Naidu, Claudia

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South Africa~ Medical JournalSuid..Afrikaanse Tydskrif vir GeneeskundeVAN DIE REDAKSIEHARTVERLAMMINGL. N. Katz 1 het onlangs 'n lesing aan die Kollege vanGeneeshere van Philadelphia gegee wat gegaan het oordie meganisme van hartverlamming op grondslag vandie opvattings van sy ,skool' wat die probleem viramper 25 jaar al bestudeer het. Hy versmaai ,therecent trend of semantics in which the terms congestivefailure, low-output failure, and high-output failurehave come into vogue'. Hy is van mening dat hierdieuitdrukkings tot 'n mate van misverstand gelei het;,Iow-output failure' mag aan baie faktore te wyte weesen die hart hoef in die eerste instansie riie noodwendigdaarmee betrokke te wees nie, en, ,high-output failure'is 'n verkeerde benaming. Hy beskou ,congestivefailure' ook as 'n verkeerde benaming aangesien kon-gestie kan plaasvind of die hartbloedsomloop afneemof nie en dit kan ook voorkom in ongesteldhede van. diebloedvatstelsel wanneer daar met die hart niks ver-keerd is nie.Hy versuim ook nie om die losse gedagtegang i.v.m.die begrip van sogenoemde regter- en linkerhartver-lamming te korrigeer ni-e. In dinamiese ewewig pompdie regter- en linkerhartkamers dieselfde hoeveelheidbloed; slegs wanneer 'n pasient se bloedsomloop beginverswak, of hy van die verswakking herstel, of as hysterwend is, is daar wat 'n geringe volume betref enigeonewewigtigheid hoegenaamd, maar daar is geen on-gelykheid in die hoeveelheid wat die twee kante van diehart uitstoot nie. Ondoeltreffendheid volg wanneer diehart onbekwaam is om sy werk te doeri. Somtyds leidit tot die staking van die hartbloedsomloop (afgesienvan ekstrahartbloedsomloopstaking) en somtyds totkongestie.Inspanning van die hart mag die gevolg wees van 'ntoename in die bloed wat deur die are terugvloei, 'ntoename in die groot- of longslagaarbloeddruk, of vansekere ander laste wat nie so maklik verklaar kan wordnie. Die meganismes wat betrokke is by die oorkomingvan die verhoogde lading is (a) die eenvoudige me-ganisme van uitsetting; (b) die toename in die spier-massa, deur hipertrofie, wat tyd neem; (c) hartversnel-ling, as gevolg van verminderde cholinergiese en ver-hoogde adrenergiese invloed; (d). verhoogde saam-trekkingskrag van die hartspiere wat deur hormoon-en refleksmeganismes teweeggebring word.Hierdie is die 4 kompensasie-meganismes waarmee14 Mei 19554EDITORIALCARDIAC FAILUREIn a recent lecture to the College of Physicians of Phila-delphia the mechanism ofcardiac failure was presented byL. N. Katz 1 based on the concepts of his 'school'which has been studying the problem for nearly 25years. He scorns 'the recent trend of semantics inwhich the terms .congestive failure, low-ou!put failure,and high-output failure have come into vogue'. Hefeels these terms have led to some confusion; low-outputfailure may be due to many factors and need not beprimarily cardiac, while high-output failure is amisnomer. He regar9s congestive failure also as amisnomer, as congestion may occur whether there iscardiac circulatory failure or not, and it may also occurin disorders of the vascular system when the heart iscompetent.He does not omit to correct the loose thinking asso-ciated with the concept of so-called right and left heartfailure. In dynamic equilibrium the right and leftventricles pump out equal quantities of blood; only whena patient is going into circulatory failure or recoveringfrom it, or is moribund, is there any disequilibrium as faras minute volume is concerned, but there is no disparityin output of the two sides of the heart. Heart failurearises from incompetency of the heart. Sometimes thisleads to cardiac circulatory failure (as distinct fromextracardiac circulatory failure); and sometimes thisleads to congestion.Stress upon the heart may be due to an increase inthe venous return, to an increase in the systemic orpulmonary arterial blood pressure, or to certain otherloads not so easily demonstrated. The mechanisms thatare involved for overcoming the increased load are (a)the simple mechanism of dilatation; (b) increase of themass of muscle, by hypertrophy, which takes time;(c) tachycardia, through reduced cholinergic andincreased adrenergic influence; (d) an increase in thecontractile power of the myocardium brought about byhormonal and reflexogenic mechanisms.These are the four compensatory mechanisms by459460 S.A. MEDICAL JOURNAL 14 May ~955die bart sy spannings oorkom en wanneer hul almalsaam in werking is, is bul onderling afhanklik. Opgrond van hierdie opvattings is dit ook moontlik omhartreserwe in terme van uitsetting, oorvergrcHing,hartsnelheid en saamtrekking tl(.. definieer, alhoewel ditnie altyd moontlik is om hierdie 4 hartreserwemaatreelsduidelik te definieer nie. Daar is egter iets te se virdie begrip dat daar 'n perk vir elkeen van hierdie maat-reels is waarbo verdere toename nie moontlik is nie,of indien moontlik, nadelig. Die aanpassings, wat vir'n stygende lading op die hart vergoed, is beperk. 