Congenital Anomalies of the Heart 41 



Following are cases of single atrio-ventricular opening: 



Martin (1826), Mauran (1827), Thore (1842) (1843), Vernon (1856), 

 Martin (1877), Jacoby (1884), Chapatot (1889), Reifschlager (1897), 

 Turner (1891), Grothe (1898), Grosse (1903), Schreiber (1903), Wright 

 & Drake (1903), Cohn (1904), Lefas (1904), Rogers (1905), Kiihne 

 (1906), Paterson (1908), Keith (1912). 



§ XV. 



X. IRREGULARITIES IN DEVELOPMENT OF THE 

 DUCTUS ARTERIOSUS 



This structure is a part of the arterial system and is only con- 

 sidered with cardiac anomalies on physiological grounds. Our 

 interest is principally in persistent patency which is the only 

 condition which will be presented here. 



The first case of persistent duct was probably not described by 

 Botallenus, after whom it has been called, but by Galenus, who 

 seemed to know of the changes which occur after birth. Fallo- 

 pius and Cardanus both knew of the duct and that it could 

 remain open after birth. The function seems to have been well 

 described by Harvey in his Motu Cordis en Sanguinis (1648). 



The factors which prevent the normal obliteration are no better 

 understood than those which cause the right aortic arch to per- 

 sist in certain cases, or, indeed, bring about any other develop- 

 mental irregularity ; a number of theories have been advanced 

 which it is not profitable to discuss here. 



Persistent patency may occur as an isolated lesion or, more 

 frequently, in conjunction with other congenital cardiac anoma- 

 lies. In the isolated lesions Goodman (1910) found that females 

 are affected more frequently than males in the ratio of 20:11. 

 The oldest case was 53 ; death could not be attributed to the open 

 duct, although 7 were persistently cyanotic and 16 suffered from 

 dyspnoea. There seems to be no pathognomonic sign or symp- 

 tom, yet from the symptom complex a clinical diagnosis may be 

 made. A full review of the clinical diagnosis has been made by 

 Wells (1908). Vierordt thought that the condition of isolated 

 frequency constituted about 4 per cent, of all congenital cardiac 

 disease but Wells thinks the frequency is much greater. The 



