SOME ASPECTS OF CHEST PAIN

In every field of medicine the complaint which most commonly causes the patient to seek the advice of a physician is pain. The timing of the patient‘s visit will be governed by his personal sensitivity or pain threshold, and by the degree of his fear of this symptom.              .
In the course of our clinical work we have all been puzzled at times how we may evaluate rightly the main forms of pain arising in the chest. So common is this symptom that in barely three months since I decided on this subject I have treated 70 cases of chest pain.
On looking at the subject of chest pain more closely I soon realized that the scope is vast, comprising as it does most of medicine, for there are few bodily structures which have no link direct or indirect with the chest. Certain aspects  only can be considered, so I shall concentrate mainly on the less usual extra- thoracic causes.
The subject is important for hardly a day passes in which we as physicians do not have to make a decision as to the import of a pain complained of in the chest. Because of the element of fear and the common knowledge that “Anginal pain” is associated with sudden death, we have to make our assessment as carefully as possible, giving strong reassurance where this is reasonable and firmly giving the alternative diagnosis, which will do more than anything else to allay fear by giving a reason for this dreaded symptom. The slightest hesitation on the part of the doctor is interpreted as unwillingness to tell the patient the worst.
Frequently he will say, “it is just wind, Doctor”, and look at you hopefully  to confirm his suggestion. In many cases it is just this, and how astonishing and severe a discomfort this trivial ailment can produce; but how is it possible to confuse this cause of chest pain with others so much more serious? Unfortunately it must be added at once that flatulence is a common accompaniment of other causes of chest pain.
The key to the solution of many problems of diagnosis in diseases of the chest lies in a knowledge of the pain pathways of the viscera.
This subject was first seriously studied by Henry Head whose centenary was celebrated last year. His findings were first accepted, later rejected, but now once again are the basis of present day thought on the subject. Sir James Mackenzie also taught that the Theory of Disturbed Reflexes was the foundation of the symptoms of disease. Expressed as simply as possible, and leaving neuro-physiological details to the text books (e.g. Pottenger) the salient facts are as follows:
Chest Pain may be transmitted by the voluntary, the sympathetic or the parasympathetic nervous systems; by each one, or all three systems.            .
Through afferent links in the sympathetic ganglia the viscera are inter connected. These ganglia in turn are connected with the sympathetic chain and grey communicating fibres link up nodes in this chain to the segments of the spinal cord, i.e. linking up with several segments of the voluntary nervous system-from Dl to L3.
From the cord pass back in the white communicating fibres motor impulses to the sympathetic ganglia and on to the viscera, mainly inhibitory of sphincters.
The parasympathetic nervous system subserves much the same function. The cranio- bulbo-sacral outflow is mainly in the vagus and pelvic nerves and the ganglia in this case are in or near the organs concerned.
The organs supplied by vagus include for practical purposes all the viscera (Table A et seq.) (Samson Wright and Pottenger).
TABLE A
Vagus (X) C.N. : Sensory Supply
1.  Base of tongue, palate, pharynx, oesophagus, stomach, duodenum, jejunum, ileum, ascending colon
2.  Entire respiratory tract, epiglottis down
3.  Heart
4. Biliary tract
5.  Auricles and external auditory meati
Vagus (X) C.N.: Motor Supply
Large intestine to descending colon,
bronchi. liver, spleen
Soft palate, pharynx, upper cesophagus
Larynx, stomach, small intestine
Suprarenals and kidneys
Table A shows the sensory and motor distribution of vagus (X). The sensory and motor nuclei of the vagus (X) are closely bound by connecting fibres which cause reflex action to be very readily transmitted from the afferent fibres of one  viscus to the efferent fibres of another. Similarly for the cranio-bulbar connections with the sensory division of the Vth cranial nerve. E.g. pressure on the’ eye-ball reflexly slows the heart. In the chest the vagus (X) forms connections with the sympathetic through the inferior cervical ganglion forming with them the Esophageal, cardiac and pulmonary complexes.                 ,
The area of reference may involve several spinal segments since, according to the strength of the stimulus, few or many neurones may be involved spreading  by the three neurone response system up and down the cord. E.g. the spread of  anginal pain over the areas supplied by cervical 3, 4 and 5, and dorsall, 2 and 3,  to arm, neck, jaw, shoulder, elbow and fingers, and the area of reference may  vary from day to day.