'nStadium word bereik wanneer die meganismes on-voldoende is en 'n nuwe reeks gebeurtenisse vloei voortwat ingewikkeld is; baie dele van die bloedsomloopraak betrokke in 'n wisselwerking ·tussen menige vloei-stof- en neurogeniese beheermeganismes.'n Ander aspek van hartverlamming wat deur Katzbehandel is, is die meganisme V~lll hartedeem. Sygevolgtrekkings oor die kwessie van edeemvorming inkongestie is dat dit nie stuwing in enige besondere deelvan die liggaam is of buislose klierstowwe wat dieabnormale natriumchloried- en vloeistofwerking vandie nier veroorsaak nie maar stuwing per se. Die aar-drukverhoging bewerkstellig op een of ander manier'n meganisme wat die nier natriumchloried en waterlaat terughou. Edeem by hartverswakking word deurdie hart veroorsaak maar ongesteldbeid van nier-(buis)werking is die gevolg van 'n receptor-effector-meganisme. Faal die hart dan reageer die liggaam asofnatrium ontbreek terwyl dit in werklikheid met natrium-chloried en water oorlaai is. Die mening is dat ditdie herabsorpsie van hierdie stowwe is wat geraakword, maar Katz gee aan die hand dat daar inmengingis met die werklike afskeiding van natriumchloried ofwater uit die bloed uit na die nierbuise.1. Katz, L. . (1954): Trans. Coil. Pbys. Philad., 22, 53.which the heart meets its stresses, and when all operatetogether they are interdependent. From these conceptstoo it is possible to define cardiac reserve in terms ofdilatation, hypertrophy, heart rate, and contractilepower, although it is not always possible to define thesefour measures of cardiac reserve clearly. There is,however, merit in the concept of an upper limit for eachof these measures beyond which further increase isimpossible or, if possible, becomes detrimental. Theadjustments which compensate for an increasing loadon the heart are limited. A point is reached where themechanisms become inadequate and a new series ofevents ensue which are complex; many parts of thecirculation become involved with an interplay of manyhumoral and neurogenic regulatory mechanisms.Another aspect of heart failure considered by Katzis the mechanism of cardiac oedema. His conclusionson the question of oedema formation in congestion isthat it is not stasis in any special part of the body orendocrine substances which cause sodium-chloride andwater dysfunction of the kidney but stasis per se. Risein venous pressure somehow sets up a mechanism thatcauses the kidney to retain sodium chloride and water.Oedema in heart failure is caused by the heart, butderangement of kjdney (tubule) function is producedthrough a receptor-effector mechanism. In heartfailure the body reacts as though it were depleted ofsodium whereas actually it is overloaded with sodiumchloride and water. I t is believed that it is re-absorptionof these substances that is affected, but Katz suggeststhere may be interference with actual secretion of sodiumchloride or water out of the blood into the tubules.1. Katz, L. N. (1954): Trans. Cotl. Phys. Philad., 22,53.CHEMISTRY OF MINDThe· physiological background of thinking and feelinghas long been a problem and a challenge to researchworkers. With recent advances in biochemical knowledgesome progress in being made in this difficult field. In1954 Woolley and Shawl described the properties of asubstance called serotonin (S-hydroxytryptamine) whichis normally present in mammalian sera. rts main actionsare twofold-it is a vasoconstrictor by virtue of itseffect on smooth muscle and it also appears to be ofimportance in neural function. Large amounts ofserotonin are found in brain, peripheral nerve andvisceral ganglja. In an attempt to discover its precisefunction in cerebral metabolism attention was directedto a group of substances which are so closely relatedchemically to serotonin that they 'block its action onthe brain. Some of these substances such as the ergotalkaloids, harmine etc. have been known for centuriesto produce a transient abnormal mental state charac-terized by visual hallucinations, change in affect, feelingsof unreality etc. in a setting of clear consciousness.Woolley and Shaw suggested that a deficiency ofserotonin might be the cause of the spontaneouslyoccurring psychosis, schizophrema, because the 'experi-mental psychoses' resemble it so closely.Another group of workers (Hoffer, Osmond andSmythiesF were also interested in the experimentalpsychoses. Their starting point was that mescaline,which is well known for the extraordinary mentalabnormalities it produces, has a chemical structuresimilar to adrenaline. If tfi.ey could find a 'midway'substance with the physiological effects of adrenalineand the psychological effects of mescaline they mightfind the answer to schizophrenia. They systematicallytested substances chemically similar to mescaline andfound a small number that caused psychological distur-bances. They were all plant alkaloids-ibogaine (froman African bean), lysergic acid (from rye rust), hashish(from Indian hemp) and a fungus Amanita pantherina.Then by chance they found that a degradation productof adrenaline---called adrenochrome because of itspink colour-had a similar