Angina pectoris paravertebral alcohol block for the relief of pain

ANGINA PARAVERTEBRAL

ALCOHOL

GEORGE

I.

PECTORIS* BLOCK FOR THE RELIEF

SWETLOW, M.D., BROOKLYN,

S

INCE the original suggestion

of cervical sympathetectomy by Francois Franck and the first actuaI surgical interference for the rehef of angina pectoris by Jonesco of Bucharest in rgr 6, surgeons have attempted to relieve the agonizing pain incident to cardiovascrdar disturbance. That the surgica1 attempts are based on insuffrcient and inadequate anatomica1, physioIogica1 and pathoIogica1 evidence is ampIy borne out by the great variety of surgica1 procedures attempted. ANATOMICAL

AND PHYSIOLOGICAL

CONSID-

ERATIONS

Before reporting our procedure, a brief description of the cardioaortic afferent nervous system wiI1 be discussed. The method used is based upon the foIIowing anatomica and physiologica facts. The cardiac pIexus is brought into contact with the sympathetic system through three cardiac nerves, i.e., the superior, middIe and inferior cervica1 cardiac nerves. These nerves originate from the superior, middIe and inferior cervica1 gangIia. The right superior cervica1 cardiac nerve enters the deep cardiac pIexus and gives a few branches to the anterior surface of the aorta. The Ieft superior cervica1 cardiac nerve joins the superhcia1 cardiac plexus. It is of importance to note that the superior cardiac nerve communicates freeIy with the middle cardiac nerve and with the superior cervica1 cardiac branch of the vagus. The middIe cervical cardiac nerve arises from the middIe cervica1 gangIia. Often this nerve and gangIion are entireIy absent. Both the right and Ieft middIe cervica1 cardiac nerves end in the deep cardiac pIexus. The middIe cervica1 cardiac nerve inoscuIates in the neck with the * Read by invitation

F.A.c.P.,

OF PAIN

L.L.B.

N. Y.

superior cervica1 cardiac nerve and the inferior IaryngeaI nerve of the vagus. The inferior cervica1 cardiac nerve arises from the inferior cervica1 gangIion and at times from the first thoracic gangIion. It inoscuIates with the middIe cervica1 cardiac nerve and the inferior cardiac nerve. The Iowest cardiac nerve terminates in the deep cardiac pIexus. The vagus nerve aIso ends in the deep cardiac pIexus. The nerves of the heart are derived from the cardiac pIexus. These nerves pass down aIong the aorta and are distributed to the auricles. From there they accompany the coronary arteries aIong the auricuIoventricuIar groove, forming the coronary plexus. From this pIexus branches are given off to the ventricIes. The ascending aorta has nerve fibers which are in reIationship through the rami communicantes with the first six spina thoracic segments. There is some question as to whether the afferent fibers of the inferior cardiac nerve pass to the fourth, fifth, sixth and seventh cervica1 nerves. There is some evidence to the contrary. First, cIinicaIIy, it is rare for pain to appear over the dermatomic segments suppIied by the fourth, fifth, sixth and seventh cervica1 roots. EmbryoIogicaIIy there is aIso some evidence against this occurrence. Head showed that afferent fibers from the heart enter the upper cervica1 and thoracic segments, extending from the first to the seventh dorsa1 segments. Apparently in the deveIopment the fibers going to the Iower cervica1 nerves are not deveIoped from the inferior cardiac nerves. AI1 three cardiac nerves convey motor impuIses to the cardiac pIexus. Ranson maintains that most or a11 of the constrictor fibers to the aorta and coronary vessels come through the superior cardiac nerve. The sensory afferent impulses from

before the American Society of RegionaI Anesthesia,

88

Stated Meeting,

February 4, 1930.

