HYPERTROPHY OF THE HEART. 315 



5. Hypertrophy accompanies general plethora. It is easy to com- 

 prehend that, if the vascular system at large be overfilled, the obsta- 

 cles which the heart has to overcome must be increased. It may, how- 

 ever, very properly be questioned, whether a permanent and general 

 increase of the contents of the vascular system be possible. Such a 

 condition would immediately be compensated for by augmented secre- 

 tion, especially from the kidneys, as urine always continues to form as 

 long as lateral pressure upon the renal arteries and vascular tufts of 

 Malpighi is kept up. 



A transient plethora, however, undoubtedly arises both after every 

 hearty meal and after copious drinking. Persons who, by immoderate 

 eating and drinking, often bring upon themselves this merely transitory 

 plethora, persons who lead a gluttonous life (for example, travelling 

 wine-sellers, who often eat and drink all day long), furnish no incon- 

 siderable contingent to the general mass of cardiac hypertrophy. 



In all cases, mentioned hitherto, it has been more or less distinctly 

 demonstrable that the augmented action of the heart, which gives rise 

 to hypertrophy, proceeds from increased resistance and from the re- 

 quirements of the general organism for such increase of action. To 

 this class of cases another must be added, in which hypertrophy is a 

 result of increased cardiac action without increased resistance. The 

 action of the heart is accelerated by excitement of the passions. In 

 many persons we are forced to assume the existence of an exalted 

 irritability, an erythism of the nervous system, particularly of the 

 nerves of the heart, so that trifling causes serve to excite and 

 strengthen its action. The use of strong coffee, tea, and spirits, has 

 a similar effect, thus furnishing a fresh exciting cause to the class of hy- 

 pertrophies treated of under our fifth heading. Such agencies, however, 

 are far less productive of hypertrophy than those previously mentioned. 



Finally, it must be admitted that we are ignorant of the pathogeny 

 of quite a large number of cases of hypertrophy of the heart, and (in 

 accordance with the objections of Bamberger to the views of Traube) 

 we must reckon among these the hypertrophies which so often com- 

 plicate Brightfs disease without the coexistence of any valvular lesion, 

 or other structural changes in the heart or blood-vessels. 



We sometimes notice that cardiac hypertrophy confines itself to 

 one side of the heart, or even to one ventricle or auricle. It can 

 nearly always be shown that the cavity, whose walls are hyper 

 trophied, has an unusual task to perform. It is more common, how- 

 ever, even though but one orifice be contracted, for the hypertrophy to 

 extend more or less over the entire heart. The former condition is 

 probably the more difficult of explanation, when we reflect that part 

 of the muscular fibres of one ventricle pass over to the other. 