chemical structure to theseplant alkaloids, could produce identical psychologicaldisturbances, and could occur in the human body.They tentatively suggested that adrenochrome might beAN ANALYSIS OF 519 CASES OF DIPHTHERIA IN JOHANNESBURG 1951-1952V. BOKKENHEUSER, CN~. MED. (COPE1\TH.), DIPL. BACT. AND SERO. (PARIS)South African Institutefor Medical Research, JohannesburgS . A . T Y D-S K R I F V I R G E NEE S K U N D E 461DIAGNOSISAs early treatment of diphtheria is decisive in obtainingfavourable results, it must once again be emphasizedthat the primary diagnosis in this disease is entirelyclinical. If there are adequate clinical reasons for .takinga swab for C. diphtheriae (KLB) the immediate use ofIt may be that adrenochrome and the plant alkaloidsof the mescaline group all work by acting as antagoniststo serotonin, but whether there is this link betweenserotonin and adrenochrome has not been established.What does emerge from these interesting and stimulatingexperiments is the fundamental importance to· progressin psychiatry of basic medical research.1. Woolley, D. W. and Shaw, E. (1954): Brit. Med. J., 2, 122.2. HolIer, A., Osmond, H. and Smythies, J. (1954): J. Ment.Sci., 100, 29.3. Sandison, R. A. (1954): Ibid., 100, 508.of immunized to non-immunized was the same as inEngland 2 and Copenhagen. 3 Murray 4 showed in 1942that the mitis type was responsible for 85 %of the casesin Johannesburg, and since no change has been foundon later periodical surveys,5 it can be assumed that thelow complication rate is due to the mitis infection.The cases that recovered completely amounted to88 %; 4 % were discharged with residual defects, suchas abnormal heart function (ECG), persistent palatalparalysis or peripheral neuritis, all of which are com-plications with a good prognosis if they occur late inthe disease.6, 3The case mortality was 7·7 %, which is the highestreported in Johannesburg in the last decade.1 Thissuggests, if the distribution of bacterial types .hasremained unchanged, that antibiotics, especially penicillinand sulpha drugs, which have been used extensively,are without influence in preventing death.From these figures it is obvious that diphtheria inSouth Africa should not be considered as a disease ofthe past, but as a problem of current interest. On theother hand it is well known that a number of factors mayinfluence or moderate the outcome of the disease. Thesewill be analysed in this article and an attempt will bemade to evaluate each one.The age distribution of the 519 patients was similar tothat found in a previous survey,! 50% being under7 years and 75 %under 12. The patients who had beenactively immunized prior to admission were about2 years older than the non-immunized, e.g. 50 % of theimmunized were under 7-8 years, whilst 50% of thenon-immunized were under 6.the answer to schizophrenia, and by injecting themselvesintravenously with adrenochrome they produced transientabnormalities of thinking and feeling which they claimare indistinguishable from those observed in schizophre-nia.One of the mescaline-related plant alkaloids-lysergicacid-is already being used therapeutically by somepsychiatrists (Sandison 3). They say that it can be ofgreat use in neurotic patients because minute doses bymouth produce a transient psychosis in which thepatients' unconscious fantasies and memorie.s 'erupt'into consciousness, providing valuable informationfor analysis.14 Mei 1955No. ofPatients %Complications:Bullneck 93 18Tracheotomy 27 5Toxaemia .. 26 5Myocarditis 94 18Palatal Paralysis 36 7Other Neurological Complications 30 6Nephritis .. 26 5Total with Complications 173 33 ·5Recoveries:Complete .. .. .. 456' . 88Discharged with Residual Defect 23 4Deaths 40 7·7TABLE I. CLTh'lCAL FEATURES OF 519 EUROPEA CASES OF DIPHTHERIAIt has recently been shown that diphtheria in SouthAfrica is still a serious and widespread disease,responsible for 200-400 deaths annually.1 It was thereforeconsidered worth while surveying the clinical aspectsof the disease, particularly with reference to the therapy.The survey wa's carried out on 519 consecutive Euro-pean patients admitted to a Johannesburg hospital duringthe 2 years 1951-52 and treated as diphtheria. A clinicalanalysis of the cases is presented in Table 1.Bullneck and myocarditis were the commonest com-plications in this series (each accounting for 18 %),whilst the- remainder each occurred in 5-7 % of thecases. Tracheotomy is included as a complicationalthough it is a form of therapy of a mechanical obstruc-tion. The complication rate for the total material was33 ,5%, which is rather low. 3, 17, 18 This might be dueto early treatment, to a high proportion of immunizedpatients, or to a predominance of the mitis strain ofCorynebacterium diphtheriae. There is hardly anyreason to assume that patients are admitted to hospitalearlier in Johannesburg than elsewhere. The proportion

Van die redaksie: Hartverlamming

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Van die redaksie: Hartverlamming

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