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1494 HARVEIAN SOCIETY OF LONDON. which necessitated the removal of the greater part of that bone. In both cases an excellent result had been obtained with little impairment of the use of the limb. If, therefore, it was found desirable to remove that bone to obtain free access to the artery it might be done without hesitation.-Mr. ALLINGHAM, in reply, said that he had I freely divided the sterno-mastoid an inch above the clavicle, exposing the inner border of the scalenus anticus where the artery was found pulsating and ligature could readily be passed round it. He had used kangaroo tendon for the first operation in deference to the advice of his colleagues, but at the second he employed sterilised silk which was the ligature which he habitually employed. Before operating he had considered the question of removing the clavicle but was unable then to obtain any information on the subject. Subsequently the annual general meeting was held. The report of the Council showed that the financial position was satisfactory and that there had been very large attendances at the meetings, especially at those devoted to demonstration of living cases. Hearty votes of thanks were given to the retiring President, Mr. Langton, the retiring honorary secretary, Dr. Kingston Fowler, and other officers. The following gentlemen were elected to hold office during the session 1899-1900 :-President : Sir Richard Douglas Powell, Bart., M.D. Lond. Vice-Presidents: Dr. Sidney Coupland, Dr. James Frederic Goodhart, Dr. Leonard William Sedgwick, Mr. A. Pearce Gould, Mr. John Hammond Morgan, and Mr. Herbert W. Page. Treasurer: Mr. F. Howard Marsh. Council: Dr. Arthur T. Davies, Dr. J. Kingston Fowler, Dr. Archibald E. Garrod, Dr. W. Julius Mickle, Dr. J. A. Ormerod, Dr. J. F. Payne, Dr. J. J. Pringle, Dr. H. D. Rolleston, Dr. Harrington Sainsbury, Dr. R. Percy Smith, Dr. J. C. Uhthoff, Mr. W. H. Battle, Mr. James Berry, Mr. Stanley Boyd, Mr. L. A. Dunn, Mr. F. S. Eve, Mr. Stephen Paget, Mr. G. H. Makins, Mr. T. Pridgin Teale, and Mr. G. R. Turner. Honorary secretaries : Mr. Charters J. Symonds and Dr. Percy Kidd. HARVEIAN SOCIETY OF LONDON. The Etiology and Significance of Dilated Beart.- Exhibition of Mic’l’oscopÙJ Specimens. A MEETING of this society was held on May 18th, Mr. H. E. JULER being in the chair. Dr. H. A. CALEY read a paper on Considerations as to the Etiology and Significance of Dilated Heart, which is published at p. 1483 of our present issue. Dr. ALEXANDER MORISOX considered that the simplest method of regarding the etiological factors in the production of cardiac dilatation was to remember the essential triunity of the so-called functional unit and to refrain from dis- sociating the muscular, hagmic, and neural elements of which it was composed. He protested against the tendency of many physiologists at the present day to regard the muscular element as the predominant factor in sustained rhythmical action, and considered that both clinical experience and pathological investigation, rudimentary though the latter still was, pointed to the important rôle played by the nervous system in such cases. Dr. JOHN BROADBENT said that the question as to what were the factors which determined the relative amount of dilatation and hypertrophy after endocarditis was one of great importance. He considered that the myocarditis which so frequently accompanied endocarditis and not the actual lesion of the valves was responsible for the initial dilatation from which the heart might entirely or only partially recover. Subsequently, as the valves in the process of repair became puckered and deformed by cicatricial contraction of the granulation tissue on their surface the effects of the valvular lesion became pronounced and led to fresh dilatation of the heart followed by hypertrophy which constituted a measure for estimating the extent of the valvular lesion. It was important, therefore, not only to enjoin absolute rest after an attack when the heart was recovering from the initial dilatation due to accompanying myocarditis, but subsequently to insist on great care and moderation in exercise at a later period when compensatory changes called forth by the valvular lesion were taking place. Otherwise undue and permanent dilatation with excessive hypertrophy might ensue. Dr. G. A. SUTHERLAND asked whether dilatation was ever present without hypertrophy. Dilatation must be either an active or a passive process as regards the cardiac muscle. A passive dilatation in cardiac failure implied that the blood could be pumped through the arterial and venous systems