CARDIAC ANEURYSMS. By D. G. Hall, M.A., M.D. (Cantab.), L.RC.P. (Lond.). (Plates VII. and YIIT.) Aneurysms of the heart must necessarily be of interest rather to the pathologist than to the clinician, for they are outside the pale of practical diagnosis, and beyond the reach of treatment; yet even by pathologists the condition has met with but scanty recognition, and will be found in most text-books of pathology and medicine, alike, dismissed in a few lines. There would seem to be no published paper on the subject of later date than AVick- ham Legg's Bradshawe Lecture, in 1883.1 Previous to that, the recognised authority was the essay of Thurnam, published in the Transactions of the Royal Medical and Chirurgical Society for 1888. I have endeavoured to bring the study of the subject up to date, and to sum up and analyse all the cases which have been published in the literature during the twenty years' interval since Legg's paper. The subject of cardiac aneurysms may be treated under three divisions:?(1) Aneurysms of the cardiac walls; (2) aneurysms 1 Med. Times and Gaz., London, 1883, vol. ii. p. 199. 3 23 CARDIAC ANEURYSMS. of the cardiac (c of the cardiac valves; (3) aneurysms arteries. T, i ng& the term Aneurysms of the Cardiac Wal^?I . the heart> aneurysm was loosely used to denote any dila ? ^ restricting local or general, and to Thurnam is due the c heart wall, its use to partial dilatations alone, dilatationsdilafcation as F" rle'nacnehv rwyrsimtee rdse Cstoirlvli sfarretq,u" eanntdly c arredfiearc atnoe ucray sm ?Q ? Van&vrysme vra"i ,I" hoarv "e ,l 'iann aelvl,r ybsemeen paabrltei atlo dceo llect 112 ca ps { ? whtivc-ht wot hcea sseist e; of the aneurysm was as follows: left ventnc , ventricular right ventricle, one case; left auricle, two ?em?ranoua part, septum?(a) muscular part, eight cases, ( ) seven cases; auricular septum, two cases. Vmt baldly Unfortunately, many of the published ^erfca, described, and, in particular, both in this 00u menti0ned, or the the state of the coronary arteries of ^ ?te?'atoromatous," writer contents himself with stating that ti y obstruction, if wainyt.h ouTt haen yv asltuaet eofm etnhte asse tcoa stehse, daesg rreegea rodis aar ceoil lecti. ve iinnVve stigba - tmieonm,Cb lieasr stishniufgsi cgtarhteaiatot nlt.yh? eOdn iehm eiannraittsu hriesad l mley rtehli.y n kas ,b o h_is coi n' nt, elicett iwocanan,rs (j rie0a-fc which have been developed in a special m ciasses like aneurysms might be divided into numerous an and to a arterial aneurysms. This was attempe J wben discussing certain extent can be done, and I shall reie mjw a work of certain special cases, but such a classifica, ion claggi{ication was supererogation and has no real value. ie . rec0rmition of carried out from the point of view ot et gy> jue to pre- the fact that aneurysm of the heart wa is divisions would existing disease; but, in any such of overlap, as I shall point out later when VnArable seems to be the coronary arteries; and the only metlio cFha.mb eis otj the heart that adopted by Legg-to take the four sepaAranteeulyr.y sm of the left ventricle is far n commona tnch\a nfo tr haaltl of the other three chambers of the of the aneurysm practical purposes may be taken as the yp -prellch termin- cardiac walls, or parietal aneurysm, to adopt ology. , yentricle, or in the Its si^ te is most common at the apex larger and older anterior wall immediately above the apex.^ ar?wall Thur- aneurysms naturally involve more of the ven ^ ^ nmaamd,e outth eo fp rsoipxotry-tsiioxn cfaisfetsy,- nfionuen do uttw eonft yn-isneev }e , ^ ' in^ tihee acpaseexs, which I have collected, sixty-seven Thus, in a nineteen were situated in other parts of the 324 D. G. IIALL. total of 243 aneurysms of the left ventricle, 153, or fully three- fifths, were situated at the apex. The condition, as one would naturally expect, is found more frequently in males. In the relative frequency, in the two sexes, Thurnam's, Legg's, and my own figures show a remarkable re- semblance. Of Thurnam's forty cases, thirty were male, ten female; of Legg's eighty-eight cases, sixty-four male, twenty-four female; and of my eighty cases, fifty-nine male, twenty-one female. In a total of 208 cases, 74 per cent, were male, and 26 per cent, female. As regards the occupation of the patients, one