It will be seen, therefore, that there are three possible pathways for pain  through the voluntary, the sympathetic and the parasympathetic parts of the  autonomic nervous system, with the possibility of a spill-over from one to  another and at higher and lower levels in the cord. All this makes for difficulty in locating the cause of a chest pain. The viscera have a high latent pain sensitivity which is provoked by inflammation or distention. The superficial type of pain may be abolished by a local anresthetic or cooling spray and this is effective  even in angina pectoris. Deep pain On pressure follows the muscle groups  (myotomes) rather than the dermatomes and ,therefore is often at a lower  segmental level than nerve root emergence. It should be mentioned also that in  the case of chest disease there is commonly atrophy of the superficial integument  over the area of reference, usually the infra-clavicular and collar region supplied by C 3, 4, 5, this even when the disease is remote from this area.
This segment of the spinal cord 03-5 is of greatest importance since it represents phrenic nerve root distribution, the pleural and peritoneal surfaces of central diaphragm, so linking it with upper abdominal conditions.  It is, moreover, commonly affected by lesions of the spine, spinal cord and  roots at this level. By remembering that its somatic dermatome is the collar  and infraclavicular regions, and that it is immediately contiguous below with  dermatomes D2 in the pectoral region (the intervening roots going to the arms)  many errors will be avoided.
Before returning to the clinical aspect it is interesting to note that a similar  phenomenon known as translocated injury has recently been discovered in other  realms of nature. (C. E. Yarwood in Nature, Vol. 192, p. 887.) Leaves of the Pinto bean, cowpea and National pickling cucumber have been shown to respond in pairs to heating.
If one of a matching pair of leaves is heated and killed the matching member  of the pair sustains substantial injury although the connecting parts of the  plant are apparently unaffected. If the heated leaf is cut off within four hours, the damage to the second leaf does not occur. The mechanism here is chemical.
As has been said, pain may appear at an area quite remote from the organ responsible and this gives rise to some of our clinical difficulties in diagnosis.  Perhaps the best known example is gall bladder disease expressing itself by pain at the tip of the right shoulder. In this case, as in others to be mentioned, the explanation is that in the embryo the structures were close together and in  course of development the organ has migrated away from its area of reference.
The possible sources of origin of pain in the chest are legion since it may arise  from any tissue in the thorax, from several structures outside, and, to make  matters more difficult, it is not uncommon to have pain from several sources  simultaneously.
Lesions of the skin need only to be mentioned to be dismissed since they are  visible and obvious causes.
A neurological cause which has painful cutaneous manifestations affecting the  chest wall, herpes zoster, arises insidiously but usually declares itself within 10  days and the burning persistent pain is characteristic of some form of acute  neuritis so should seldom occasion difficulty. Herpes forms the link which  reminds us that it may be the harbinger of acute myelitis with corresponding  root pains. This in turn reminds us of the many possibilities of spinal cord  tumour with similar root pains which may well be referred to the chest.  Fibrositis, fibromyositis and the drooping shoulder syndrome with trigger  points locally or at the superior medial angle of the scapula and with distribution  to chest by the intercostal nerves, again give rise to confusion quite occasionally, by producing prsecordial or left arm pain.
Various forms of myalgia of the pectorals and intercostals can cause difficulty. In epidemic form it is known as Bornholm’s disease, but there is usually some constitutional disturbance by which to identify this.
Tenderness and soreness over any or” the costochondral junctions (the costo- chondral syndrome), may give rise to much anxiety, being ill defined, recurrent and subject to the same radiation as anginal pain. The 2nd to 4th ribs are most commonly involved. Location of the tender bulbous junctions gives the diagnosis and a similar syndrome may be found related to the xiphoid process.
These possibilities have only to be remembered to be recognized at once. It is seldom that diseases of the breast, being relatively superficial, will give rise to difficulty. Unless where a tiny undetected primary growth gives rise to secondaries within the chest or spine, when root or referred symptoms appear.
A very important group of causes of chest pain are those arising from cervical and dorsal spine, where osteoarthritis, spondylitis, rheumatoid arthritis, vertebral epiphysitis, herniated discs, tuberculosis and metastatic neoplastic deposit may all produce impingement upon nerve roots the sensory distribution of which is upper chest and may give rise to pain difficult to distinguish from angina pectoris. The pain is often sharp .01′ tearing and it may be precordial and associated with a sense of tightness. In so far as some of these are degenerative diseases they are common accompaniments of degenerative heart disease.  Among these the rheumatoid form of spondylitis is quite frequently associated  with valvular heart disease, still further complicating diagnosis.
In osteoarthritis of this region, by narrowing of the foramina through which  the nerves emerge, there is a dull ache over the shoulder or pectoral region simulating anginal distribution. Or there may be burning or stabbing over the praecordium from D2-4. Pain in this case is much affected by activity. Osteoarthritis in the neck is commonly initiated by a cervical disc lesion which is usually the result of trauma, especially “whiplash” injury as in car accidents. The onset can be gradual with neck pain later extending into pectoral region, arm, hand and fingers. X-ray and investigation of the electrical reaction of muscles involved will establish diagnosis in these cases. Finally in this group is “straight-back” syndrome where the normal curve of the upper dorsal spine is straightened. This causes confusion because of apparent heart enlargement on X-ray and systolic murmurs, basal in position, produced by compression of the great vessels.
