and has so continued from that period.
I have met with similar instances less strongly marked.
In various affections of the heart, and also of the aorta, I have derived very useful information, and practical instruction, from the employment of the stethoscope. In the case of a female, the instrument, applied to the epigastric region, conveyed to the ear the peculiar sound which is compared to the blast of a pair of bellows strongly used, and which was attended with occasional pain, especially after taking food. The repeated application of leeches, with the use of sedative medicine, afforded permanent relief.
When we consider that, from the examination of the pulse at the wrist, we obtain information only of the action of the left ventricle of the heart, and that by means of the stethoscope we are made acquainted with the action of both ventricles and both auricles, the value of the instrument must appear unquestionable.
This fact, that the pulse at the wrist does not indicate the state of the whole heart, is important in a practical as well as a physiological point of view. The pulse, in certain diseases, may be weak and small, when the action of the heart is energetic, and which is to be ascertained by the stethoscope. On the other hand, there may be more energy in the action of the pulse than in the heart generally. The practitioner will receive very material instruction with regard to the use of the lancet, in these indications; and will know with more accuracy when he should prefer local to general bleeding.
In the first trials with the stethoscope, it is extremely difficult to distinguish the action of the ventricle from that of the auricle; and this confusion is greater if the heart be acting with more than ordinary frequency.
The motions of the left cavities of the heart are chiefly perceptible in the space comprised between the cartilages of the fifth and seventh ribs; and of the right, at about the middle of the sternum, or sometimes rather lower.