lias little to say. In many cases it is unrecorded, but, where stated, I find it very varied, as did Thurnam. My cases include, on the one hand, an old lady of independent means, a manufacturer, a barrister, two clerks, a wine merchant, and a jeweller; and, on the other, a char- woman, a bricklayer, an iron-moulder, a dock labourer, a black- smith, a carter, and two soldiers. The size of these aneurysms is, of course, very variable, and depends to some extent upon the duration of the aneurysm. Sir Samuel Wilks has reported a case where the aneurysm was the size of a cocoanut; and in Thatcher's case, in which there were two aneurysms, one of them is described as being the size of two fists. Many of them may be likened to hens' eggs or Tangerine oranges, and the smaller aneurysms to walnuts, pigeons' eggs, or marbles. Any figures as regards the age of the patient are of very doubt- ful value, for they have no exact significance, merely showing the age at which the subject of the aneurysm died. The aneurysm itself had existed in some cases certainly for years, and in most cases for months, before the death of the patient, and death may be due to an entirely independent affection. Of my sixty-seven cases, forty-one occurred between the ages of 40 and 70, one was under 20, and four were over 80. The solitary case under 20 was due to trauma; 102 out of 177 cases occurred between the years of 40 and 70. These aneurysms are nearly always single?in my series in eighty-three out of ninety-two cases. In eight cases there were two aneurysms, and in one case?that of Kundrat?three distinct aneurysms were present. In three cases the aneurysmal sac was bilocular. One case showed, in addition, an aneurysm of the large flap of the mitral valve, and in one only can I find record of an aortic aneurysm. Cardiac aneurysms only vaguely recall the shape of arterial aneurysms. The aneurysm usually is not visible externally; it forms no tumour; and the heart must be opened to find it, when it appears as a depression hollowed out at the expense of the thick- ness of the heart wall. This depression, in some cases, is not sharply defined, but gradually merges into the healthy wall where the myocardium is of normal thickness. The ventricular cavity '325 CARDIAC ANEURYSMS. may be little changed, merely increased in vo*u^e between the stance in its wall. In other cases the boundary brtwe^ ^ healthy muscle and the seat of the aneui)sn J <( CQ^et? 0f marked off by a raised rim of endocardium diverticulum fr0m French writers. The aneurysm here is like a hcavt wall the ventricle, forming a pouch-like projection g(J that in and changing the external appearance o Tllis second type extreme cases it may resemble an houi-?iass. is more common at the apex (Plate VII. l^S- )? i0^s are Conic,as-In a few aneurysms of the former W and present, but in almost all aneurysms of est duration? these are, broadly speaking, the aneurysms o ? aneurysm the cavity is more or less tilled by blood clot, it is sufficiently shut off from the general ven u wbile the slowly not to be completely emptied during the sy , ^um 0f the moving blood is in contact with the disease ,, with its sac. The clot varies in colour, density and afgier,m ,t haen do ladedrh earenndt dteoe ptehre lhaeyaerrts bweailnl,g a^iX this pVr oceaslisc \ mhaeya,l iingn exceptional cases, go 011 to obliteration ot t le on 0f the of the aneurysm. Nature's attempt at cure, >y o shown in sac by successive layers of laminated clot, is ea^ . fibrinous aneurysm of the left ventricle, and in many ca layeIrsn emayrl yc assheso wo fo argnaenuirsyatsimo no f the apex, tl ppr esence waorg atbhsee nscaec of clot is recorded in forty cases; m one t which empty; in one other there was soft red oo y_eicrht cases might have been formed post-mortem; while fvivnrnlms which tiwnha elml .sa ancy Iw nca asst ewmso ow raceas s oeprsa rlttelshsye foicrllgloaetdn ibcsyoe mdfp ialrnemdt elalaaym nifcniilale ened t^h e^ aq n 1ve^eu ncrtJyrnsitmcru,el asro that the ventricular cavity was functionally ? ., contain- tihneg pculorti fmoramy abnrde aks adnoiowuns aflnudid ,f oarnmd ai ns moladl- sctya nding cases j clot may become calcareous. . almost constant. The pericardium?Pericardial lesions a thickening Sometimes there is merely increased vascular y Uptween the