CONGENITAL ANOMALIES OF THE HEART. 333 



This blackness of the blood is not in itself capable of producing cyano- 

 sis (as is shown by a case, related by JSreschet^ in which the color of a 

 left arm was perfectly normal, although it contained none save venous 

 blood, the left subclavian artery springing from the pulmonary artery). 

 It cannot be denied, however, that where venous engorgement exists, 

 the degree of cyanosis depends upon the blackness or redness of the 

 blood. Thin-blooded people never exhibit much cyanosis. In cases 

 of congenital imperfection of the heart, in which the pulmonary artery 

 is undeveloped, the dark color of the blood may be ascribed to the 

 mixture of venous and arterial blood which then takes place. In the 

 converse cases, wherein the arterial part of the blood is thrown into 

 the venous portion, the cause of the darkness of hue cannot be found 

 in the mixture, but is to be attributed rather to the extreme retarda- 

 tion of the current.* 



Induration and stricture at the conus arteriosus of the right heart, 

 and the extensive valvular deformities which affect the pulmonary 

 artery, have an effect quite similar to that of arrested development of 

 the arterial trunks, especially as in these cases, too, the septa remain 

 open. 



The deep-blue color of the skin, particularly that of the face, the 

 lips, cheeks, and the tips of the fingers and toes, is the most con- 

 spicuous symptom of congenital deformity of the heart. The collec- 

 tion of venous blood in certain parts also causes their enlargement, 

 due (as has been ascertained by the careful observation of Foerster) to 

 serous infiltration, moderate thickening, and hypertrophy. The nose 

 becomes bulbous, the bluish lips swollen, and the terminal phalanges 

 of the fingers and toes so much thickened as to look like the knobs 

 of drumsticks. The nails are wide and arched. 



Most patients have puny frames with long limbs, and show great 

 tendency to profuse haemorrhage. They are susceptible to cold ; are 

 sluggish, languid, and irritable. They often have imperfect develop- 

 ment of the genitals and feeble sexual power. They suffer attacks of 

 palpitation, oppression, and syncope, and rarely attain the age of 

 forty or fifty years. They nearly always die early of intercurrent dis- 

 ease, which they are ill able to resist, or else they perish from oedema 

 of the lung, dropsy, etc. 



It is remarkable that sometimes the cyanosis and functional dis- 

 turbance just described do not manifest themselves until the period of 



* That the great cyanosis of persons with congenital malformation of the heart is 

 due to an especial cause, becomes evident from the fact that individuals with congeni- 

 tal cyanosis do not become dropsical nearly so soon as those suffering from acquired 

 cyanosis. This would not be the case if the cyanosis were due to venous engorge- 

 ment alone. 