Marked kyphoscoliosis and compression fractures of vertebral bodies are obvious causes of referred pain if only remembered. Usually the difference made to the pain by changes of position will serve to distinguish these. Osteoporotic collapse produces similar effects.
To complete this outline of the extra-thoracic causes of chest pain it is necessary to consider briefly disorders of the liver, biliary tract, pancreas and upper gastro-intestinal tract. The pain pathways for stomach, liver, biliary tracts and pancreas are the same (Table A) hence the difficulty in sorting out epigastric pain.
Biliary tract pain in its acute form has often been mistaken for coronary pain and vice versa, and diseases of gall-bladder and heart are often co-existent.
Unfortunately electrocardiographic changes occur in many functional and organic abdominal disorders, as in spasm and distension of biliary ducts or hiatus hernia. It may be that reflex changes in coronary blood flow are produced by mechanical irritation of vagal fibres. Cardiac discomfort and serious arrhythmias are readily produced in the damaged heart. Where gall bladder disease and coronary disease co-exist, the latter is helped by. removal of the gall bladder. (Strangely enough the risk is relatively, low, 10-15 !per cent, and even Stokes-Adams attacks generally respond.) (Reich and Fremont.)
Again acute pancreatitis is often confused with acute myocardial infarction. Both have high epigastric pain, shock and collapse. Pancreatic pain is usually constant and boring. Posterior radiation and relief on sitting up are characteristic with guarding of the left side: of the epigastrium. The serum amylase and lipase levels may be elevated and are of great assistance in diagnosis.
Amylase well above 200 units/lOO ml. (Somogyi)
Lipase   ”              “150,      ”
Electrocardiographic changes are marked due to coronary spasm and electrolyte changes may alter the S.T. segment and T. waves to resemble occlusion. The exact position of the pain depends on the part of the gland affected.
relation to angina. Unfortunately the exceptions are almost as frequent as the rule.
TABLE D

So from this brief survey it would appear that usually the pattern of chest pain is readily diagnosed. There are many cases, however, where because of multiple pathology, psychological overlay, or because it is possible for different diseases to use the identical pain pathways, there may be simulation of serious disease. This requires painstaking elucidation, but finally there are only a few cases where the solution remains obscure.
In conclusion. My period of office has been a testing one for the Faculty. By death we have lost several members, some very distinguished, and our rate of replacement has not equalled these losses in numbers. We have come under heavy fire from the homreopathic lay bodies for our apparent lack of action in the direction of propaganda, but more recently they have, I think, been made to see our reasons and to understand our present policy a little better. I believe it to be essential that we work independently but in full accord with the Lay Associations, having identical, objects in mind; their work directed to the general public and ours to the profession. We doctors must try to lose a little of our reserve and promulgate our views more vigorously among our professional colleagues. I feel that only in this way are our numbers likely to increase. If we could each convince one colleague of the essential rightness of our way of thinking the whole Faculty would take on a new lease of life.
Once again I feel that I must mention that the Faculty cannot prosper unless those members who reside within the Greater London area make a point of arranging their work so that they attend regularly. That it can be done is shown clearly by those who at much greater sacrifice come long distances from the
Provinces with great regularity and, I trust, considerable profit. (At the moment I realize that I am “preaching to the converted”, but I hope that this message will arouse guilt feelings in those for whom it is intended.) Permit me to pay tribute to the excellent work of our Hon. Secretary whose hard work, clarity of thought, and ready wit have helped us on many an occasion.
And now it is with great pleasure that I hand over the torch to the most distinguished of our Scottish members, Dr. T. Douglas Ross, whose wisdom and knowledge is the guiding light of our Scottish Branch, in every confidence that under his leadership the Faculty will again flourish.
REFERENCES
·         Henry Head, Brain; Vol. 84, Pt. IV., 1961.
·         Sir James Mackenzie, B.M.J., 1, 147, 1921.
·         Pottenger, Francis, Symptoms oj Visceral Disease (U.S.A.).
·         Samson Wright, Applied Physiology (Oxford Med. Pub.).
·         C. E. Yarwood, Nature, 192, p. 887.
·         N. E. Reich and R. E. Fremont, Chest Pain (Macmillan Co. N.Y.), 1961.
·         Paul Wood, Diseases oj Heart and Cinulation (Eyre & Spottiswoode).
 
Source: The British Homoeopathic Journal