The Hunterian lectures on malformations of the heart : delivered before the Royal College of Surgeons of England on March 8th, 10th, and 12th, 1909 / by Arthur Keith.

  • Keith, Arthur, Sir, 1866-1955.
Date:
1909
Catalogue details

Licence: In copyright

Credit: The Hunterian lectures on malformations of the heart : delivered before the Royal College of Surgeons of England on March 8th, 10th, and 12th, 1909 / by Arthur Keith. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    occupies a position comparable to the adult stomach, the auricular canal representing the oesophagus and the bulbar part the pyloric end. In Fig. 13 A I have represented what I conceive to be the primitive form of the bulbo-ventricular part of the heart; in Fig. 13 B is shown the atrophy that leads to the aorta being brought into juxtaposition with the mitral orifice ; and in 13 C the changes which lead to the pulmonary artery being brought into contact with that orifice. In the first case the bulbus connected with the aorta atrophies and the part connected with the pulmonary artery undergoes an expansion; in the second case the processes are reversed. The aorta instead of being the dorsal vessel is now the Fig. 13. Showing the atrophy of the primitive cardiac tube which leads to the normal position of the arterial orifices (b) and to the abnormal position (c). a, Primitive ventricle and bulbus cordis viewed on the aspect of their lesser curvature. B, The normal position of the arterial orifices, c, The abnormal position. 1, Aortic orifice; 2, pulmonary orifice ; 3, mitral orifice; 4, tricuspid orifice; 5, body of common ventricle; and 6, bulbus cordis, a'. Right half of bulbus which atrophies in b, the normal fonn; a, left half of bulbus which atrophies in c, the abnormal form. ventral and situated towards the greater instead of towards the lesser curvature (Fig. 13 c). With the atrophy of the lesser curvature of the ventricle and pulmonary part of the bulbus, it is the pulmonary artery in place of the aorta that comes into contact with the auricles. In effect, the origin of the great vessels is reversed as regards the auricular canal (compare 13 B with 13 C). No one has seen an embryo in which the pulmonary part of the bulbus was undergoing a process of atrophy in place of one of expansion, but the assumption is justified by the fact that a complete explana- tion is thereby obtained of the condition seen in hearts with transposed arterial trunks. The theory explains why the aorta is in front of the pulmonary artery and also the reversion in the position of its valves. We see further why the bulbus cordis persists in connexion with the aorta and forms the infundibulum, while the part of the bulbus connected with the pulmonary artery atrophies.