NEW SERIES VOL. IX,

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the middIe and inferior cardiac nerves reach the spina cord through the rami communicantes. They enter into the thoracic segments, extending from the first to the seventh segments. These sensory afferent fibers are fineIy myehnated. Edgeworth maintains that such fibers pass into the central nervous system by way of the rami communicantes into the upper thoracic segments. The accompanying diagram (Fig. I) is a representation of what is generaIIy known and accepted concerning the anatomica and physioIogica1 connections of the cardiac nerves to the spinal cord. Hypothetical nerves, such as a special depressor nerve and the vertebra1 nerve and structures seen in comparative anatomica studies but not estabIished for human beings, have been passed over IightIy in this discussion. Since every conceivable combination of operations has been performed and since the beneficia1 resuIts are far from constant, an expIanation of the varying resuhs may be offered. CarefuI examination of the diagrammatic representation of the nervous mechanism shows quite concIusiveIy that not only are the cervica1 gangIia in union with one another, but aIso that the cardiac nerves inosculate with each other as we11as with fibers of the vagus. It is quite evident that the removal of any combination of ganglia and cardiac nerves Ieaves other pathways for pain stimuIi to proceed to the brain stem and cord. Even if one were boId enough to attempt in a human the extirpation of a11 of the cardiac nerves on both sides, together with both vagi (if it were possible), impulses from the cardiac pIexus and aorta would stiI1 pass into the spinal cord by means of the rami communicantes through the aortic nerve. They wouId enter into the cord from the first to the seventh dorsa1 segments. Since most of the experimenta work has been done on Iower animaIs and since the operations on man have shown no definite, constant, results, the foIIowing

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question arises: What are the pathways for cardiac pain ? At present the answer is not known. We do know, however, that irrespective of the pIace of origin of painfu1 stimuIi and irrespective of the cardiac nerves through which they pass, they must uItimateIy pass into the spina cord or brain stem to trave1 by way of the spinothaIamic tracts to the thaIamus and t&imateIy reach the sphere of consciousness. The probIem can be soIved by ascertaining definitely this point of entrance of the pain conveying fibers. With this knowIedge, a mechanica interruption of the continuity of these entering fibers would prevent the pain stimuli from entering the cord. Head and MacKenzie suggested that painfu1 stimuIi passed from the heart by means of sympathetic fibers to dorsa1 root gangIia. The pain was thus referred to the surface dermatomes suppIied by the irritated dorsa1 root ganglia. Any method, therefore, that wouId indicate through which dorsal root gangIia the mass of pain stimuli are passing, wouId indicate the exact areas to appIy surgica1 intervention in order to block this entrance of pain impuIses into the spinal cord. Another neurophysioIogica1 conception is important. CeIIs in the dorsa1 root gangIia that are being bombarded are hyperirritable to externa1 stimuIi. If a dermatome supphed by an irritabIe dorsa1 root gangIion is scratched with a pin or irrita.ted by heat, it wiI1 produce a greater sensory reaction than would a skin area suppIied by a normal dorsa1 root ganglion. Based on the foregoing premises, carefu1 protopathic and epicritic sensory tests are made so as to determine the dorsa1 root gangIia that are being bombarded by pain stimuli. The object, therefore, is to destroy the poorIy myeIinated afferent sensory fibers from the heart which are passing through the sympathetic cords to enter a dorsa1 root gangIia. This can be done by destroying either the dorsa1 root gangIia or the afferent sensory, poorly myehnated fibers runningv in the svmoathetic cords. y I

Dv

I \

DVI

NEW SERIES VOL. IX, No. I

EFFECT

OF

SwetIow-Angina

ALCOHOL NERVE

INJECTED

INTO

TISSUE

DogieI in his researches showed that the afferent sensory sympathetic fibers are fineIy myehnated. It is also known that these lightly myeIinated afferent sensory sympathetic fibers arborize about certain ceIIs in the dorsa1 root gangIia, i.e., DogieI ceIIs. With the injection of aIcoho1 into the dorsal root gangIia or into the sympathetic fibers in the vicinity of the dorsa1 root ganglia an intense WaIIerian degeneration ensues. In our cases we have used 3 to 5 C.C. of an 80 per cent to 85 per cent soIution of aIcoho1 paravertebraIIy in order to produce such destruction. CLINICAL WAY

OF BY

EVIDENCE CARDIAC THE

CONCERNING PAIN

SUBJECTIVE

AS

THE

PATH-

ASCERTAINED

RADIATION

Irrespective of the pIace of origin of the painful stimuIi which give rise to cardiac pain and of the nerves through which they pass, these impuIses must uItimateIy pass into the spina cord or brain stem to trave1 by way of the spinothaIamic tracts in the spina cord to the thalamus and thus uItimateIy reach the sphere of consciousness. Before entering the spina cord, however, these pain impuIses, as with any pain impuIses, must first enter the dorsa1 root gangIia, so as to give rise to the phenomenon of referred pain. It is upon these basic physioIogic principIes that these subjective pain areas, as compIained of by the patients, are expIained. Of further interest are the observations, that the areas compIained of are parts of the body surface relegated in nearIy a11 of the cases to dermatomic segments that are suppIied by those spinal nerves found between the eighth cervica1 and seventh thoracic segof the ments. In a carefu1 examination histories personaIIy taken, as we11 as a perusal of the Iiterature of many cases of pain due to angina pectoris, coronary disease and aortaIgia, one is quite forcibIy

