PROFESSOR RUTHERFORD.

No. of
Experiment.

No. of
Observation.

NOTICE OF A CASE OF PECULIAR MALFORMATION OF THE HEART AND GREAT ARTERIES. BY A. H. F. CAMERON, M.R.C.S., L.R.C.P.

A MALE infant, which lived for not more than between two and three days after its birth, presented on the first day no peculiarity in appearance, but, on the second day, a very faint purple tinge of the skin was observed, though the warmth of the body seemed to be normal. A post-mortem examination, made unfortunately in a bad light and under other difficulties, revealed a very peculiar and unusual malformation of the heart and great arteries.

The two ventricles freely communicated with each other through a large opening at the base of the interventricular septum. The two auricles formed practically but a single cavity, as the septum was represented by a mere fold. The auriculo-ventricular valves on the right side were feebly developed; on the left normal. From the base of the left ventricle arose the ascending aorta, which passed almost directly upwards in front of the trachea, and terminated by dividing into two branches, the right branch, somewhat the larger, was the arteria innominata, the left might either be a left innominate, or only the left common carotid. The aorta had only two valves at its cardiac orifice.

From the base of the right ventricle arose a much larger vessel, which inclined upwards and to the left, and was prolonged into the descending aorta. From this large artery arose two branches: the one, which bifurcated behind the ascending aorta, was apparently the right pulmonary artery, the other was in all probability the left pulmonary.

I am unable to speak with certainty of the origin of the left subclavian, as the examination was conducted under very disadvantageous circumstances. It is possible that the left branch of the ascending aorta might have been an innominate, in which case the subclavian would have proceeded from it; or the left subclavian may have arisen close to the spot where the great artery from the right ventricle became continuous

with the descending aorta. The two venæ cavæ were normal and there were four pulmonary veins.

Cases of new-born children in which the two sides of the heart have communicated freely with each other, through imperfect formation of the intermediate septa, have so frequently been recorded that I should not have thought of recording this case, had the cardiac malformation not been complicated with the very unusual defect in the development of the great arteries I have just described.

The case on record which presents the closest correspondence to the above, is one described by Dr Greig in the Edinburgh Monthly Journal of Medical Science, July 1852. This case was a foetus about the ninth month. The two ventricles communicated by a large aperture at the base of the septum. The interauricular foramen ovale was normal, and the valve fully formed. The ascending aorta terminated in three equal branches, right subclavian, and right and left common carotid arteries. The pulmonary artery, nearly twice the size of the ascending aorta, gave off its right and left branches to the lungs; a quarter of an inch further on, the artery gave origin to the left subclavian, beyond which, much diminished in size, it was continued on as the descending aorta.

In a memoir on the Irregularities of the Great Arteries, British and Foreign Medico-Chi. Review, July and October, 1862, Professor Turner not only gives an analysis of the cases which had up to that time been recorded, but illustrates their mode of origin by the variations which may occur, either through increased growth or complete atrophy, in the development of the vascular arches and aortic roots in the early embryo. Commenting on Dr Greig's case, Professor Turner offers an explanation, which, as he has kindly pointed out to me, applies equally to the case described in this communication. Atrophy of the fourth left vascular arch had occurred at an early period of embryonic life, in consequence of which the transverse part of the arch of the aorta had disappeared, and the ascending aorta was no longer continuous with the descending thoracic aorta. The blood therefore had to pass to the lower half of the body along that portion of the fifth left vascular arch, which is called the ductus arteriosus, so that the

pulmonary artery and its arterial duct were much larger vessels than the ascending aorta.

It is interesting to note that although the two sides of the heart freely communicated with each other, yet the child during its short life exhibited little or no blue discolouration or diminished temperature.

NOTE ON A PECULIAR ORIGIN OF THE RIGHT SUBCLAVIAN ARTERY. By S. MESSENGER BRADLEY, F.R.C.S., Lecturer on Human and Comparative Anatomy, Royal School of Medicine and Surgery, Manchester.