of the visceral layer, hut more often there is adh<"f^ness, two layers. Such adhesion is of variable thickness and close^ and is often accurately limited to the area o 1 other mhaanyd ,b hee seoxftt reamnedl yc eflilruml aar nadn rde siesatsainlty, dseot tahGtaitc ft,h e.t,w o layers n. not hTeh es eepnadraotceadr deixucemp.t? Obtyt ot hEoo ksneinfbea (cIh'l aftoe u\n d t? hat aire i c ],ad artificially damaged the cardiac valves of dogs an . ' 0f the. was very constantly developed an aneurysma 1 1 mitral apappeixl loafr yt hmeu shcelaer.t", anAds aal smoa ta tfeirb roofu s fadcetg,e nheorwae v1e0r1 , few 0f r 326 D. G. HALL. aneurysm of the left ventricle show organic disease of the valves; but, while valve lesions are rare, the endocardium of the aneurysm is invariably altered. On removing the clot, we find that the endocardium has lost its lustre and transparency, has become white and opaque and greatly thickened. At the peri- phery of the aneurysm this appearance passes suddenly or gradually (vide supra) into that of the healthy endocardium. Where clots are adherent, owing to organisation, it may be difficult or impossible to recognise the endocardium at all (Plate VIII. Fig. 2). I shall have more to say concerning pericardial and endocardial changes when I come to consider the etiology of parietal aneurysms. The myocardium.?From the mere presence of an aneurysm it follows that there is some change in the myocardium. Such change may be of the nature of an acute or a chronic myocardial lesion. Acute lesions would include partial ruptures, luemor- rhages, and infarcts. Breschet1 held that all these aneurysms had their origin in a partial rupture of the heart wall, the endocardium giving way and blood being driven amongst the fibres of the myocardium. This, however, is only very exceptionally the case, as will be considered later. Haemorrhages, or cardiac apoplexies, consist in an incomplete rupture of the myocardium, with effusion of blood among the muscular bundles; and they are very frequently the effect of softening of the wall, secondary to obliteration of its nutrient artery. Haemorrhages and infarcts are thus very closely allied. In cases of cardiac infarction the wall of the heart is often thinned, and the endocardium at that site shows a clot, sometimes adherent. On lifting up the clot there appears a dilatation of the ventricular cavity, due to hollowing out of the seat of the infarct. Such is, in my opinion, the beginning of a great number of parietal aneurysms. Fatty degeneration would also come under this heading; as far as the myocardial cell is concerned, it is an acute lesion, usually produced by interference with the blood supply. Broadly speaking, obstruction of the coronary artery at its orifice produces fatty degeneration; obliter- ation or obstruction during the peripheral part of its course produces replacement fibrosis; but the two processes are often very closely allied. Abscesses in the heart wall may be included here, and I have found one reputed case in which aneurysm followed ; but the general tendency of myocardial abscesses is to burst outwards towards the pericardium. The fluid degeneration, which is sometimes met with in the centre of a thrombus, must not be mistaken for an abscess cavity. Chronic myocardial lesions, for all practical purposes, may here be taken to mean fibrosis, which has long been recognised as the great cause of these aneurysms. The wall of the aneurysm is always thinned, and may be so reduced that it is 110 thicker 1 Rejjert. gen. d'anat. et physiol. path., Paris, 1827, tome iii. p. 101. 327 CARDIAC! ANEURYSMS. than brown paper. In most cases wh^e ,^J^by tlie feeling visible as an external bulging, it may jn old-standing of diminished resistance it gives to tlie nn& . calcareous csaalstess, jtuhset afsi brito usd oetsi ssiune otbheecro mpeasrt sn nofp rtehgen ab , y^. dw itthhe waa lsla Wo.f the aneurysm may be so hard that it can 011 y hardness, the Iu other cases, both as regards its thinness ?. Microscopically, wall of the sac maybe compared to an egg-s 10 ? or their there may be no trace whatever of muscu a ^ especially remains may be visible among the connective is ' ^ pr0cess of at the periphery of an aneurysm, one seep my oca arG full of transition, fibres which have lost then' nuc? neCrosis. At ^ pigment or fat granules, or swollen up ) r outline merely ostkehtecrl ipeodi notust tbhye tmhues cfuilbarrou sc eltlh rseeaedms s ofe mp ey ,' y^ i nmabas otrhbee d deo-r generation products referred to above iavn g repiaced removed. Finally, the highly organised hypertrophies and bthyi tchkee nfsi birno usa nt isastute,e mwphti ctho, irfe ptahier ptahtei ednta mage > do>n1e (H^a t^e VIII. gHilton Fagge and Osier regard ^thoiitieV among i. nvariable precursor of aneurysm, but m absolute, them Wickham Legg, hold this assumption found accom- Legg cites three cases where the aneurysm collection, panied by fatty degeneration of the heart. J ^ fatty micro- in four cases the myocardium is said. to q ^e peri- scopically. In all four cases rupture had occi advanced ^ cardium, and in each case mention is ma ^ a inatter aoft hfeacrto,m ian atnhde astneenuorsyiss mosf otfh eth ec oarpoenxa,r tyh ea rftiebnreosus , and >l auy changes have a common origin in coronary obstruction. incontestable; Theories of pathogenesis.?Myocardial errang - , condition, but myocardial disease, fatty or fibrous, is a niyocardium and we must look for the primary cause. ' ^ ^ ^ie myo- is able to resist the intracardiac blood-pressui ' .^Qn t^e blood cardium become diseased, and especially n, m ^ dilatation pressure become increased, the heart wall ma) j' , the myo- local of the heart ensue. Similarly, given ^ loca{ dilatation coar radinuemu rymsamy &yi feoldr maetd .t haTth isspo ti,s iand wmihtitcehd cb y al1,the mdivv erkg en^ce of opinion begins when one looks for the s . resistenti8e," local weakening of the myocardium, the "locus r { tlie three which gives way under the blood pressure; an . seat of layers ot the heart has been held to be the pumaiy diseaPseer.i cardial theory.?Thurnam first insi. ste up ^^h e freqhueeanrtt coexistence of pericardial adhesions and aneury 328 D. G. HALL. wall.1 Pelvet made the same statement,2 though there might be some connection between the two, but knew of nothing to show in proof of the hypothesis. Legg talks of this as " a speculation not likely to find favour with many "; but, in France, Kendu 3 has been a strong champion of this view, which makes pericardial adhesion and aneurysm related to each other as cause and effect. He quotes the case of a jeweller, set. 44, who had had one attack of acute rheumatisn when 24. Death was gradual, and due to heart and kidney failure. Post-mortem, there was, a little above the apex of the left ventricle, an unruptured aneurysm, the size of a hen's egg; it corresponded to the region of a very thick pericardial adhesion, the limits of the aneurysm and the adhesion being exactly the same. The coronary arteries were healthy. Microscopically, in some sections he could see that the myocardial interstitial fibrosis had spread inwards from the pericardium, being merely an extension of the local pericarditis; and he held that in this case the aneurysm was the direct consequence of the pericardial adhesion, the action of which he compared to a sucker. Eendu referred to similar cases, and finally came to the conclusion that some cases of parietal aneurysm very probably originate from circumscribed pericardial adhesion, the fibrous degeneration of the myocardium being only a secondary lesion. Bureau, in 1892, brought forward an exactly similar case in a man of 53, the subject of renal cirrhosis. Clinically, the apex beat retreated during systole (" un battement negatif"). He reviewed all the cases that had been reported to the Socicte Anatomique de Paris since 1880.4 In the great majority the corollaries were reported diseased, but yet in many were largely permeable. Pericarditis, with adhesion over the aneurysm, was more frequent; and Bureau considered that it was the more important etiological factor. I find, in my own collection, forty-nine cases of aneurysm of the left ventricle, in which the state of the pericardium is recorded or was investigated by myself. Of these, thirty-one showed firm, dense adhesion, in most cases confined to the aneurysmal area; six showed loose or slight adhesion over the aneurysm, and twelve showed no adhesion. It is, however, very difficult to imagine that this pericardial adhesion can produce aneurysm. It is surely much more likely to be secondary, caused itself by the irritation of the aneurysm, the adhesion playing an important part in nature's attempt to remedy the defect, strengthening the weakened spot from with- out, as the laminated clot does from within, and tending to pre- vent the aneurysm from bursting into the pericardium. In my collection fifteen of the cases terminated fatally, by rupture into 1 Med.