Pectoris

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struck with the fact that the radiation of pain is reIegated quite consistentIy to those areas of the body suppIied by the eighth cervica1 down to the sixth or seventh dorsa1 (C VIII to D VII) nerves. These observations aIso reveaIed that any part or a11 of the chest may be subjectiveIy referred to as the seat of the pain. Although it is true that at times the patients compIain of pain in the back of the head (C I and II) or in the ear (C II) and at times in the Iower jaw (trigeminal), yet it is worthy to note, that these two former sites are of rare occurrence while the Iast site is indeed a curiosity. A compIaint of pain along the outside of the arm, which is suppIied by the fourth, fifth, sixth and seventh cervica1 nerves is of such rare occurrence, that its actua1 existence is greatIy to be doubted. In fact, anatomicaIIy, it is quite IikeIy that no afferent sensory fibers of the inferior cardiac never pass through these four Iatter cervica1 nerves. Embryologica studies aIso seem to support this concIusion. Therefore, from a cIinica1 point of view as ascertained by the subjective compIaints of the patients, we can IogicaIIy say ‘that the impuIses which produced pain passed through dorsa1 root gangIia which suppIied those dermatomic segments innervated by nerves emerging from between the eighth cervica1 and seventh dorsa1 spina segments. CLINICAL WAY BY

EVIDENCE

OF

CARDIAC

THE

CONCERNING PAIN

NEUROLOGIC (HEAD

AS

THE

PATH-

ASCERTAINED

EXAMINATION

ZONES)

As stated, a11 sensory impuIses which are conveyed by nerve fibers from an organ, must first enter into dorsa1 root ganglia before entering the spina cord to be conveyed by the spinothaIamic tracts to the sensorium. The spinothaIamic fibers transmitting these stimuIi arborize about ceils in the dorsa1 root gangIia known as Dogiel ceIIs. The constant bombardment of these somae by discharges coming from a diseased organ produce in these ceIIs a state of hyperirritabiIity. When a sensitive

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dermatome, which is suppIied by such an irritabIe ceI1, is roused by any physica agent, that is pin prick, heat, cold, painfu1

JULY, ,930

Pectoris

Head zones over the back of the head (C I, II) or over the Iower.jaw (trigemina1 nerve). The investigation aIso failed to

FIG. 2.

response ensues. We thus see that this method of investigation is of great vaIue in ferreting out those gangIia which are the recipients of the continuous stream of painfu1 impuIses from the diseased organ. SimpIy stated, this method reveaIs the pathway aIong which the painfu1 inff uences are traversing so as to enter the spinal cord. Based upon these neurophysioIogic facts, carefuI epicritic and protopathic tests were performed. In the 22 cases observed by the writer, definite sensory changes were observed over the skin. In a11 cases the protopathic skin tests cIearIy gave proof of the hypersensitiveness of the skin. Those zones of hyperirritabiIity were Iimited to areas of the skin suppIied by those periphera1 nerves which emerge from between the eighth cervicaI down to the seventh thoracic spina segments. Again, it is of vaIue to note that the neuroIogica1 examination failed to eIicit

FIG. 3.

revea1 any hypersensitiveness of the skin to these tests over the radial aspect of the upper extremities (C Iv-VII). This method, therefore, also seems IogicaIIy to suggest that the discharges of pain from the heart pass via those sympathetic fibers and dorsa1 root gangIia that are emerging between the eighth cervica1 and seventh dorsa1 (C VIII to D VII) spina segments. OPERATIVE

EVIDENCES

OF CARDIAC THE

PAIN

AS TO THE

AS ASCERTAINED

VARIOUS

PATHWAY FROM

PROCEDURES

In the review of the various operative measures instituted for the amelioration of the severe pain incident to cardiac disease, data were also eIicited which cIearIy indicated what was not the pathway of pain from the heart. Nevertheless, these faiIures in the severa surgica1 attempts to reIieve the pain are of invaluabIe impor-

SwetIow-Angina

New SERIES VOL. IX, No. t

tance in indicating the correct pathways. The various .surgicaI operations wiII be reviewed and discussed briefly, so that a

FIG.

Method

of Danielopolu

American

Journd

of Surgery

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These operators sectioned the cervica1 sympathetic cord on the Ieft side above the steIIate gangIion(Fig. 3). AIong with

FIG. 5.

