Congenital Anomalies of the Heart 5 



wait till we have a better understanding of the reaction of em- 

 bryonal tissues to inflammatory processes. 



Rheumatism, tuberculosis and syphilis have all been studied as 

 possible etiological factors but there is no positive evidence that 

 they act even in an indirect way. 



Frequency. — As early as 1814 Gintrac suggested that cardiac 

 defects were more frequently to be found in Great Britain than 

 in France and Germany and that they were quite rare in Italy 

 and Holland. This observation seems to be true at the present 

 time with the United States occupying a place of slightly greater 

 frequency than Italy and Holland. 



It is very difficult tO' secure statistics which will throw light on 

 the relative frequency, for without postmortem examination very 

 few cases can be positively identified as congenital defects and 

 many cases present no symptoms calling attention to the heart 

 for perhaps years after birth. Pott (1895) found of 30,000 chil- 

 dren from clinics 95 had heart disease and of these 27 were 

 under two years old, so might be considered as congenital ; this 

 is but a rude approximation and, as suggested, takes no account 

 of the cases presenting no symptoms at the time of examination, 

 so the number may be greater than this study suggests. Ellis 

 (1905) found that there were 51 cases of all cardiac defects in 

 3,875 autopsies at the Pennsylvania hospital, or 1.16 per cent. ; of 

 this number 42 were patent foramen ovale or persistent patency 

 of the ductus arteriosis. 



The question of sex frequency does not seem to be of much 

 significance; there is, however, a slightly greater preponderance 

 of males afifected, as the following table shows : 



Cases Males 



Gintrac, 1814 44. 63.64% 



Friedeberg, 1844 43 67.44% 



Stolker, 1864 79 54.00% 



Peacock, 1866 no 55-54% 



Theremin, 1895 57 56.14% 



Abbot, 1915 513 55-34% 



The present study agrees with the above tables, the percentage 

 of males being 55.69 per cent. 