by the left ventricle in a weakened condition and yet remain under sufficient pressure to dilate the ventricle. It was diflicult to accept such an explanation on physical grounds, as venous engorgement and cardiac syncope would appeap- to be a more likely result. Active dilatation, on the other hand, might be the calling into play of some reserve power in the heart which by greater expansion and more rapid action was enabled to carry on the circulation. As compensa- tion was often fully established under these conditions he thought that dilatation might be looked upon as a consereap tive process and one not necessarily to be interfered witb medicinally or otherwise, although it was recognised that. over-action of the heart was present and that a breakdown must occur in the course of time. Dr. POYNTON agreed with Dr. Sutherland as to the difficulty in many cases of explaining dilatation of the heart upon mechanical considerations. In rheumatism dilatation might be very marked and the clinical symptoms compara- tively slight, whereas in other conditions the clinical symptoms might be very severe and the dilatation slight. Microscopic examination of the heart walls sometimes showed extensive myocardial disease with little dilatation and sometimes the reverse. In rheumatism he thought it. probable (a view also held by Dr. Lees) that the marked dilatation was explained by a special and peculiar action of the rheumatic toxin upon the cardiac muscle. The difficulty and complexity of these questions of cardiac dilatation were illustrated by the case of a young man, aged about 24 years, who having been I out of sorts " for some days went for the first row of the season in a " four oar " to "shake it off." On landing after this exertion he vomited and later in the day was seen by a medical man who found that his heart was. extremely rapid, the pulse-rate being about 200 to the minute. He was admitted under the care of Dr. Cheadle to St. Mary’s Hospital in this condition and he died two or three days afterwards, the heart acting to the end at this extraordinary rate. The post-mortem examination showed some mitral valvulitis and old pericarditis, but the dilatation was quite moderate. In this case there were two factors-a damaged heart and the mechanical strain, both, one would have thought, tending to produce great dilatation rather than a condition of tachycardia with little dilatation. He thought it was important to get a definite idea of the meaning of fibrous changes in the heart wall. Sometimes they were brought forward to account for dilatation and sometimes they were given as an explanation of its absence. These fibrous changes which arose in connexion with the vessels were essentially reparative, he thought, and an evidence of nature’s reaction, however imperfect, to morbid processes. The valve deformities in rheumatism were thus an evidence of reaction to the toxic process rather than an evidence of the active effects of the toxaemia. Dr. BEZLY THORNE was glad to find so much importance attached to the first stages of dilatation, because by their early recognition and relief the physiological call for hyper- trophy and the ultimate sequelae of degeneration and loss of compensation could in a large number of cases be obviated. With regard to tobacco poisoning the practice of inhalation was the most certain and rapid in evil effect. Abnorma} sexual excesses were the cause of cardiac dilatation in other cases and some of these were the most obstinate. He addeël that myocardial and vascular degenerations which had not proceeded to calcification, and especially those which were attributable to atheroma and fatty degeneration, were among the most amenable to treatment of cardio-vascular affections. The free ingestion of water, at such times as not to interfere with gastric digestion, by promoting elimination of toxins was an effectual means of reducing vascular tension in cases in which sclerotic changes had not rendered increase of arterial lumen impossible, not excepting cases of commencing dilatation of the aorta. Dr. H. A. CALEY, in reply, remarked that practically they could only estimate alterations in the cardiac nervous mechanism by noting any alteration in the frequency and rhythm of the heart-beat and by estimating as far as possible the amount of contractile vigour which the heart muscle possessed. In reply to the question as to whether slight degrees of dilatation might not be beneficial he pointed out that just as a slight degree of dilatation under physiological conditions might be a mechanical advantage., so a corresponding degree of dilatation under pathological