4.

cIearer understanding may be obtained as to the significance of the information eIicited, thus aiding in the discIosure of the correct pathway for cardiac pain. I. Method of Jonesco. By this method the entire cervica1 chain, aIong with the first thoracic gangIion, was extirpated (Fig. 2). DanieIopoIu objected to this method. He contended that this operation severed the vasomotor fibers to the coronary arteries as we11as the vasoconstrictor fibers to the Iung. These objections were answered by Jonesco in a recent articIe. He asserted that physioIogists, supported by extensive experimentation, are of the opinion that the sympathetics are vasoconstrictors. Hence the removal of the sympathetics does not impair the effkiency of the coronaries but, in fact, augments it. 2.

Pectoris

and Hristide.

this section, the spina gangIia of the spina nerves on the Ieft side were injected with aIcoho1. At that time the operators were not ready as yet to report the value of this method. 3. Method of Danielopolu. (A) On January I, rgzq, this surgeon reported that Gino Pieri of BeIIino was the first to foIIow the operator’s new method. He sectioned the cervica1 sympathetic chain above the steIIate ganghon, together with the vertebra1 nerve, as we11 as a nerve which joins the superior cervical gangIion to the crania1 nerves (Fig. 4). The immediate results were good. No reports as to the condition of the patient at a later date were given. (B) In October, 1924, DanieIopoIu reported resection of the sympathetic cervica1 chain without remova of the inferior cervica1 gangIion and the first thoracic gangIion

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(Fig. 5). In addition he sectioned the vertebra1 nerve and the branches of the vagus, which were about to enter the thorax.

Pectoris

thetics, together with the superior cardiac nerve on the left side. Hoffer in 4 cases of angina pectoris dissected the vagus nerve

FIG. 7.

FIG. 6. (c) In a Iess compIete operation the superior and middle cervica1 gangha were extirpated on one or both sides (Fig. 6). In January, 1925, LiIienthal reported 3 such cases with good results. (D) In February, 1925, the foIIowing operation was performed by DanieIopoIu : the cervica1 sympathetic chain was resected. The inferior cervica1 gangIia, as we11 as the first thoracic ganglia, were Ieft intact. The vertebra1 nerve was sectioned. AI1 branches Ieaving the vagus to enter the thorax were severed. The rami communicantes, which joined the inferior cervica1 gangIion and the first thoracic gangIion to the Iast pair of cervical nerves, were 7). I n addition to these severed (Fig. operations, Eppinger and Hoffer sectioned the so-calIed depressor nerve, whiIe Coffey and Brown severed the cervica1 sympa-

Jury, tqv

without inffuencing the severity of the pain. The resume of these various operations shows quite suggestiveIy that if pain impulses do pass through the middle, superior cervical ganglia and vagus they do so in a very minor degree. These observations are quite supported by the anima1 experimentations to be Iater discussed as we11 as by the resuIts obtained by the paravertebra1 aIcoho1 nerve block. EVIDENCE PAIN

AS TO THE

ELICITED

BY

PATHWAY

MEANS

TEBRAL

OF CARDIAC

OF THE

PARAVER-

BLOCK

This evidence is based upon 22 cases of my own together with 5 cases reported from the Massachusetts Genera1 HospitaI and 16 cases of Mandl’s. In a recent paper from the Massachusetts Genera1 HospitaI 5 additional cases

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were reported in great detaiI in which the aIcoho1 paravertebra1 aIcoho1 bIock was used with admirabIe results. Mandl also reported 16 cases treated by this method with excelIent resuIts. This discussion, therefore, is based on a tota of 43 cases, treated independentIy by three different operators. This method is of invaIuabIe aid in the study of the route taken by these impuIses which incite the perception of cardiac pain, in that we destroy nerve libers and then observe what happens to the compIaint of pain as personahy expressed by those treated. The foIIowing theoretical principIes are of value in understanding the paravertebra1 aIcoho1 bIock as a method in studying the course of cardiac pain. As previousIy stated, the cardiac pain was referred subjectiveIy to the surface of the body supplied by part or a11 of the nerves coming forth from between the eighth cervica1 down to the seventh thoracic nerves (C VIII to D VII, and again, as formerIy set forth, these very same skin segments were the ones which were sensitive to skin tests. The conclusion was quite evident, that if these irritable gangIia or sympathetic fibers which came to the gangIia from the heart loaded with pain impulses, were destroyed, and if pain, as a resuIt of the destruction, disappeared, the pathway of cardiac pain to a great extent wouId be soIved, In light of the fact that an 80 per cent soIution of aIcoho1 destroys myelin and since the afferent sympathetic fibers are lineIy myeIinated, a paravertebra1 alcohol block was performed, injecting each of the irritated ganglia. In al1 of the cases, the paravertebral injections were confined to those ganglia found between the eighth cervica1 and seventh thoracic (C VIII to D VII) spina segments. The analysis of the 43 cases showed that those treated were mostly far advanced patients of heart disease, who suffered because of the persistent agonizing pain, that they all received a paravertebral alcohol injection into some or al1 of the dorsa1 root ganglia and rami communicantes which extended between the eighth cervical