-Chir. Trans., London, 1838, p. 187. 2"Des Aneurysmes du Coeur," Paris, 1867. 3 Gaz. d. hop., Paris, 1887, p. 1318. 4 Bull. Soc. anat. do Paris, 1892, p. 738. 329 CARDIAC ANEURYSMS. the pericardial cavity; m only one of tbese t is it noted that there was pericardial adhesuo,b^l that case the aneurysm ruptured "at its upper part, 1 beyond the area of adhesion. This hypothesis m no exT)lains the J'^esc thickening of the endocardium, or the tact c parietal aneurysms are almost confined to the left, qi0ne and in veu^ the great majority of cases are found near ui I * ? Moreover, while in pericarditis there is usually some ex ens on to ^t myocardium, it is only to the upper and middle.layers^ there are numerous post-mortem examina1bionsi w ^ cumscribed pericardial adhesions with little myocardial fibrosis, far less aneurysm. In some eases of ane?y?utUh^eroe is no pericardia) adhesion at al), and m others to obviously of a later date than the aneurysm. ^ although the aneurysm was of such an age that bott.^J? ^ and contained dot were catareous, the pericarde loose and easily separated. The pericardial theoij seem wholly untenable as an explanation of the oiigin q{ the left ventricle. The endocardial theory.?Breschet t, aug , 1 , .i,n4- nii these aneurysms were "false"?that there was m eveiy i rupture of the endocardium?but this view lias long ago ,an^one(j Such would be cases where the cause of thes aneuy^ wag partial rupture of the heart from within. Ihese aneury8m8 cannot be put out of account altogethei (){ infinite rarity; for the blood, once the rUptured, is driven among and destroys the muscular fib raTndly causes perforation into the pericardium. Gouget an x ^ave each reported a case of interstitial aneurysm 01 ti ventricle, the endocardium lying between the clot ancl i of fche ventricle. Co/nil considered that in both cases the aanneeumryy sm had been formed by a rupture of the endocardinm, wtucn afterwards healed up. Vestberg has made an ^ dissecting aneurysm of tl1? heart, which he denncs a^s ? ^a pat ll0. logical cavity communicating with the he ^ origin of the aorta, due to a separation by the b the layers, of tissue composing the wall of the heart. Many fatal cases of rheumatic fever show acn e mvocarditis; and parietal endocarditis, with extension o process to the underlying myocardium, has een 1V0USht forward as a cause of aneurysm. In most cases of c iron -i my0car- ditis, even where the whole thickness of the leai involved, internal to a narrow band of muscular fibres usually remain j the myocardium,2 which negatives extension o ' cn(jocarc\itis while being the cause of the myocardial ^ ls valvular endocarditis is common, parietal pr0. 1 Scmainc vied., Paris, 1898, P- 43- 2 Brarmvell, " Diseases of the Heart, ti 1884, p. rgg 330 ' D. G. HALL. portionately very rare; and, as regards tlie aneurysms of the apex, this view may be quite put out of court. In the minority of aneurysms of the left ventricle, those situated at the base, such a process might give rise to aneurysmal formation, especially if there were superadded an increase of the blood pressure from, say, renal cirrhosis. Thrombi are sometimes found in the cavities of dilated hearts, lying against the endocardium, where there is a tendency to quiescence of the blood currents, as in the apices of the ventricles, behind the columnae carnese, and in the auricular appendices. There is no evidence to connect these thrombi with the formation of aneurysms ; they are usually multiple, and are more common in the right side of the heart. The myocardial theory.?Myocardial fibrosis is admittedly the great cause of these aneurysms, but we must remember that it itself is only a secondary condition. Sansom,1 on aneurysm of the heart, says: " Syphilis is not the only determining cause, but it is probably the most frequent," while Yirchow held syphilis to be the great cause of interstitial myocarditis. Be that as it may, and I, personally, can find but