AMONGST the peculiarities met with in the dissecting-room of the Manchester School of Medicine and Surgery during the Session 1870-71', there was an instance of the right subcla

1 This abnormality existed in the last subject but one which was distributed during the session 1870-71, and it is a curious fact that the next and last subject was affected with a somewhat similar peculiarity. These are the only instances of any peculiarity in the primary branches of the aorta observed in the dissecting-room of the Manchester School for the last five years, during which time I have distributed 120 subjects for dissection. In the second case referred to, both carotid arteries were given off from a short single trunk, and the subclavian arteries arose one behind the other from a point of the aorta further to the left. In this case, as in the one noted above, the right vessel was the more posterior of the two, but did not, as in the former instance, pass between the trachea and œsophagus, but behind them both. Both subjects were females.

There is in the museum of the Manchester School a unique and most remarkable case of abnormality of the aorta itself. The arch is of the ordinary size and in the usual position. The primary branches are given off in the normal manner, with the trifling exception that the left vertebral artery springs directly from the aortic arch. Immediately below the origin of the left subclavian artery, and precisely on a level with the ductus arteriosus, which is rather larger than usual, the aorta suddenly contracts, terminates in fact in a blind pouch; on the inferior aspect of this constriction, and connected with it by continuity of structure, the aorta recommences, so to speak, and almost directly regains its ordinary calibre. There is absolutely no communication between the two portions of aorta which are separated by the constriction, and the appearance may be correctly conveyed to the reader by the similitude of a sausage with a string tightly tied around its middle. Half an inch beyond the commencement of the descending aorta, that is beyond the constriction, the first intercostal arteries are given off; they are as large as average common carotid arteries, and anastomose with branches almost as large as themselves, derived from the internal mammary vessels of either side. All the intercostal arteries are large and tortuous, and they all anastomose very freely with branches of the internal mammaries, but the principal channel of the collateral circulation is the double one which exists between the two first aortic intercostals and the two internal

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MR BRADLEY. ORIGIN OF THE RIGHT SUBCLAVIAN ARTERY.

vian artery being given off directly from the aortic arch. In this case it sprang from the extreme left of the transverse arch on its posterior aspect, and passed upwards and to the right, running between the oesophagus and trachea to continue down the arm in the usual manner. Most of the peculiarities met with in the human aorta and its branches are representatives of the normal condition of the vascular system in other vertebrates. Thus, e.g., cases are recorded of the aorta arching over the root of the right lung, as is the case in the class of Aves: again, all the primary aortic branches have been seen to spring from a single trunk, and such we know is the condition most usually met with amongst the ruminating Ungulata: more frequently, two Brachio-cephalic arteries have been observed to arise from the aortic arch, which is the ordinary mode of division in the vascular system of the Hedgehog, Mole, and Bat. On the other hand, the peculiarity which is here noted does not seem to conform to the normal anatomy of the aorta of any other animal, nor is it explicable by any reference to embryology.

As generally happens where a single striking abnormality is noted, there were many instances of vascular and muscular peculiarities in the subject here referred to. Amongst the most important of them, I noted that the left facial artery terminated in the inferior coronary, while the right was of normal size and arrangement. The left ulnar artery did not form a superficial palmar arch, but, continuing straight along the inner side of the hand, terminated in a single digital branch which was distributed to the ulnar side of the little finger. There was an accessory pudic artery on both sides. There was no posterior tibial artery on the right side, its place being supplied by a large peroneal artery.

A double Pronator Quadratus, which existed on the right side, was the most interesting myological peculiarity.

mammary arteries. Mr Searson, the Curator of the Museum, suggests, as an explanation of this abnormality, that the lower wall of the ductus arteriosus was during embryological development continued quite across the aortic arch, so forming a complete septum between the arch and the descending thoracic aorta.