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and seventh dorsa1 (C VIII to D vrr) spina segments, that, except for 5 cases, they were a11 relieved, in various degrees. The resuIts can be briefly summarized as foIIows : I. Twenty-two patients suffering from attack of severe precordia1 pain, were treated by paravertebral injections of alcoho1. Satisfactory reIief was secured in every instance, except 2, i.e., 11 cases gave from 90 to I00 per cent reIief, 7 cases gave from 30 to 85 per cent reIief, and 4 cases were relieved from Iess than 50 per cent to nothing. 2. The aIIeviation of the pain foIIowing a singIe injection has usuaIIy Iasted several months. One patient, who was reinjected after severa months of relief, has again been made comfortabIe for a period of severa months. This freedom from pain is stiI1 enjoyed. Since the cardiac pain was reIieved by the destruction by aIcoho1 of the irritated gangIia found between the eighth cervica1 and seventh thoracic, we can reasonabIy say that the impuIses of pain were intercepted by the aIcohoIic destruction of the nerves before they were able to enter the spinal cord, and since onIy nerves found between the eighth cervical and seventh thoracic were so destroyed, the conclusion naturalIy foIIows, that the pathway of pain is through those rami communicantes and dorsaI-root gangIia found between the eighth and seventh dorsal (C VIII to D VII) spina segments. COMPLICATIONS

AFTER

INJECTIONS

In my own series of cases 3 of the patients compIained of severe pain along the nerves injected. This persisted over a period extending from one to forty days. In some, the pain was sharp and paroxysma1 whiIe in others it was characterized as a dull ache. In ah, however, the pain linaIly disappeared. There is no question in my mind that the pain is due to the chemical irritation of the aIcoho1 inciting an alcoholic neuritis. This is borne out by

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the evidence ehcited by sensory tests over . the skin. In I case there deveIoped a pneumothorax. I am unabIe to expIain this. The suggestion that the needle accidentIy punctured the pIeura and thus produced this compIication does not seem convincing in Iight of the fact that there was no resuIting pIeurisy with effusion. It is aImost inconceivabIe that aIcoho1 couId be introduced into the pIeura1 cavity and no pIeurisy with effusion resuIt. There were no deaths occurring on the operating table or immediateIy thereafter in spite of the fact that desperate cases were particuIarIy chosen for treatment. EVIDENCE

ELICITED

EXPERIMENTATION FOR

BY MEANS

OF ANIMAL

AS TO THE

PATHWAY

CARDIAC

PAIN

In a recent paper by D. Jonescu, experimenta1 observations were made upon dogs and cats as to the course taken by discharges capabIe of producing cardiac pain. His experiments support the same concIusions as were arrived at through our cIinica1 studies upon human beings. The folIowing is a resume of the method used by the experimentor and the interpretation of the resuIts as made by him. The experiment may be divided into four steps. Step I. Upon the pericardium or epicardium being pinched or puIIed, or on the appIication of a I0 per cent soIution of ammonium or barium chIoride to the Ieft ventricIe or on making a simiIar chemica1 appIication to the adventitia of the Ieft coronary artery or aorta, definite manifestations of pain reactions upon the part of the animaIs were seen, that is, marked movements of defence, increased respirations, rise in the bIood pressure. Step 2. The next step of the experiment was to sever on the Ieft side the rami communicantes of the eighth cervica1 and the first thoracic (C VIII to D I) as we11 as the rami communicantes of the thoracic sympathetic chain down to the sixth gangIion. The first thoracic gangIion was not removed so as to permit its continuity