little evidence to connect syphilis and parietal aneurysm of the heart, syphilis acts in this manner owing to the endarteritis of the coronary arteries which it pro- duces, the cellular proliferation always beginning in the tissue surrounding the ramifications of the vessels; and it is to coronary obstruction that I give the chief part in the causation of aneurysm of the left ventricle. Pelvet first of all tried to make out a connection between coronary obstruction and cardiac aneurysm. Cohnheim pointed out that interstitial myocarditis might be a sequel of plugging up the coronary arteries. This was strongly supported by Huber, who, in twenty cases of sudden death from heart failure, studied with care the alterations of the coronary arteries and the myocardium. He regarded the layers of fibrous tissue among the myocardium as simply layers of cicatricial tissue, sometimes well limited and having the appearance of an infarct, and sometime diffuse and of irregular contour. The former were due to sudden obliteration of the vessel; in the latter set of cases the obliteration had been slow. To the appearance produced when the coronary obstruction was sudden, Ziegler gave the name "myomalacia cordis," by which it is now usually known. Two years after Huber's paper Leyden distinguished four sets of cases, namely, the two described by Huber, and, in addition, mixed cases which showed fibrous layers with portions of recent hemorrhagic softening; while he also pointed out that there might be coronary disease without alteration of the heart, when, although the arteries were diseased, there was no obstacle to the circulation. Weigert, in a paper on tissue coagulation, showed how intimately related were changes in the coronary arteries and fibroid lesions 1 "Diseases of the Heart," 1892, p. 44. CARDIAC ANEURYSMS.' 331 of the myocardium, in tlie sense of cause and e^ec^ obstruction causing fibrosis; sudden obstruction, coag crosis. Sir Kiclmrd Douglas Powell strongly coronary obstruction causcs myocardial fibrosis, w 11c 8 or local according to the seat of the obstruction. e "corresponding with well-marked patches or 'scais ; in , hpirt's substance, there will often be found a complete o . a coronary branchlet from thrombosis or embolism. Wickham against this viLeewg,g , cownhsoid esreeedm st hatto ihna vHeu bbeeresn craastehse r plvireohji^doieeead disease the patiecnotusl, da nbde tahmapt liyt waacsc o?u fnatre dm ofrore blyik etlhye tah atv at he a^vte oarosm 0af follows the age of the patient, and is '*bron dl^eratton" scarring, than that the atheroma causes the Cohnheim had based his embolic theory o sidered an anatomical fact, namely, that the coionaiy were "end-arteries," or at least their that embolic or thrombotic obliteration of a ran tBioownl boyf, tahned airnedae pseunpdpelnietdl.y bEyx pSearmiumeeln tWse sma de? by^t ^ anC\ coronary arteries anastomosed freely by branc , 1 ven_ tricles and apex. The extensive researches of Lindsay gteven at a later date tended to support the older view, c ^ ^ anastomosis AColaetxsa,n daeftre rM woearxsia smboiynn iffniongue n Sadrt tetevhreein e'rss e sasunpldet coicfam pehinilssl, am rwijeaes > y> ^- e^ those of Legg and West. The great cause of obstruction to the roronarv circulation is admittedly not embolism, but thrombosis Jfhproma ? and the results of these experiments must be ^ discounted, in mfiygu reosp igniivoen,n bbeyl owt,h et hfaatc ti,t iwsh niocth wiist h ctlheaer a>n . ? i1 iiBhed Wbeya ltthhye arteries that we have to deal when studying; an y ^ie ventricle, but of atheromatous vessels ^ anastomos. nig branches?if we assume such exist themselves diseased, as these photographs show. The, ,, t the above- conthe S^sZtrShc different pres- Slflns^y leen have made. 1 can offer no other solution. of I find the state of the coronary arteri. es m^^3int fifhtv-yone my cases. Of these, in five, the arteries.arew/s stlhirgohutg ahtohuetr;o imna o; nei,n tthweerlev ew,a tsh e" rneo \oyabss terxufccetJilosln^ , ' wjthout aofn yt hmee ndteisocne nodf icnogm pilnettere- voebnlittreircautliaorn ;b rman tcwh ofE> ttuhreee ' 'thc^eo r^lounrmaeryny artery was completely blocked; in two, the ng was completely blocked; and in four, both coron1 Series were blocked in some portion of their course. In eveJi y case wliere