Pectoris with the cervica1 sympathetic chain and the vertebra1 nerve. With this section accomplished, there remained the foIIowing routes for the transmission of pain impuIses from the Ieft heart, the vagus with its depressor branch, the superior cardiac nerve, the cervica1 part of the sympathetic gangIionated chain, the vertebra1 nerve. Again the epicardium and pericardium, the Ieft coronary artery and aorta were stimuIated as was done in Step I and none of the reactions of pain as aIready described appeared in the anima1. However, when the right ventricIe was stimuIated, a dispIay of pain reactions was again eIicited, though mild in nature. No evidences of pain resulted at a11 when the aorta was stimuIated, even though the nerve structures were preserved on the right side. Step 3. The next step was to resect on the right side the rami communicantes, which extended from the eighth cervica1 down to the sixth thoracic (C VIII to D VI). The application of the physica and chemica1 stimuIi to the Ieft or right ventricIe, coronary artery or aorta roused no pain manifestations. This absence of pain is observed even though the vagus nerve, the depressor nerve, the superior cardiac nerve, the vertebra1 nerve and the cervica1 sympathetic chain are Ieft unmoIested. Step 4. In other experiments as carried out in man, the same operator stimuIated the crania1 end of the sympathetic chain but no pain was produced. Additiona evidence was brought by SchittenheIm and Kappis to the effect, that the cervica1 sympathetic chain does not transport pain discharges from the heart and the aorta. They observed an attack of angina pectoris during an operation. They immediateIy injected novocaine into the trunk of the cervica1 sympathetic chain with no reIief ensuing, whiIe upon injecting the steIIate gangIion, there was at once a suppression of the pain. In an earlier paper, D. Jonesco showed that the eIectrica1 stimuIation of the crania1 end of the vagus nerve as we11 as the depressor nerve or vertebra1 nerve, when found in

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man, incited no pain reactions. Hoffer noticed in 4 cases of angina pectoris no influence upon the pain by severing the vagi. D. Jonesco pinched and puIIed upon the vagus nerve without inducing pain evidences in the animals experimented upon. The experiments of Jonesco, together with the work of Hoffer, SchittenheIm and Kappis Iead to the conchrsion, that the impulses of pain pass from the heart through the steIIate ganglion (C VIII and D I) as we11 as those rami communicantes that are found between the eighth cervica1 and sixth thoracic spina segments. SUMMARY

This paper is presented to correIate our previousIy observed cIinica1 findings in patients compIaining of severe cardiac pain with the information obtained by others through animal experimentation. The cIinica1 observations showed, that subjectiveIy, the pain was reIegated to areas of the skin which were suppIied by nerves arising between the eighth cervica1 and seventh thoracic spina segments (C VIII to D VII). These very same skin areas to which the patients subjectiveIy referred the pain showed them to be hypersensitive to protopathic tests (Head zones). These findings indicated that the pain impuIses were passing through the rami communicantes and gangIia, which were to be found between the eighth cervica1 and seventh thoracic spina segments (C VIII to D VII). The indifferent operative resuIts ensuing from procedures upon the cervica1 sympathetic chain and other nerves in the neck indicated by their faiIure to ameIiorate the pain, that the painfu1 charges were not passing through these structures in their course to the sensorium. A review was made of 43

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patients suffering from severe cardiac pain, who were treated by paravertebra1 bIock. The injections were co&red to those rami communicantes found between the eighth cervica1 and seventh (C VIII to D VII) spina segments. The gratifying resuIts obtained seem to quite directIy suggest that these rami communicantes and gangIia are the true conveying pathways of the pain impuIses to the spina cord so as to reach the spinothalamic tracts. In a group of 22 cardiac patients suffering from attacks of severe precordia1 pain, who were treated by paravertebra1 aIcoho1 injections of the dorsa1 root ganglia, prompt and satisfactory reIief from pain was secured in a11 but 4 cases. The freedom from pain folIowing a singIe injection has usuaIly Iasted severa months. In one patient, who was reinjected after four months of reIief, there has been a second period of comfort lasting several months. One case of pneumothorax foIIowed the injection. Five cases deveIoped an aIcoholic neuritis which disappeared from one to forty days. The resume of the anima1 experimentation supports the cIinica1 observations. This showed cIearIy that the imp&es were passing up through those rami communicantes and gangIia found between the eighth cervica1 and sixth thoracic. Such nerves as the depressor nerve and the vertebra1 nerve, rareIy observed in humans, were stimuIated in animaIs and faiIed to incite painfu1 reactions. A perusa1 of a11 the data indicates quite cIearIy, that the future surgical procedures for the relief of cardiac pain must have their attention reIegated to the rami communicantes found between the eighth cervica1 and seventh thoracic spina segments (C VIII to D VII). [For discussion see p. 103.1